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.infobox-subbox{padding:0;border:none;margin:-3px;width:auto;min-width:100%;font-size:100%;clear:none;float:none;background-color:transparent}.mw-parser-output .infobox-3cols-child{margin:auto}.mw-parser-output .infobox .navbar{font-size:100%}@media screen{html.skin-theme-clientpref-night .mw-parser-output .infobox-full-data:not(.notheme)>div:not(.notheme)[style]{background:#1f1f23!important;color:#f8f9fa}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .infobox-full-data:not(.notheme) div:not(.notheme){background:#1f1f23!important;color:#f8f9fa}}@media(min-width:640px){body.skin--responsive .mw-parser-output .infobox-table{display:table!important}body.skin--responsive .mw-parser-output .infobox-table>caption{display:table-caption!important}body.skin--responsive .mw-parser-output .infobox-table>tbody{display:table-row-group}body.skin--responsive .mw-parser-output .infobox-table tr{display:table-row!important}body.skin--responsive .mw-parser-output .infobox-table th,body.skin--responsive .mw-parser-output .infobox-table td{padding-left:inherit;padding-right:inherit}}</style><table class="infobox vevent"><caption class="infobox-title summary">bcache</caption><tbody><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Programmer" title="Programmer">Developer(s)</a></th><td class="infobox-data">Kent Overstreet and others</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">June 30, 2013<span class="noprint">; 11 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">2013-06-30</span>)</span> (Linux 3.10)</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Repository_(version_control)" title="Repository (version control)">Repository</a></th><td class="infobox-data"><style data-mw-deduplicate="TemplateStyles:r1126788409">.mw-parser-output .plainlist ol,.mw-parser-output .plainlist ul{line-height:inherit;list-style:none;margin:0;padding:0}.mw-parser-output .plainlist ol li,.mw-parser-output .plainlist ul li{margin-bottom:0}</style><div class="plainlist"><ul><li><span class="url"><a rel="nofollow" class="external text" href="http://evilpiepirate.org/git/linux-bcache.git">evilpiepirate<wbr />.org<wbr />/git<wbr />/linux-bcache<wbr />.git</a></span> <span class="mw-valign-text-top noprint" typeof="mw:File/Frameless"><a href="https://www.wikidata.org/wiki/Q16991599#P1324" title="Edit this at Wikidata"><img alt="Edit this at Wikidata" src="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/10px-OOjs_UI_icon_edit-ltr-progressive.svg.png" decoding="async" width="10" height="10" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/15px-OOjs_UI_icon_edit-ltr-progressive.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/8/8a/OOjs_UI_icon_edit-ltr-progressive.svg/20px-OOjs_UI_icon_edit-ltr-progressive.svg.png 2x" data-file-width="20" data-file-height="20" /></a></span></li></ul> </div></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Written in</th><td class="infobox-data"><a href="/wiki/C_(programming_language)" title="C (programming language)">C</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Operating_system" title="Operating system">Operating system</a></th><td class="infobox-data"><a href="/wiki/Linux" title="Linux">Linux</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_categories#Categorization_approaches" title="Software categories">Type</a></th><td class="infobox-data"><a href="/wiki/Category:Linux_kernel_features" title="Category:Linux kernel features">Linux kernel features</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;"><a href="/wiki/Software_license" title="Software license">License</a></th><td class="infobox-data"><a href="/wiki/GNU_GPL" class="mw-redirect" title="GNU GPL">GNU GPL</a></td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Website</th><td class="infobox-data"><span class="url"><a rel="nofollow" class="external text" href="http://bcache.evilpiepirate.org/">bcache<wbr />.evilpiepirate<wbr />.org</a></span></td></tr></tbody></table> <p><b>bcache</b> (abbreviated from <i>block cache</i>) is a <a href="/wiki/Cache_(computing)" title="Cache (computing)">cache</a> mechanism in the <a href="/wiki/Linux_kernel" title="Linux kernel">Linux kernel</a>'s block layer, which is used for accessing <a href="/wiki/Secondary_storage" class="mw-redirect" title="Secondary storage">secondary storage</a> devices. It allows one or more fast storage devices, such as flash-based <a href="/wiki/Solid-state_drive" title="Solid-state drive">solid-state drives</a> (SSDs), to act as a cache for one or more slower storage devices, such as <a href="/wiki/Hard_disk_drive" title="Hard disk drive">hard disk drives</a> (HDDs); this effectively creates <a href="/wiki/Hybrid_volume" class="mw-redirect" title="Hybrid volume">hybrid volumes</a> and provides performance improvements. </p><p>Designed around the nature and performance characteristics of SSDs, bcache also minimizes <a href="/wiki/Write_amplification" title="Write amplification">write amplification</a> by avoiding <a href="/wiki/Random_write" class="mw-redirect" title="Random write">random writes</a> and turning them into <a href="/wiki/Sequential_write" class="mw-redirect" title="Sequential write">sequential writes</a> instead. This merging of <a href="/wiki/I/O_operation" class="mw-redirect" title="I/O operation">I/O operations</a> is performed for both the cache and the primary storage, helping in extending the lifetime of flash-based devices used as caches, and in improving the performance of write-sensitive primary storages, such as <a href="/wiki/RAID_5" class="mw-redirect" title="RAID 5">RAID 5</a> sets. </p><p>bcache is licensed under the <a href="/wiki/GNU_General_Public_License" title="GNU General Public License">GNU General Public License</a> (GPL), and Kent Overstreet is its primary developer. Overstreet considers bcache as a "prototype" for the development of <a href="/wiki/Bcachefs" title="Bcachefs">bcachefs</a>, a filesystem with significant improvements over bcache.<sup id="cite_ref-1" class="reference"><a href="#cite_note-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Overview">Overview</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=1" title="Edit section: Overview"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Using bcache makes it possible to have SSDs as another level of indirection within the data storage access paths, resulting in improved overall performance by using fast <a href="/wiki/Flash_memory" title="Flash memory">flash</a>-based SSDs as caches for slower mechanical hard disk drives (HDDs) with rotational <a href="/wiki/Magnetic_storage" title="Magnetic storage">magnetic media</a>. That way, the gap between SSDs and HDDs can be bridged –  the costly speed of SSDs gets combined with the cheap storage capacity of traditional HDDs.<sup id="cite_ref-2" class="reference"><a href="#cite_note-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup> </p><p>Caching is implemented by using SSDs for storing data associated with performed <a href="/wiki/Random_read" class="mw-redirect" title="Random read">random reads</a> and random writes, using near-zero <a href="/wiki/Seek_time" class="mw-redirect" title="Seek time">seek times</a> as the most prominent feature of SSDs. <a href="/wiki/Sequential_I/O" class="mw-redirect" title="Sequential I/O">Sequential I/O</a> is not cached, to avoid rapid SSD <a href="/wiki/Cache_invalidation" title="Cache invalidation">cache invalidation</a> on such operations that are already suitable enough for HDDs; going around the cache for big sequential writes is known as the <a href="/wiki/Write-around" class="mw-redirect" title="Write-around">write-around</a> policy. Not caching the sequential <a href="/wiki/Input/output" title="Input/output">I/O</a> also helps in extending the lifetime of SSDs used as caches.<sup id="cite_ref-kernel-docs_3-0" class="reference"><a href="#cite_note-kernel-docs-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> <a href="/wiki/Write_amplification" title="Write amplification">Write amplification</a> is avoided by not performing random writes to SSDs; instead, all random writes to SSD caches are always combined into block-level writes, ending up with rewriting only the complete <a href="/wiki/Erase_block" class="mw-redirect" title="Erase block">erase blocks</a> on SSDs.<sup id="cite_ref-bcache_4-0" class="reference"><a href="#cite_note-bcache-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-lwn-497024_5-0" class="reference"><a href="#cite_note-lwn-497024-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Both <i><a href="/wiki/Write-back" class="mw-redirect" title="Write-back">write-back</a></i> and <i><a href="/wiki/Write-through" class="mw-redirect" title="Write-through">write-through</a></i> (which is the default) policies are supported for caching write operations. In case of the write-back policy, written data is stored inside the SSD caches first, and propagated to the HDDs later in a batched way while performing seek-friendly operations –  making bcache to act also as an <a href="/wiki/I/O_scheduler" class="mw-redirect" title="I/O scheduler">I/O scheduler</a>. For the write-through policy, which ensures that no write operation is marked as finished until the data requested to be written has reached both SSDs and HDDs, performance improvements are reduced by effectively performing only caching of the written data.<sup id="cite_ref-bcache_4-1" class="reference"><a href="#cite_note-bcache-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-lwn-497024_5-1" class="reference"><a href="#cite_note-lwn-497024-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Write-back policy with batched writes to HDDs provides additional benefits to write-sensitive <a href="/wiki/Redundant_array_of_independent_disks" class="mw-redirect" title="Redundant array of independent disks">redundant array of independent disks</a> (RAID) layouts such as <a href="/wiki/RAID_5" class="mw-redirect" title="RAID 5">RAID 5</a> and <a href="/wiki/RAID_6" class="mw-redirect" title="RAID 6">RAID 6</a>, which perform actual write operations as <a href="/wiki/Atomic_operation" class="mw-redirect" title="Atomic operation">atomic</a> <a href="/wiki/Read-modify-write" class="mw-redirect" title="Read-modify-write">read-modify-write</a> sequences. That way, performance penalties<sup id="cite_ref-6" class="reference"><a href="#cite_note-6"><span class="cite-bracket">[</span>6<span class="cite-bracket">]</span></a></sup> of small random writes are reduced or avoided for such RAID layouts, by grouping them together and performing as batched sequential writes.<sup id="cite_ref-bcache_4-2" class="reference"><a href="#cite_note-bcache-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-lwn-497024_5-2" class="reference"><a href="#cite_note-lwn-497024-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>Caching performed by bcache operates at the <a href="/wiki/Block_device" class="mw-redirect" title="Block device">block device</a> level, making itself <a href="/wiki/File_system" title="File system">file system</a>–agnostic as long as the file system provides an embedded <a href="/wiki/Universally_unique_identifier" title="Universally unique identifier">universally unique identifier</a> (UUID); this requirement is satisfied by virtually all standard <a href="/wiki/Linux_file_systems" class="mw-redirect" title="Linux file systems">Linux file systems</a>, as well as by <a href="/wiki/Linux_swap" class="mw-redirect" title="Linux swap">swap partitions</a>. Sizes of the logical blocks used internally by bcache as caching extents can go down to the size of a single HDD sector.<sup id="cite_ref-7" class="reference"><a href="#cite_note-7"><span class="cite-bracket">[</span>7<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="History">History</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=2" title="Edit section: History"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>bcache was first announced by Kent Overstreet in July 2010, as a completely working Linux kernel module, though at its early beta stage.<sup id="cite_ref-8" class="reference"><a href="#cite_note-8"><span class="cite-bracket">[</span>8<span class="cite-bracket">]</span></a></sup> The development continued for almost two years, until May 2012, at which point bcache reached its production-ready state.<sup id="cite_ref-lwn-497024_5-3" class="reference"><a href="#cite_note-lwn-497024-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup> </p><p>It was merged into the <a href="/wiki/Linux_kernel_mainline" class="mw-redirect" title="Linux kernel mainline">Linux kernel mainline</a> in kernel version 3.10, released on June 30, 2013.<sup id="cite_ref-9" class="reference"><a href="#cite_note-9"><span class="cite-bracket">[</span>9<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-bcache-kent_10-0" class="reference"><a href="#cite_note-bcache-kent-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> Overstreet has since been developing the <a href="/wiki/File_system" title="File system">file system</a> <a href="/wiki/Bcachefs" title="Bcachefs">bcachefs</a>, based on ideas first developed in bcache that he said began "evolving ... into a full blown, general-purpose <a href="/wiki/POSIX" title="POSIX">POSIX</a> filesystem".<sup id="cite_ref-11" class="reference"><a href="#cite_note-11"><span class="cite-bracket">[</span>11<span class="cite-bracket">]</span></a></sup> He describes bcache as a "prototype" for the ideas that became bcachefs and intends bcachefs to replace bcache.<sup id="cite_ref-12" class="reference"><a href="#cite_note-12"><span class="cite-bracket">[</span>12<span class="cite-bracket">]</span></a></sup> He officially announced bcachefs in 2015 and got it merged into the mainline Linux kernel in October 2023.<sup id="cite_ref-13" class="reference"><a href="#cite_note-13"><span class="cite-bracket">[</span>13<span class="cite-bracket">]</span></a></sup> </p> <div class="mw-heading mw-heading2"><h2 id="Features">Features</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=3" title="Edit section: Features"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As of version 3.10 of the Linux kernel, the following features are provided by bcache:<sup id="cite_ref-bcache_4-3" class="reference"><a href="#cite_note-bcache-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup> </p> <ul><li>The same cache device can be used for caching an arbitrary number of the primary storage devices</li> <li>Runtime attaching and detaching of primary storage devices from their caches, while mounted and in use (running in passthrough mode when not cached)</li> <li>Automated recovery from unclean shutdowns –  writes are not completed until the cache is consistent with respect to the primary storage device; internally, bcache makes no distinction between clean and unclean shutdowns</li> <li>Transparent handling of I/O errors generated by the cache devices<sup id="cite_ref-kernel-docs_3-1" class="reference"><a href="#cite_note-kernel-docs-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></li> <li><a href="/wiki/Write_barrier" title="Write barrier">Write barriers</a> and associated cache flushes are properly handled</li> <li>Write-through (which is the default), write-back and write-around policies</li> <li>Sequential I/O is detected and bypassed, with configurable thresholds; bypassing can also be disabled</li> <li>Throttling of the I/O to the SSD if it becomes congested, as detected by measured latency of the SSD's I/O operations exceeding a configurable threshold; useful for configurations having one SSD providing caching for many HDDs</li> <li><a href="/wiki/Readahead" title="Readahead">Readahead</a> on a <a href="/wiki/Cache_miss" class="mw-redirect" title="Cache miss">cache miss</a> (disabled by default)</li> <li>Highly efficient write-back implementation –  dirty data is always written out in sorted order, and optionally background write-back is smoothly throttled down to keeping configured percentage of the cache dirty</li> <li>High-performance <a href="/wiki/B%2B_tree" title="B+ tree">B+ trees</a> are used internally –  bcache is capable of around 1,000,000 <a href="/wiki/IOPS" title="IOPS">IOPS</a> on random reads, if the hardware is fast enough</li> <li>Various runtime statistics and configuration options are exposed through <a href="/wiki/Sysfs" title="Sysfs">sysfs</a><sup id="cite_ref-kernel-docs_3-2" class="reference"><a href="#cite_note-kernel-docs-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup></li></ul> <div class="mw-heading mw-heading3"><h3 id="Improvements">Improvements</h3><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=4" title="Edit section: Improvements"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>As of February 2014<sup class="plainlinks noexcerpt noprint asof-tag update" style="display:none;"><a class="external text" href="https://en.wikipedia.org/w/index.php?title=Bcache&action=edit">[update]</a></sup>, the following new features are planned for the future releases of bcache:<sup id="cite_ref-bcache-kent_10-1" class="reference"><a href="#cite_note-bcache-kent-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p> <ul><li>Awareness of <a href="/wiki/Data_striping" title="Data striping">data striping</a> in RAID 5 and RAID 6 layouts –  adding awareness of the stripe layout to the write-back policy, so decisions on caching will be giving preference to already "dirty" stripes, and actual background flushes will be writing out complete stripes first</li> <li>Handling cache misses with already full B+ tree nodes –  as of the bcache version in Linux kernel 3.10, splits of the internally used B+ tree nodes happen on writes, making initial cache warm-ups hardly achievable</li> <li>Multiple SSDs in a cache set –  only dirty data (for the write-back policy) and <a href="/wiki/Metadata" title="Metadata">metadata</a> would be mirrored, without wasting SSD space for the clean data and read caches</li> <li>Data <a href="/wiki/Checksum" title="Checksum">checksumming</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="See_also">See also</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=5" title="Edit section: See also"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1266661725">.mw-parser-output .portalbox{padding:0;margin:0.5em 0;display:table;box-sizing:border-box;max-width:175px;list-style:none}.mw-parser-output .portalborder{border:1px solid var(--border-color-base,#a2a9b1);padding:0.1em;background:var(--background-color-neutral-subtle,#f8f9fa)}.mw-parser-output .portalbox-entry{display:table-row;font-size:85%;line-height:110%;height:1.9em;font-style:italic;font-weight:bold}.mw-parser-output .portalbox-image{display:table-cell;padding:0.2em;vertical-align:middle;text-align:center}.mw-parser-output .portalbox-link{display:table-cell;padding:0.2em 0.2em 0.2em 0.3em;vertical-align:middle}@media(min-width:720px){.mw-parser-output .portalleft{margin:0.5em 1em 0.5em 0}.mw-parser-output .portalright{clear:right;float:right;margin:0.5em 0 0.5em 1em}}</style><ul role="navigation" aria-label="Portals" class="noprint portalbox portalborder portalright"> <li class="portalbox-entry"><span class="portalbox-image"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/28px-Free_and_open-source_software_logo_%282009%29.svg.png" decoding="async" width="28" height="28" class="mw-file-element" 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srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/35px-NewTux.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/47px-NewTux.svg.png 2x" data-file-width="625" data-file-height="750" /></a></span></span><span class="portalbox-link"><a href="/wiki/Portal:Linux" title="Portal:Linux">Linux portal</a></span></li></ul> <ul><li><a href="/wiki/Dm-cache" title="Dm-cache">dm-cache</a> –  a Linux kernel's device mapper target that allows creation of hybrid volumes</li> <li><a href="/wiki/EnhanceIO" title="EnhanceIO">EnhanceIO</a> –  a disk cache module for the Linux kernel.</li> <li><a href="/wiki/Flashcache" title="Flashcache">Flashcache</a> –  a disk cache component for the Linux kernel, initially developed by Facebook</li> <li><a href="/wiki/Hybrid_drive" title="Hybrid drive">Hybrid drive</a> –  a storage device that combines flash-based and spinning magnetic media storage technologies</li> <li><a href="/wiki/ReadyBoost" title="ReadyBoost">ReadyBoost</a> –  a disk caching software component of Windows Vista and later Microsoft operating systems</li> <li><a href="/wiki/Smart_Response_Technology" title="Smart Response Technology">Smart Response Technology</a> (SRT) –  a proprietary disk storage caching mechanism, developed by Intel for its chipsets</li></ul> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=6" title="Edit section: References"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <style data-mw-deduplicate="TemplateStyles:r1239543626">.mw-parser-output .reflist{margin-bottom:0.5em;list-style-type:decimal}@media screen{.mw-parser-output .reflist{font-size:90%}}.mw-parser-output .reflist .references{font-size:100%;margin-bottom:0;list-style-type:inherit}.mw-parser-output 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cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://bcache.evilpiepirate.org/FAQ/">"bcache FAQ"</a>. <i>bcache.evilpiepirate.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">May 7,</span> 2021</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=bcache.evilpiepirate.org&rft.atitle=bcache+FAQ&rft_id=https%3A%2F%2Fbcache.evilpiepirate.org%2FFAQ%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-2"><span class="mw-cite-backlink"><b><a href="#cite_ref-2">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFPetros_Koutoupis2013" class="citation web cs1">Petros Koutoupis (November 25, 2013). <a rel="nofollow" class="external text" href="http://www.linuxjournal.com/content/advanced-hard-drive-caching-techniques">"Advanced Hard Drive Caching Techniques"</a>. <a href="/wiki/Linux_Journal" title="Linux Journal">Linux Journal</a><span class="reference-accessdate">. Retrieved <span class="nowrap">December 2,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Advanced+Hard+Drive+Caching+Techniques&rft.pub=Linux+Journal&rft.date=2013-11-25&rft.au=Petros+Koutoupis&rft_id=http%3A%2F%2Fwww.linuxjournal.com%2Fcontent%2Fadvanced-hard-drive-caching-techniques&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-kernel-docs-3"><span class="mw-cite-backlink">^ <a href="#cite_ref-kernel-docs_3-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-kernel-docs_3-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-kernel-docs_3-2"><sup><i><b>c</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://www.kernel.org/doc/Documentation/bcache.txt">"Linux kernel documentation: Documentation/bcache.txt"</a>. <a href="/wiki/Kernel.org" title="Kernel.org">kernel.org</a>. August 12, 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">January 24,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=Linux+kernel+documentation%3A+Documentation%2Fbcache.txt&rft.pub=kernel.org&rft.date=2013-08-12&rft_id=https%3A%2F%2Fwww.kernel.org%2Fdoc%2FDocumentation%2Fbcache.txt&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-bcache-4"><span class="mw-cite-backlink">^ <a href="#cite_ref-bcache_4-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-bcache_4-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-bcache_4-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-bcache_4-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKent_Overstreet" class="citation web cs1">Kent Overstreet. <a rel="nofollow" class="external text" href="http://bcache.evilpiepirate.org/">"bcache: Linux kernel block layer cache"</a>. <i>bcache.evilpiepirate.org</i><span class="reference-accessdate">. Retrieved <span class="nowrap">December 2,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=bcache.evilpiepirate.org&rft.atitle=bcache%3A+Linux+kernel+block+layer+cache&rft.au=Kent+Overstreet&rft_id=http%3A%2F%2Fbcache.evilpiepirate.org%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-lwn-497024-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-lwn-497024_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-lwn-497024_5-1"><sup><i><b>b</b></i></sup></a> <a href="#cite_ref-lwn-497024_5-2"><sup><i><b>c</b></i></sup></a> <a href="#cite_ref-lwn-497024_5-3"><sup><i><b>d</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFJonathan_Corbet2012" class="citation web cs1">Jonathan Corbet (May 12, 2012). <a rel="nofollow" class="external text" href="https://lwn.net/Articles/497024/">"A bcache update"</a>. <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a><span class="reference-accessdate">. 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Retrieved <span class="nowrap">October 4,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=ecs.umass.edu&rft.atitle=Basic+RAID+Organizations&rft_id=http%3A%2F%2Fwww.ecs.umass.edu%2Fece%2Fkoren%2Farchitecture%2FRaid%2FbasicRAID.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-7"><span class="mw-cite-backlink"><b><a href="#cite_ref-7">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFWilliam_StearnsKent_Overstreet2010" class="citation web cs1">William Stearns; Kent Overstreet (July 2, 2010). <a rel="nofollow" class="external text" href="https://lwn.net/Articles/394672/">"bcache: Caching beyond just RAM"</a>. <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a><span class="reference-accessdate">. Retrieved <span class="nowrap">October 4,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=bcache%3A+Caching+beyond+just+RAM&rft.pub=LWN.net&rft.date=2010-07-02&rft.au=William+Stearns&rft.au=Kent+Overstreet&rft_id=https%3A%2F%2Flwn.net%2FArticles%2F394672%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-8"><span class="mw-cite-backlink"><b><a href="#cite_ref-8">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFKent_Overstreet2010" class="citation web cs1">Kent Overstreet (July 4, 2010). <a rel="nofollow" class="external text" href="https://lwn.net/Articles/394905/">"bcache: Version 6"</a>. <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a><span class="reference-accessdate">. Retrieved <span class="nowrap">October 4,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=bcache%3A+Version+6&rft.pub=LWN.net&rft.date=2010-07-04&rft.au=Kent+Overstreet&rft_id=https%3A%2F%2Flwn.net%2FArticles%2F394905%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-9"><span class="mw-cite-backlink"><b><a href="#cite_ref-9">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite class="citation web cs1"><a rel="nofollow" class="external text" href="https://kernelnewbies.org/Linux_3.10#Bcache.2C_a_block_layer_cache_for_SSD_caching">"Linux kernel 3.10, Section 1.2. bcache, a block layer cache for SSD caching"</a>. <i>kernelnewbies.org</i>. June 30, 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">October 4,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=kernelnewbies.org&rft.atitle=Linux+kernel+3.10%2C+Section+1.2.+bcache%2C+a+block+layer+cache+for+SSD+caching&rft.date=2013-06-30&rft_id=https%3A%2F%2Fkernelnewbies.org%2FLinux_3.10%23Bcache.2C_a_block_layer_cache_for_SSD_caching&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-bcache-kent-10"><span class="mw-cite-backlink">^ <a href="#cite_ref-bcache-kent_10-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-bcache-kent_10-1"><sup><i><b>b</b></i></sup></a></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLibby_Clark2013" class="citation web cs1">Libby Clark (June 11, 2013). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130929230638/http://www.linux.com/news/featured-blogs/200-libby-clark/728209-about-the-linux-kernel-bcache/">"All About the Linux Kernel: bcache"</a>. <i>linux.com</i>. Archived from <a rel="nofollow" class="external text" href="http://www.linux.com/news/featured-blogs/200-libby-clark/728209-about-the-linux-kernel-bcache">the original</a> on September 29, 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">October 9,</span> 2013</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=linux.com&rft.atitle=All+About+the+Linux+Kernel%3A+bcache&rft.date=2013-06-11&rft.au=Libby+Clark&rft_id=http%3A%2F%2Fwww.linux.com%2Fnews%2Ffeatured-blogs%2F200-libby-clark%2F728209-about-the-linux-kernel-bcache&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-11"><span class="mw-cite-backlink"><b><a href="#cite_ref-11">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLarabel2015" class="citation web cs1">Larabel, Michael (August 21, 2015). <a rel="nofollow" class="external text" href="https://www.phoronix.com/scan.php?page=article&item=bcache-fs-linux&num=1">"A New Linux File-System Aims For Speed While Having ZFS/Btrfs-Like Features"</a>. <i><a href="/wiki/Phoronix" class="mw-redirect" title="Phoronix">Phoronix</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">November 22,</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Phoronix&rft.atitle=A+New+Linux+File-System+Aims+For+Speed+While+Having+ZFS%2FBtrfs-Like+Features&rft.date=2015-08-21&rft.aulast=Larabel&rft.aufirst=Michael&rft_id=https%3A%2F%2Fwww.phoronix.com%2Fscan.php%3Fpage%3Darticle%26item%3Dbcache-fs-linux%26num%3D1&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-12"><span class="mw-cite-backlink"><b><a href="#cite_ref-12">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFEdge2018" class="citation web cs1">Edge, Jake (May 23, 2018). <a rel="nofollow" class="external text" href="https://lwn.net/Articles/755276/">"An update on bcachefs"</a>. <i><a href="/wiki/LWN.net" title="LWN.net">LWN.net</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">November 22,</span> 2018</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=LWN.net&rft.atitle=An+update+on+bcachefs&rft.date=2018-05-23&rft.aulast=Edge&rft.aufirst=Jake&rft_id=https%3A%2F%2Flwn.net%2FArticles%2F755276%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> <li id="cite_note-13"><span class="mw-cite-backlink"><b><a href="#cite_ref-13">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222"><cite id="CITEREFLarabel2023" class="citation web cs1">Larabel, Michael (October 31, 2023). <a rel="nofollow" class="external text" href="https://www.phoronix.com/news/Bcachefs-Merged-Linux-6.7">"Bcachefs Merged Into The Linux 6.7 Kernel"</a>. <i><a href="/wiki/Phoronix" class="mw-redirect" title="Phoronix">Phoronix</a></i><span class="reference-accessdate">. Retrieved <span class="nowrap">November 20,</span> 2023</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=Phoronix&rft.atitle=Bcachefs+Merged+Into+The+Linux+6.7+Kernel&rft.date=2023-10-31&rft.aulast=Larabel&rft.aufirst=Michael&rft_id=https%3A%2F%2Fwww.phoronix.com%2Fnews%2FBcachefs-Merged-Linux-6.7&rfr_id=info%3Asid%2Fen.wikipedia.org%3ABcache" class="Z3988"></span></span> </li> </ol></div> <div class="mw-heading mw-heading2"><h2 id="External_links">External links</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Bcache&action=edit&section=7" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><span class="official-website"><span class="url"><a rel="nofollow" class="external text" href="http://bcache.evilpiepirate.org/">Official website</a></span></span></li> <li><a rel="nofollow" class="external text" href="https://lwn.net/Articles/548348/">LSFMM: Caching –  dm-cache and bcache</a>, <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a>, May 1, 2013, by Jake Edge</li> <li><a rel="nofollow" class="external text" href="http://en.community.dell.com/techcenter/extras/m/white_papers/20438199/download">Linux Block Caching Choices in Stable Upstream Kernel</a> (PDF), <a href="/wiki/Dell" title="Dell">Dell</a>, December 2013</li> <li>Testing bcache series: <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100829082801/http://www.linux-mag.com/id/7843/">Throughput</a><sup><a href="/wiki/Template:Usurped/doc" title="Template:Usurped/doc">[usurped]</a></sup>, <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100911085025/http://www.linux-mag.com/id/7847">IOPS</a><sup><a href="/wiki/Template:Usurped/doc" title="Template:Usurped/doc">[usurped]</a></sup>, <a rel="nofollow" class="external text" href="https://web.archive.org/web/20100920062520/http://www.linux-mag.com/id/7852">Metadata</a><sup><a href="/wiki/Template:Usurped/doc" title="Template:Usurped/doc">[usurped]</a></sup>, and <a rel="nofollow" class="external text" href="https://web.archive.org/web/20101002103446/http://www.linux-mag.com/id/7858">Large Files and a Wrap-Up</a><sup><a href="/wiki/Template:Usurped/doc" title="Template:Usurped/doc">[usurped]</a></sup>, <i><a href="/wiki/Linux_Magazine" title="Linux Magazine">Linux Magazine</a></i>, August–September 2010, by Jeffrey B. Layton</li> <li><a rel="nofollow" class="external text" href="http://lkml.indiana.edu/hypermail/linux/kernel/1306.1/01246.html">Performance Comparison among EnhanceIO, bcache and dm-cache</a>, <a href="/wiki/LKML" class="mw-redirect" title="LKML">LKML</a>, June 11, 2013</li> <li><a rel="nofollow" class="external text" href="https://www.phoronix.com/scan.php?page=news_item&px=MTM4ODA">EnhanceIO, Bcache & DM-Cache Benchmarked</a>, <a href="/wiki/Phoronix" class="mw-redirect" title="Phoronix">Phoronix</a>, June 11, 2013, by Michael Larabel</li></ul> <div style="clear:both;" class=""></div> <div class="navbox-styles"><style data-mw-deduplicate="TemplateStyles:r1129693374">.mw-parser-output .hlist dl,.mw-parser-output .hlist ol,.mw-parser-output .hlist ul{margin:0;padding:0}.mw-parser-output .hlist dd,.mw-parser-output .hlist dt,.mw-parser-output .hlist li{margin:0;display:inline}.mw-parser-output .hlist.inline,.mw-parser-output .hlist.inline dl,.mw-parser-output .hlist.inline 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computer architectures</a></li> <li><a href="/wiki/Linux_kernel_version_history" title="Linux kernel version history">Version history</a></li> <li><a href="/wiki/Criticism_of_Linux" title="Criticism of Linux">Criticism</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Support</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>Developers <ul><li><i><a href="/wiki/The_Linux_Programming_Interface" title="The Linux Programming Interface">The Linux Programming Interface</a></i></li> <li><a href="/wiki/Kernel.org" title="Kernel.org">kernel.org</a></li> <li><a href="/wiki/Linux_kernel_mailing_list" title="Linux kernel mailing list">LKML</a></li> <li><a href="/wiki/Linux_conference" class="mw-redirect" title="Linux conference">Linux conferences</a></li></ul></li> <li>Users <ul><li><a href="/wiki/Linux_user_group" title="Linux user group">Linux User Group (LUG)</a></li></ul></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Technical</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Debugging</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CRIU" title="CRIU">CRIU</a></li> <li><a href="/wiki/Ftrace" title="Ftrace">ftrace</a></li> <li><a href="/wiki/Kdump_(Linux)" title="Kdump (Linux)">kdump</a></li> <li><a href="/wiki/Linux_kernel_oops" title="Linux kernel oops">Linux kernel oops</a></li> <li><a href="/wiki/SystemTap" title="SystemTap">SystemTap</a></li> <li><a href="/wiki/Berkeley_Packet_Filter" title="Berkeley Packet Filter">BPF</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Booting_process_of_Linux" title="Booting process of Linux">Startup</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Vmlinux" title="Vmlinux">vmlinux</a></li> <li><a href="/wiki/System.map" title="System.map">System.map</a></li> <li><a href="/wiki/Dracut_(software)" title="Dracut (software)">dracut</a></li> <li><a href="/wiki/Initrd" class="mw-redirect" title="Initrd">initrd</a></li> <li><a href="/wiki/Initramfs" class="mw-redirect" title="Initramfs">initramfs</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_kernel_interfaces" title="Linux kernel interfaces">ABIs</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Linux_Standard_Base" title="Linux Standard Base">Linux Standard Base</a></li> <li><a href="/wiki/X32_ABI" title="X32 ABI">x32 ABI</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_kernel_interfaces" title="Linux kernel interfaces">APIs</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%">Kernel</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_kernel_interfaces#SCI" title="Linux kernel interfaces">System Call<br />Interface</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/POSIX" title="POSIX">POSIX</a> <ul><li><a href="/wiki/Ioctl" title="Ioctl">ioctl</a></li> <li><a href="/wiki/Select_(Unix)" title="Select (Unix)">select</a></li> <li><a href="/wiki/Open_(system_call)" title="Open (system call)">open</a></li> <li><a href="/wiki/Read_(system_call)" title="Read (system call)">read</a></li> <li><a href="/wiki/Close_(system_call)" title="Close (system call)">close</a></li> <li><a href="/wiki/Sync_(Unix)" title="Sync (Unix)">sync</a></li> <li>…</li></ul></li> <li><a href="/wiki/Linux_kernel_interfaces#Additions_to_POSIX" title="Linux kernel interfaces">Linux-only</a> <ul><li><a href="/wiki/Futex" title="Futex">futex</a></li> <li><a href="/wiki/Epoll" title="Epoll">epoll</a></li> <li><a href="/wiki/Splice_(system_call)" title="Splice (system call)">splice</a></li> <li><a href="/wiki/Dnotify" title="Dnotify">dnotify</a></li> <li><a href="/wiki/Inotify" title="Inotify">inotify</a></li> <li><a href="/wiki/Readahead" title="Readahead">readahead</a></li> <li>…</li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_kernel_interfaces#In–kernel_APIs" title="Linux kernel interfaces">In-kernel</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Advanced_Linux_Sound_Architecture" title="Advanced Linux Sound Architecture">ALSA</a></li> <li><a href="/wiki/Crypto_API_(Linux)" title="Crypto API (Linux)">Crypto API</a></li> <li><a href="/wiki/Io_uring" title="Io uring">io uring</a></li> <li><a href="/wiki/Direct_Rendering_Manager" title="Direct Rendering Manager">DRM</a></li> <li><a href="/wiki/Kernfs_(Linux)" title="Kernfs (Linux)">kernfs</a></li> <li><a href="/wiki/Memory_barrier" title="Memory barrier">Memory barrier</a></li> <li><a href="/wiki/New_API" title="New API">New API</a></li> <li><a href="/wiki/Read-copy-update" title="Read-copy-update">RCU</a></li> <li><a href="/wiki/Video4Linux" title="Video4Linux">Video4Linux</a></li> <li><a href="/wiki/IIO_Framework" title="IIO Framework">IIO</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/User_space_and_kernel_space" title="User space and kernel space">Userspace</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Daemon_(computing)" title="Daemon (computing)">Daemons</a>,<br /><a href="/wiki/Virtual_file_system" title="Virtual file system">File systems</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li>bpffs</li> <li><a href="/wiki/Configfs" title="Configfs">configfs</a></li> <li><a href="/wiki/Devfs" class="mw-redirect" title="Devfs">devfs</a></li> <li><a href="/wiki/Devpts" title="Devpts">devpts</a></li> <li><a href="/wiki/Debugfs" title="Debugfs">debugfs</a></li> <li><a href="/wiki/Filesystem_in_Userspace" title="Filesystem in Userspace">FUSE</a></li> <li>hugetlbfs</li> <li>pipefs</li> <li><a href="/wiki/Procfs" title="Procfs">procfs</a></li> <li>securityfs</li> <li>sockfs</li> <li><a href="/wiki/Sysfs" title="Sysfs">sysfs</a></li> <li><a href="/wiki/Tmpfs" title="Tmpfs">tmpfs</a></li> <li><a href="/wiki/Systemd" title="Systemd">systemd</a> <ul><li><a href="/wiki/Udev" title="Udev">udev</a></li></ul></li> <li><a href="/wiki/Kmscon" title="Kmscon">Kmscon</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Wrapper_library" title="Wrapper library">Wrapper<br />libraries</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/C_standard_library" title="C standard library">C standard library</a> <ul><li><a href="/wiki/Glibc" title="Glibc">glibc</a></li> <li><a href="/wiki/UClibc" title="UClibc">uClibc</a></li> <li><a href="/wiki/Bionic_(software)" title="Bionic (software)">Bionic</a> <ul><li><a href="/wiki/Libhybris" title="Libhybris">libhybris</a></li></ul></li> <li><a href="/wiki/Dietlibc" title="Dietlibc">dietlibc</a></li> <li><a href="/wiki/Embedded_GLIBC" class="mw-redirect" title="Embedded GLIBC">EGLIBC</a></li> <li><a href="/wiki/Klibc" title="Klibc">klibc</a></li> <li><a href="/wiki/Musl" title="Musl">musl</a></li> <li><a href="/wiki/Newlib" title="Newlib">Newlib</a></li></ul></li> <li><a href="/wiki/Cgroups" title="Cgroups">libcgroup</a></li> <li><a href="/wiki/Direct_Rendering_Manager" title="Direct Rendering Manager">libdrm</a></li> <li><a href="/wiki/Advanced_Linux_Sound_Architecture" title="Advanced Linux Sound Architecture">libalsa</a></li> <li><a href="/wiki/Evdev" title="Evdev">libevdev</a></li> <li><a href="/wiki/Libusb" title="Libusb">libusb</a></li> <li><a href="/wiki/Io_uring" title="Io uring">liburing</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Components</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Loadable_kernel_module" title="Loadable kernel module">Kernel modules</a></li> <li><a href="/wiki/BlueZ" class="mw-redirect" title="BlueZ">BlueZ</a></li> <li><a href="/wiki/Cgroups" title="Cgroups">cgroups</a></li> <li><a href="/wiki/Linux_console" title="Linux console">Console</a></li> <li><a class="mw-selflink selflink">bcache</a></li> <li><a href="/wiki/Device_mapper" title="Device mapper">Device mapper</a></li> <li><a href="/wiki/Dm-cache" title="Dm-cache">dm-cache</a></li> <li><a href="/wiki/Dm-crypt" title="Dm-crypt">dm-crypt</a></li> <li><a href="/wiki/Direct_Rendering_Manager" title="Direct Rendering Manager">DRM</a></li> <li><a href="/wiki/EDAC_(Linux)" class="mw-redirect" title="EDAC (Linux)">EDAC</a></li> <li><a href="/wiki/Evdev" title="Evdev">evdev</a></li> <li><a href="/wiki/Kernel_same-page_merging" title="Kernel same-page merging">Kernel same-page merging</a> (KSM)</li> <li><a href="/wiki/LIO_(SCSI_target)" title="LIO (SCSI target)">LIO</a></li> <li><a href="/wiki/Linux_framebuffer" title="Linux framebuffer">Framebuffer</a></li> <li><a href="/wiki/Logical_Volume_Manager_(Linux)" title="Logical Volume Manager (Linux)">LVM</a></li> <li><a href="/wiki/KMS_driver" class="mw-redirect" title="KMS driver">KMS driver</a></li> <li><a href="/wiki/Netfilter" title="Netfilter">Netfilter</a></li> <li><a href="/wiki/Netlink" title="Netlink">Netlink</a></li> <li><a href="/wiki/Nftables" title="Nftables">nftables</a></li> <li><a href="/wiki/Network_scheduler" title="Network scheduler">Network scheduler</a></li> <li><a href="/wiki/Perf_(Linux)" title="Perf (Linux)">perf</a></li> <li><a href="/wiki/SLUB_(software)" title="SLUB (software)">SLUB</a></li> <li><a href="/wiki/Zram" title="Zram">zram</a></li> <li><a href="/wiki/Zswap" title="Zswap">zswap</a></li></ul> <ul><li><a href="/wiki/Scheduling_(computing)#Linux" title="Scheduling (computing)">Process and I/O schedulers</a>:</li> <li><a href="/wiki/Brain_Fuck_Scheduler" title="Brain Fuck Scheduler">Brain Fuck Scheduler</a></li> <li><a href="/wiki/Completely_Fair_Scheduler" title="Completely Fair Scheduler">Completely Fair Scheduler</a> (CFS)</li> <li><a href="/wiki/Earliest_eligible_virtual_deadline_first_scheduling" title="Earliest eligible virtual deadline first scheduling">Earliest eligible virtual deadline first</a> (EEVDF)</li> <li><a href="/wiki/Noop_scheduler" title="Noop scheduler">Noop scheduler</a></li> <li><a href="/wiki/O(n)_scheduler" title="O(n) scheduler">O(n) scheduler</a></li> <li><a href="/wiki/O(1)_scheduler" title="O(1) scheduler">O(1) scheduler</a></li> <li><a href="/wiki/SCHED_DEADLINE" title="SCHED DEADLINE">SCHED_DEADLINE</a></li> <li><a href="/wiki/SCHED_FIFO" class="mw-redirect" title="SCHED FIFO">SCHED_FIFO</a></li> <li><a href="/wiki/SCHED_RR" class="mw-redirect" title="SCHED RR">SCHED_RR</a></li></ul> <ul><li><a href="/wiki/Linux_Security_Modules" title="Linux Security Modules">Security Modules</a>: <a href="/wiki/AppArmor" title="AppArmor">AppArmor</a></li> <li><a href="/wiki/Exec_Shield" title="Exec Shield">Exec Shield</a></li> <li><a href="/wiki/Seccomp" title="Seccomp">seccomp</a></li> <li><a href="/wiki/Security-Enhanced_Linux" title="Security-Enhanced Linux">SELinux</a></li> <li><a href="/wiki/Smack_(software)" title="Smack (software)">Smack</a></li> <li><a href="/wiki/Tomoyo_Linux" title="Tomoyo Linux">Tomoyo Linux</a></li> <li><a href="/wiki/Linux_PAM" title="Linux PAM">Linux PAM</a></li></ul> <ul><li><a href="/wiki/Device_driver" title="Device driver">Device drivers</a> <ul><li><a href="/wiki/Comparison_of_open-source_wireless_drivers" title="Comparison of open-source wireless drivers">802.11</a></li> <li><a href="/wiki/Free_and_open-source_graphics_device_driver" title="Free and open-source graphics device driver">graphics</a></li></ul></li> <li><a href="/wiki/Raw_device" title="Raw device">Raw device</a></li></ul> <ul><li><a href="/wiki/Initramfs" class="mw-redirect" title="Initramfs">initramfs</a></li> <li><a href="/wiki/KernelCare" title="KernelCare">KernelCare</a></li> <li><a href="/wiki/Kexec" title="Kexec">kexec</a></li> <li><a href="/wiki/KGraft" title="KGraft">kGraft</a></li> <li><a href="/wiki/Kpatch" title="Kpatch">kpatch</a></li> <li><a href="/wiki/Ksplice" title="Ksplice">Ksplice</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Variants</th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Mainline_Linux" class="mw-redirect" title="Mainline Linux">Mainline</a> <ul><li><a href="/wiki/Linux_kernel" title="Linux kernel">Linux kernel</a></li> <li><a href="/wiki/Linux-libre" title="Linux-libre">Linux-libre</a></li></ul></li> <li><a href="/wiki/High-performance_computing" title="High-performance computing">High-performance computing</a> <ul><li><a href="/wiki/INK_(operating_system)" title="INK (operating system)">INK</a></li> <li><a href="/wiki/Compute_Node_Linux" title="Compute Node Linux">Compute Node Linux</a></li> <li><a href="/wiki/Slurm_Workload_Manager" title="Slurm Workload Manager">SLURM</a></li></ul></li> <li><a href="/wiki/Real-time_computing" title="Real-time computing">Real-time computing</a> <ul><li><a href="/wiki/RTLinux" title="RTLinux">RTLinux</a></li> <li><a href="/wiki/RTAI" title="RTAI">RTAI</a></li> <li><a href="/wiki/Xenomai" title="Xenomai">Xenomai</a></li> <li><a href="/wiki/PREEMPT_RT" title="PREEMPT RT">PREEMPT_RT</a></li></ul></li> <li><a href="/wiki/Memory_management_unit" title="Memory management unit">MMU</a>-less <ul><li><a href="/wiki/%CE%9CClinux" title="ΜClinux">μClinux</a></li> <li><a href="/wiki/PSXLinux" title="PSXLinux">PSXLinux</a></li></ul></li></ul> </div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Virtualization18" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Virtualization" title="Virtualization">Virtualization</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Hypervisor" title="Hypervisor">Hypervisor</a> <ul><li><a href="/wiki/Kernel-based_Virtual_Machine" title="Kernel-based Virtual Machine">KVM</a></li> <li><a href="/wiki/Xen" title="Xen">Xen</a></li></ul></li> <li><a href="/wiki/OS-level_virtualization" title="OS-level virtualization">OS-level virtualization</a> <ul><li><a href="/wiki/Linux-VServer" title="Linux-VServer">Linux-VServer</a></li> <li><a href="/wiki/Lguest" title="Lguest">Lguest</a></li> <li><a href="/wiki/LXC" title="LXC">LXC</a></li> <li><a href="/wiki/OpenVZ" title="OpenVZ">OpenVZ</a></li></ul></li> <li>Other <ul><li><a href="/wiki/L4Linux" title="L4Linux">L4Linux</a></li> <li><a href="/wiki/ELinOS" title="ELinOS">ELinOS</a></li> <li><a href="/wiki/User-mode_Linux" title="User-mode Linux">User-mode Linux</a></li> <li><a href="/wiki/MkLinux" title="MkLinux">MkLinux</a></li> <li><a href="/wiki/Cooperative_Linux" title="Cooperative Linux">coLinux</a></li></ul></li></ul> </div></td></tr></tbody></table><div> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_adoption" title="Linux adoption">Adoption</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th id="Rangeof_use48" scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_range_of_use" title="Linux range of use">Range<br />of use</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Linux_desktop_environments" class="mw-redirect" title="Linux desktop environments">Desktop</a></li> <li><a href="/wiki/Linux_on_embedded_systems" title="Linux on embedded systems">Embedded</a></li> <li><a href="/wiki/Video_games_and_Linux" title="Video games and Linux">Gaming</a></li> <li>Thin client: <ul><li><a href="/wiki/Linux_Terminal_Server_Project" title="Linux Terminal Server Project">LTSP</a></li></ul></li> <li>Server: <ul><li><a href="/wiki/LAMP_(software_bundle)" title="LAMP (software bundle)">LAMP</a></li> <li><a href="/wiki/LYME_(software_bundle)" title="LYME (software bundle)">LYME-LYCE</a></li></ul></li> <li><a href="/wiki/Linux-powered_device" title="Linux-powered device">Devices</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Adopters</th><td class="navbox-list-with-group navbox-list navbox-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/List_of_Linux_adopters" title="List of Linux adopters">List of Linux adopters</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><b><span class="nowrap"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:NewTux.svg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/13px-NewTux.svg.png" decoding="async" width="13" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/20px-NewTux.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/27px-NewTux.svg.png 2x" data-file-width="625" data-file-height="750" /></a></span> </span><a href="/wiki/Portal:Linux" title="Portal:Linux">Linux portal</a></b></li> <li><b><span class="nowrap"><span class="noviewer" typeof="mw:File"><span><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/16px-Free_and_open-source_software_logo_%282009%29.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/24px-Free_and_open-source_software_logo_%282009%29.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/32px-Free_and_open-source_software_logo_%282009%29.svg.png 2x" data-file-width="512" data-file-height="512" /></span></span> </span><a href="/wiki/Portal:Free_and_open-source_software" title="Portal:Free and open-source software">Free and open-source software portal</a></b></li> <li><span class="noviewer" typeof="mw:File"><span title="Category"><img alt="" src="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/16px-Symbol_category_class.svg.png" decoding="async" width="16" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/23px-Symbol_category_class.svg.png 1.5x, //upload.wikimedia.org/wikipedia/en/thumb/9/96/Symbol_category_class.svg/31px-Symbol_category_class.svg.png 2x" data-file-width="180" data-file-height="185" /></span></span> <b><a href="/wiki/Category:Linux_kernel" title="Category:Linux kernel">Category</a></b></li></ul> </div></td></tr></tbody></table></div> <div class="navbox-styles"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1236075235"></div><div role="navigation" class="navbox" aria-labelledby="Linux642" style="padding:3px"><table class="nowraplinks hlist mw-collapsible autocollapse navbox-inner" style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Linux" title="Template:Linux"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Linux" title="Template talk:Linux"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Linux" title="Special:EditPage/Template:Linux"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Linux642" style="font-size:114%;margin:0 4em"><a href="/wiki/Linux" title="Linux">Linux</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_kernel" title="Linux kernel">Linux kernel</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/History_of_Linux" title="History of Linux">History</a></li> <li><a href="/wiki/Linus%27s_law" title="Linus's law">Linus's law</a></li> <li><a href="/wiki/Linux-libre" title="Linux-libre">Linux-libre</a></li> <li><a href="/wiki/Booting_process_of_Linux" title="Booting process of Linux">Booting process</a></li> <li><a href="/wiki/Linux_kernel_oops" title="Linux kernel oops">Kernel oops</a></li> <li><a href="/wiki/Tux_(mascot)" title="Tux (mascot)">Tux</a></li> <li><i><a href="/wiki/Template:Linux_kernel" title="Template:Linux kernel">more…</a></i></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Controversies</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Criticism_of_Linux" title="Criticism of Linux">Criticism of Linux</a></li> <li><a href="/wiki/Criticism_of_desktop_Linux" title="Criticism of desktop Linux">Criticism of desktop Linux</a></li> <li><a href="/wiki/GNU/Linux_naming_controversy" title="GNU/Linux naming controversy">GNU/Linux naming controversy</a></li> <li><a href="/wiki/Tanenbaum%E2%80%93Torvalds_debate" title="Tanenbaum–Torvalds debate">Tanenbaum–Torvalds debate</a></li> <li><a href="/wiki/SCO%E2%80%93Linux_disputes" title="SCO–Linux disputes">SCO and Linux</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_distribution" title="Linux distribution">Distributions</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Comparison_of_Linux_distributions" title="Comparison of Linux distributions">General comparison</a></li> <li><a href="/wiki/List_of_Linux_distributions" title="List of Linux distributions">Distributions list</a></li> <li><a href="/wiki/Comparison_of_netbook-oriented_Linux_distributions" title="Comparison of netbook-oriented Linux distributions">Netbook-specific comparison</a></li> <li><a href="/wiki/List_of_Linux_distributions_that_run_from_RAM" title="List of Linux distributions that run from RAM">Distributions that run from RAM</a></li> <li><a href="/wiki/Light-weight_Linux_distribution" title="Light-weight Linux distribution">Lightweight</a></li> <li><a href="/wiki/Security-focused_operating_system#Linux" title="Security-focused operating system">Security-focused operating system</a></li> <li><a href="/wiki/Package_manager" title="Package manager">Package manager</a> <ul><li><a href="/wiki/Package_format" title="Package format">Package format</a></li> <li><a href="/wiki/List_of_software_package_management_systems" title="List of software package management systems">List of software package managers</a></li></ul></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Organizations</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/LinuxChix" title="LinuxChix">LinuxChix</a></li> <li><a href="/wiki/Linux_Counter" title="Linux Counter">Linux Counter</a></li> <li><a href="/wiki/Linux_Documentation_Project" title="Linux Documentation Project">Linux Documentation Project</a></li> <li><a href="/wiki/Linux_Foundation" title="Linux Foundation">Linux Foundation</a></li> <li><a href="/wiki/Linux_Mark_Institute" title="Linux Mark Institute">Linux Mark Institute</a></li> <li><a href="/wiki/Linux_user_group" title="Linux user group">Linux User Group (LUG)</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Linux_adoption" title="Linux adoption">Adoption</a></th><td class="navbox-list-with-group 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href="/wiki/DistroWatch" title="DistroWatch">DistroWatch</a></li> <li><i><a href="/wiki/Free_Software_Magazine" title="Free Software Magazine">Free Software Magazine</a></i></li> <li><i><a href="/wiki/Full_Circle_(magazine)" title="Full Circle (magazine)">Full Circle</a></i></li> <li><i><a href="/wiki/Hacker_Public_Radio" title="Hacker Public Radio">Hacker Public Radio</a></i></li> <li><a href="/wiki/Linux.com" title="Linux.com">Linux.com</a></li> <li><i><a href="/wiki/Linux_Format" title="Linux Format">Linux Format</a></i></li> <li><i><a href="/wiki/Linux_Gazette" title="Linux Gazette">Linux Gazette</a></i></li> <li><i><a href="/wiki/Linux_Journal" title="Linux Journal">Linux Journal</a></i></li> <li><i><a href="/wiki/Linux_Magazine" title="Linux Magazine">Linux Magazine</a></i></li> <li><i><a href="/wiki/LinuxUser" title="LinuxUser">LinuxUser</a></i> <ul><li><i><a href="/wiki/Ubuntu_User" title="Ubuntu User">Ubuntu User</a></i></li></ul></li> <li><a href="/wiki/Linux_Outlaws" title="Linux Outlaws">Linux Outlaws</a></li> <li><i><a href="/wiki/Linux_Voice" title="Linux Voice">Linux Voice</a></i></li> <li><a href="/wiki/LugRadio" title="LugRadio">LugRadio</a></li> <li><a href="/wiki/LWN.net" title="LWN.net">LWN.net</a></li> <li><a href="/wiki/Phoronix_Test_Suite#Phoronix_website" title="Phoronix Test Suite">Phoronix</a></li> <li><i><a href="/wiki/Revolution_OS" title="Revolution OS">Revolution OS</a></i></li> <li><a href="/wiki/The_Code_(2001_film)" title="The Code (2001 film)"><i>The Code</i></a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/List_of_computer_security_certifications" title="List of computer security certifications">Professional related certifications</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CompTIA_Linux%2B" class="mw-redirect" title="CompTIA Linux+">CompTIA Linux+</a></li> <li><a href="/wiki/Linux_Foundation_Linux_Certification" class="mw-redirect" title="Linux Foundation Linux Certification">Linux Foundation</a></li> <li><a href="/wiki/Red_Hat_Certification_Program" title="Red Hat Certification Program">Red Hat</a></li> <li><a href="/wiki/Ubuntu_Professional_Certification" title="Ubuntu Professional Certification">Ubuntu</a></li></ul> </div></td></tr><tr><td class="navbox-abovebelow" colspan="2"><div> <ul><li><b><span class="nowrap"><span class="noviewer" typeof="mw:File"><a href="/wiki/File:NewTux.svg" class="mw-file-description"><img alt="icon" src="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/13px-NewTux.svg.png" decoding="async" width="13" height="16" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/20px-NewTux.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/27px-NewTux.svg.png 2x" data-file-width="625" data-file-height="750" /></a></span> </span><a 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style="border-spacing:0;background:transparent;color:inherit"><tbody><tr><th scope="col" class="navbox-title" colspan="2"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1129693374"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1239400231"><div class="navbar plainlinks hlist navbar-mini"><ul><li class="nv-view"><a href="/wiki/Template:Operating_systems" title="Template:Operating systems"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Operating_systems" title="Template talk:Operating systems"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Operating_systems" title="Special:EditPage/Template:Operating systems"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Operating_systems310" style="font-size:114%;margin:0 4em"><a href="/wiki/Operating_system" title="Operating system">Operating systems</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">General</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Comparison_of_operating_systems" title="Comparison of operating systems">Comparison</a></li> <li><a href="/wiki/Forensic_software_engineering" title="Forensic software engineering">Forensic engineering</a></li> <li><a href="/wiki/History_of_operating_systems" title="History of operating systems">History</a></li> <li><a href="/wiki/List_of_operating_systems" title="List of operating systems">List</a></li> <li><a href="/wiki/Timeline_of_operating_systems" title="Timeline of operating systems">Timeline</a></li> <li><a href="/wiki/Usage_share_of_operating_systems" title="Usage share of operating systems">Usage share</a></li> <li><a href="/wiki/Comparison_of_user_features_of_operating_systems" title="Comparison of user features of operating systems">User features comparison</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Variants</th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Disk_operating_system" title="Disk operating system">Disk operating system</a></li> <li><a href="/wiki/Distributed_operating_system" title="Distributed operating system">Distributed operating system</a></li> <li><a href="/wiki/Embedded_operating_system" title="Embedded operating system">Embedded operating system</a></li> <li><a href="/wiki/Hobbyist_operating_system" title="Hobbyist operating system">Hobbyist operating system</a></li> <li><a href="/wiki/Just_enough_operating_system" title="Just enough operating system">Just enough operating system</a></li> <li><a href="/wiki/Mobile_operating_system" title="Mobile operating system">Mobile operating system</a></li> <li><a href="/wiki/Network_operating_system" title="Network operating system">Network operating system</a></li> <li><a href="/wiki/Object-oriented_operating_system" title="Object-oriented operating system">Object-oriented operating system</a></li> <li><a href="/wiki/Real-time_operating_system" title="Real-time operating system">Real-time operating system</a></li> <li><a href="/wiki/Supercomputer_operating_system" title="Supercomputer operating system">Supercomputer operating system</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Kernel_(operating_system)" title="Kernel (operating system)">Kernel</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:6em"><a href="/wiki/Computer_architecture" title="Computer architecture">Architectures</a></th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Exokernel" title="Exokernel">Exokernel</a></li> <li><a href="/wiki/Hybrid_kernel" title="Hybrid kernel">Hybrid</a></li> <li><a href="/wiki/Microkernel" title="Microkernel">Microkernel</a></li> <li><a href="/wiki/Monolithic_kernel" title="Monolithic kernel">Monolithic</a></li> <li><a href="/wiki/Multikernel" title="Multikernel">Multikernel</a></li> <li><a href="/wiki/Vkernel" title="Vkernel">vkernel</a></li> <li><a href="/wiki/Rump_kernel" title="Rump kernel">Rump kernel</a></li> <li><a href="/wiki/Unikernel" title="Unikernel">Unikernel</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:6em">Components</th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Device_driver" title="Device driver">Device driver</a></li> <li><a href="/wiki/Loadable_kernel_module" title="Loadable kernel module">Loadable kernel module</a></li> <li><a href="/wiki/User_space_and_kernel_space" title="User space and kernel space">User space and kernel space</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Process_management_(computing)" title="Process management (computing)">Process management</a></th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"></div><table class="nowraplinks navbox-subgroup" style="border-spacing:0"><tbody><tr><th scope="row" class="navbox-group" style="width:6em">Concepts</th><td class="navbox-list-with-group navbox-list navbox-odd" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Computer_multitasking" title="Computer multitasking">Computer multitasking</a> (<a href="/wiki/Cooperative_multitasking" title="Cooperative multitasking">Cooperative</a>, <a href="/wiki/Preemption_(computing)" title="Preemption (computing)">Preemptive</a>)</li> <li><a href="/wiki/Context_switch" title="Context switch">Context switch</a></li> <li><a href="/wiki/Interrupt" title="Interrupt">Interrupt</a></li> <li><a href="/wiki/Inter-process_communication" title="Inter-process communication">IPC</a></li> <li><a href="/wiki/Process_(computing)" title="Process (computing)">Process</a></li> <li><a href="/wiki/Process_control_block" title="Process control block">Process control block</a></li> <li><a href="/wiki/Real-time_operating_system" title="Real-time operating system">Real-time</a></li> <li><a href="/wiki/Thread_(computing)" title="Thread (computing)">Thread</a></li> <li><a href="/wiki/Time-sharing" title="Time-sharing">Time-sharing</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:6em"><a href="/wiki/Scheduling_(computing)" title="Scheduling (computing)">Scheduling<br />algorithms</a></th><td class="navbox-list-with-group navbox-list navbox-even" style="padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Fixed-priority_pre-emptive_scheduling" title="Fixed-priority pre-emptive scheduling">Fixed-priority preemptive</a></li> <li><a href="/wiki/Multilevel_feedback_queue" title="Multilevel feedback queue">Multilevel feedback queue</a></li> <li><a href="/wiki/Round-robin_scheduling" title="Round-robin scheduling">Round-robin</a></li> <li><a href="/wiki/Shortest_job_next" title="Shortest job next">Shortest job next</a></li></ul> </div></td></tr></tbody></table><div></div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Memory_management_(operating_systems)" title="Memory management (operating systems)">Memory management</a>,<br /><a href="/wiki/System_resource" title="System resource">resource</a> protection</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Bus_error" title="Bus error">Bus error</a></li> <li><a href="/wiki/General_protection_fault" title="General protection fault">General protection fault</a></li> <li><a href="/wiki/Memory_paging" title="Memory paging">Memory paging</a></li> <li><a href="/wiki/Memory_protection" title="Memory protection">Memory protection</a></li> <li><a href="/wiki/Protection_ring" title="Protection ring">Protection ring</a></li> <li><a href="/wiki/Segmentation_fault" title="Segmentation fault">Segmentation fault</a></li> <li><a href="/wiki/Virtual_memory" title="Virtual memory">Virtual memory</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%"><a href="/wiki/Non-volatile_memory" title="Non-volatile memory">Storage</a> access,<br /><a href="/wiki/File_system" title="File system">file systems</a></th><td class="navbox-list-with-group navbox-list navbox-even hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/Booting#BOOT-LOADER" title="Booting">Boot loader</a></li> <li><a href="/wiki/Defragmentation" title="Defragmentation">Defragmentation</a></li> <li><a href="/wiki/Device_file" title="Device file">Device file</a></li> <li><a href="/wiki/File_attribute" title="File attribute">File attribute</a></li> <li><a href="/wiki/Inode" title="Inode">Inode</a></li> <li><a href="/wiki/Journaling_file_system" title="Journaling file system">Journal</a></li> <li><a href="/wiki/Disk_partitioning" title="Disk partitioning">Partition</a></li> <li><a href="/wiki/Virtual_file_system" title="Virtual file system">Virtual file system</a></li> <li><a href="/wiki/Virtual_tape_library" title="Virtual tape library">Virtual tape library</a></li></ul> </div></td></tr><tr><th scope="row" class="navbox-group" style="width:1%">Supporting concepts</th><td class="navbox-list-with-group navbox-list navbox-odd hlist" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a 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