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mw-first-heading">ftrace</h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Go to an article in another language. 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class="mw-body-content"><div class="mw-content-ltr mw-parser-output" lang="en" dir="ltr"><div class="shortdescription nomobile noexcerpt noprint searchaux" style="display:none">Tracing utility for Linux kernel</div> <p class="mw-empty-elt"> </p> <style data-mw-deduplicate="TemplateStyles:r1257001546">.mw-parser-output .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">ftrace</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">Steven Rostedt and others</td></tr><tr><th scope="row" class="infobox-label" style="white-space: nowrap;">Initial release</th><td class="infobox-data">October 9, 2008<span class="noprint">; 16 years ago</span><span style="display:none"> (<span class="bday dtstart published updated">2008-10-09</span>)</span></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/Kernel_extension" class="mw-redirect" title="Kernel extension">Kernel extension</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> version 2<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></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="https://www.kernel.org/doc/html/latest/trace/index.html">www<wbr />.kernel<wbr />.org<wbr />/doc<wbr />/html<wbr />/latest<wbr />/trace<wbr />/index<wbr />.html</a></span></td></tr></tbody></table> <p><b>ftrace</b> (<b>Function Tracer</b>) is a <a href="/wiki/Tracing_(software)" title="Tracing (software)">tracing</a> <a href="/wiki/Software_framework" title="Software framework">framework</a> for the <a href="/wiki/Linux_kernel" title="Linux kernel">Linux kernel</a>. Although its original name, Function Tracer, came from ftrace's ability to record information related to various <a href="/wiki/Function_call" class="mw-redirect" title="Function call">function calls</a> performed while the <a href="/wiki/Kernel_(operating_system)" title="Kernel (operating system)">kernel</a> is running, ftrace's tracing capabilities cover a much broader range of kernel's internal operations.<sup id="cite_ref-lwn-322666_2-0" class="reference"><a href="#cite_note-lwn-322666-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-kernel_3-0" class="reference"><a href="#cite_note-kernel-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Details">Details</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Ftrace&action=edit&section=1" title="Edit section: Details"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>With its various tracer plugins, ftrace can be targeted at different static <b>tracepoints</b>, such as <a href="/wiki/Scheduling_(computing)" title="Scheduling (computing)">scheduling</a> events, <a href="/wiki/Interrupt" title="Interrupt">interrupts</a>, <a href="/wiki/Memory-mapped_I/O" class="mw-redirect" title="Memory-mapped I/O">memory-mapped I/O</a>, <a href="/wiki/CPU_power_state" class="mw-redirect" title="CPU power state">CPU power state</a> transitions, and operations related to <a href="/wiki/File_system" title="File system">file systems</a> and <a href="/wiki/Virtualization" title="Virtualization">virtualization</a>. Also, dynamic tracking of kernel function calls is available, optionally restrictable to a subset of <a href="/wiki/Function_(programming)" class="mw-redirect" title="Function (programming)">functions</a> by using <a href="/wiki/Glob_(programming)" title="Glob (programming)">globs</a>, and with the possibility to generate <a href="/wiki/Call_graph" title="Call graph">call graphs</a> and provide <a href="/wiki/Call_stack" title="Call stack">stack</a> usage reports. At the same time, ftrace can be used to measure various <a href="/wiki/Latency_(engineering)" title="Latency (engineering)">latencies</a> within the Linux kernel, such as for how long interrupts or <a href="/wiki/Linux_kernel_preemption" class="mw-redirect" title="Linux kernel preemption">preemption</a> are disabled.<sup id="cite_ref-lwn-322666_2-1" class="reference"><a href="#cite_note-lwn-322666-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-4" class="reference"><a href="#cite_note-4"><span class="cite-bracket">[</span>4<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-linuxcon_5-0" class="reference"><a href="#cite_note-linuxcon-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 3–11, 14, 18">: 3–11, 14, 18 </span></sup> </p><p>An ftrace-enabled Linux kernel is built by enabling the <style data-mw-deduplicate="TemplateStyles:r886049734">.mw-parser-output .monospaced{font-family:monospace,monospace}</style><span class="monospaced">CONFIG_FUNCTION_TRACER</span> <a href="/wiki/Linux_kernel_configuration" class="mw-redirect" title="Linux kernel configuration">kernel configuration</a> option. The entire runtime interaction with ftrace is performed through readable and writable <a href="/wiki/Virtual_file" class="mw-redirect" title="Virtual file">virtual files</a> contained in a specifically mounted <a href="/wiki/Debugfs" title="Debugfs">debugfs</a> file system; as a result, ftrace requires no specialized <a href="/wiki/Userspace" class="mw-redirect" title="Userspace">userspace</a> utilities to operate.<sup id="cite_ref-lwn-322666_2-2" class="reference"><a href="#cite_note-lwn-322666-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-kernel_3-1" class="reference"><a href="#cite_note-kernel-3"><span class="cite-bracket">[</span>3<span class="cite-bracket">]</span></a></sup><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> However, there are additional userspace utilities that provide more advanced features for data recording, analysis and visualization; examples of such utilities are <i>trace-cmd</i> and <i>KernelShark</i>.<sup id="cite_ref-lwn-322666_2-3" class="reference"><a href="#cite_note-lwn-322666-2"><span class="cite-bracket">[</span>2<span class="cite-bracket">]</span></a></sup><sup id="cite_ref-linuxcon_5-1" class="reference"><a href="#cite_note-linuxcon-5"><span class="cite-bracket">[</span>5<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 31–47">: 31–47 </span></sup><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><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> </p><p>Internally, ftrace relies on the <a href="/wiki/GNU_Compiler_Collection" title="GNU Compiler Collection">gcc</a>'s <a href="/wiki/Profiling_(computer_programming)" title="Profiling (computer programming)">profiling</a> mechanism to prepend <a href="/wiki/Machine_instruction" class="mw-redirect" title="Machine instruction">machine instructions</a> to the <a href="/wiki/Compile" class="mw-redirect" title="Compile">compiled</a> versions of all <a href="/wiki/Source_code" title="Source code">source</a>-level kernel functions, which redirect the execution of functions to the ftrace's <a href="/wiki/Trampoline_(computing)" title="Trampoline (computing)">trampolines</a> and tracer plugins that perform the actual tracing. These "<a href="/wiki/Entry_point" title="Entry point">entry point</a>" instructions created by gcc are altered by ftrace when the kernel is <a href="/wiki/Booting" title="Booting">booted</a>, and varied later at runtime by ftrace between <a href="/wiki/NOP_(code)" title="NOP (code)">NOPs</a> and actual <a href="/wiki/Unconditional_branch" class="mw-redirect" title="Unconditional branch">jumps</a> to the tracing trampolines, depending on the tracing types and options configured at runtime.<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-10" class="reference"><a href="#cite_note-10"><span class="cite-bracket">[</span>10<span class="cite-bracket">]</span></a></sup> </p><p>ftrace is developed primarily by Steven Rostedt, and 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 2.6.27, which was released on October 9, 2008.<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> </p> <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=Ftrace&action=edit&section=2" 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 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portal</a></span></li></ul> <ul><li><a href="/wiki/DTrace" title="DTrace">DTrace</a> –  a tracing framework for troubleshooting kernel and application problems, originally developed for Solaris</li> <li><a href="/wiki/Ktrace" title="Ktrace">ktrace</a> –  a BSD Unix and Mac OS X utility that traces kernel–program interactions</li> <li><a href="/wiki/Ltrace" title="Ltrace">ltrace</a> –  a Linux debugging utility, displays the calls a userland application makes to shared libraries</li> <li><a href="/wiki/Strace" title="Strace">strace</a> –  a debugging utility for Linux and some other Unix-like systems, monitors system calls used by a program and all received signals</li> <li><a href="/wiki/SystemTap" title="SystemTap">SystemTap</a> –  a scripting language and utility used for instrumenting Linux systems</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=Ftrace&action=edit&section=3" 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 .reflist-columns-2{column-width:30em}.mw-parser-output .reflist-columns-3{column-width:25em}.mw-parser-output .reflist-columns{margin-top:0.3em}.mw-parser-output .reflist-columns ol{margin-top:0}.mw-parser-output .reflist-columns li{page-break-inside:avoid;break-inside:avoid-column}.mw-parser-output .reflist-upper-alpha{list-style-type:upper-alpha}.mw-parser-output .reflist-upper-roman{list-style-type:upper-roman}.mw-parser-output .reflist-lower-alpha{list-style-type:lower-alpha}.mw-parser-output .reflist-lower-greek{list-style-type:lower-greek}.mw-parser-output .reflist-lower-roman{list-style-type:lower-roman}</style><div class="reflist"> <div class="mw-references-wrap mw-references-columns"><ol class="references"> <li id="cite_note-1"><span class="mw-cite-backlink"><b><a href="#cite_ref-1">^</a></b></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r1238218222">.mw-parser-output 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://www.kernel.org/pub/linux/kernel/COPYING">"Linux kernel source: kernel/COPYING file"</a>. <i>kernel.org</i>. 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Retrieved <span class="nowrap">July 23,</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%2Ftrace%2Fftrace.txt&rft.pub=kernel.org&rft.date=2014-06-16&rft.au=Steven+Rostedt&rft_id=https%3A%2F%2Fwww.kernel.org%2Fdoc%2FDocumentation%2Ftrace%2Fftrace.txt&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" class="Z3988"></span></span> </li> <li id="cite_note-4"><span class="mw-cite-backlink"><b><a href="#cite_ref-4">^</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://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_MRG/2/html/Realtime_Tuning_Guide/sect-Realtime_Tuning_Guide-Realtime_Specific_Tuning-Using_the_ftrace_Utility_for_Tracing_Latencies.html">"Red Hat Enterprise MRG 2 documentation, Section 3.8. Using the ftrace utility for tracing latencies"</a>. <a href="/wiki/Red_Hat" title="Red Hat">Red Hat</a>. May 23, 2014<span class="reference-accessdate">. Retrieved <span class="nowrap">July 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=Red+Hat+Enterprise+MRG+2+documentation%2C+Section+3.8.+Using+the+ftrace+utility+for+tracing+latencies&rft.pub=Red+Hat&rft.date=2014-05-23&rft_id=https%3A%2F%2Faccess.redhat.com%2Fdocumentation%2Fen-US%2FRed_Hat_Enterprise_MRG%2F2%2Fhtml%2FRealtime_Tuning_Guide%2Fsect-Realtime_Tuning_Guide-Realtime_Specific_Tuning-Using_the_ftrace_Utility_for_Tracing_Latencies.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" class="Z3988"></span></span> </li> <li id="cite_note-linuxcon-5"><span class="mw-cite-backlink">^ <a href="#cite_ref-linuxcon_5-0"><sup><i><b>a</b></i></sup></a> <a href="#cite_ref-linuxcon_5-1"><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="CITEREFSteven_Rostedt2010" class="citation web cs1">Steven Rostedt (October 18, 2010). <a rel="nofollow" class="external text" href="https://web.archive.org/web/20130308164230/http://events.linuxfoundation.org/slides/2010/linuxcon_japan/linuxcon_jp2010_rostedt.pdf">"Ftrace: Linux Kernel Tracing"</a> <span class="cs1-format">(PDF)</span>. <i>linuxfoundation.org</i>. Archived from <a rel="nofollow" class="external text" href="https://events.linuxfoundation.org/slides/2010/linuxcon_japan/linuxcon_jp2010_rostedt.pdf">the original</a> <span class="cs1-format">(PDF)</span> on March 8, 2013<span class="reference-accessdate">. Retrieved <span class="nowrap">July 23,</span> 2014</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=linuxfoundation.org&rft.atitle=Ftrace%3A+Linux+Kernel+Tracing&rft.date=2010-10-18&rft.au=Steven+Rostedt&rft_id=https%3A%2F%2Fevents.linuxfoundation.org%2Fslides%2F2010%2Flinuxcon_japan%2Flinuxcon_jp2010_rostedt.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" class="Z3988"></span></span> </li> <li id="cite_note-6"><span class="mw-cite-backlink"><b><a href="#cite_ref-6">^</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://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/6/html/Developer_Guide/ftrace.html">"Red Hat Enterprise Linux 6 documentation, Section 6.5. ftrace"</a>. <a href="/wiki/Red_Hat" title="Red Hat">Red Hat</a>. 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Retrieved <span class="nowrap">July 23,</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=Red+Hat+Enterprise+Linux+6+documentation%2C+Section+6.5.+ftrace&rft.pub=Red+Hat&rft.date=2014-03-14&rft_id=https%3A%2F%2Faccess.redhat.com%2Fdocumentation%2Fen-US%2FRed_Hat_Enterprise_Linux%2F6%2Fhtml%2FDeveloper_Guide%2Fftrace.html&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" 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="CITEREFSteven_Rostedt2010" class="citation web cs1">Steven Rostedt (October 20, 2010). <a rel="nofollow" class="external text" href="https://lwn.net/Articles/410200/">"trace-cmd: A front-end for Ftrace"</a>. <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a><span class="reference-accessdate">. Retrieved <span class="nowrap">January 19,</span> 2015</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=unknown&rft.btitle=trace-cmd%3A+A+front-end+for+Ftrace&rft.pub=LWN.net&rft.date=2010-10-20&rft.au=Steven+Rostedt&rft_id=https%3A%2F%2Flwn.net%2FArticles%2F410200%2F&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" 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="CITEREFSteven_Rostedt2011" class="citation web cs1">Steven Rostedt (February 2, 2011). <a rel="nofollow" class="external text" href="https://lwn.net/Articles/425583/">"Using KernelShark to analyze the real-time scheduler"</a>. <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a><span class="reference-accessdate">. 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Retrieved <span class="nowrap">June 11,</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=linuxplumbersconf.org&rft.atitle=Ftrace+Kernel+Hooks%3A+More+than+just+tracing&rft.pages=%3Cspan+class%3D%22nowrap%22%3E6-%3C%2Fspan%3E12%2C+24%2C+34%2C+%3Cspan+class%3D%22nowrap%22%3E56-%3C%2Fspan%3E58&rft.date=2015-01-05&rft.au=Steven+Rostedt&rft_id=http%3A%2F%2Fwww.linuxplumbersconf.org%2F2014%2Focw%2Fsystem%2Fpresentations%2F1773%2Foriginal%2Fftrace-kernel-hooks-2014.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" class="Z3988"></span></span> </li> <li id="cite_note-10"><span class="mw-cite-backlink"><b><a href="#cite_ref-10">^</a></b></span> <span class="reference-text"><link rel="mw-deduplicated-inline-style" href="mw-data:TemplateStyles:r1238218222" /><cite id="CITEREFTim_Bird2012" class="citation web cs1">Tim Bird (November 1, 2012). <a rel="nofollow" class="external text" href="http://elinux.org/images/d/d6/Measuring-function-duration-with-ftrace.pdf">"Measuring Function Duration with Ftrace"</a> <span class="cs1-format">(PDF)</span>. <i>elinux.org</i>. pp. <span class="nowrap">5–</span>6, <span class="nowrap">12–</span>14<span class="reference-accessdate">. Retrieved <span class="nowrap">June 11,</span> 2016</span>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal&rft.genre=unknown&rft.jtitle=elinux.org&rft.atitle=Measuring+Function+Duration+with+Ftrace&rft.pages=%3Cspan+class%3D%22nowrap%22%3E5-%3C%2Fspan%3E6%2C+%3Cspan+class%3D%22nowrap%22%3E12-%3C%2Fspan%3E14&rft.date=2012-11-01&rft.au=Tim+Bird&rft_id=http%3A%2F%2Felinux.org%2Fimages%2Fd%2Fd6%2FMeasuring-function-duration-with-ftrace.pdf&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" 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 class="citation web cs1"><a rel="nofollow" class="external text" href="http://kernelnewbies.org/Linux_2_6_27#head-27c23aa79ee6da975ef95b4fff381ace1667a264">"Linux kernel 2.6.27, Section 1.7. ftrace, sysprof support"</a>. <i>kernelnewbies.org</i>. October 9, 2008<span class="reference-accessdate">. Retrieved <span class="nowrap">July 23,</span> 2014</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+2.6.27%2C+Section+1.7.+ftrace%2C+sysprof+support&rft.date=2008-10-09&rft_id=http%3A%2F%2Fkernelnewbies.org%2FLinux_2_6_27%23head-27c23aa79ee6da975ef95b4fff381ace1667a264&rfr_id=info%3Asid%2Fen.wikipedia.org%3AFtrace" class="Z3988"></span></span> </li> </ol></div></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=Ftrace&action=edit&section=4" title="Edit section: External links"><span>edit</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a rel="nofollow" class="external text" href="https://lwn.net/Articles/365835/">Debugging the kernel using Ftrace –  part 1</a> and <a rel="nofollow" class="external text" href="https://lwn.net/Articles/366796/">part 2</a>, <a href="/wiki/LWN.net" title="LWN.net">LWN.net</a>, December 2009, by Steven Rostedt</li> <li><a rel="nofollow" class="external text" href="https://lwn.net/Articles/370423/">Secrets of the Ftrace function tracer</a>, LWN.net, January 20, 2010, by Steven Rostedt</li> <li><a rel="nofollow" class="external text" href="https://lwn.net/Articles/608497/">Ftrace: The hidden light switch</a>, LWN.net, August 13, 2014, by Brendan Gregg</li> <li><a rel="nofollow" class="external text" href="https://lwn.net/Articles/304105/">The source of the e1000e corruption bug</a>, LWN.net, October 21, 2008, by Jonathan Corbet</li></ul> <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 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href="/wiki/Template:Linux_kernel" title="Template:Linux kernel"><abbr title="View this template">v</abbr></a></li><li class="nv-talk"><a href="/wiki/Template_talk:Linux_kernel" title="Template talk:Linux kernel"><abbr title="Discuss this template">t</abbr></a></li><li class="nv-edit"><a href="/wiki/Special:EditPage/Template:Linux_kernel" title="Special:EditPage/Template:Linux kernel"><abbr title="Edit this template">e</abbr></a></li></ul></div><div id="Linux_kernel514" style="font-size:114%;margin:0 4em"><a href="/wiki/Linux_kernel" title="Linux kernel">Linux kernel</a></div></th></tr><tr><th scope="row" class="navbox-group" style="width:1%">Organization</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="Kernel19" 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"> <ul><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/Linus%27s_law" title="Linus's law">Linus's law</a></li> <li><a href="/wiki/Tanenbaum%E2%80%93Torvalds_debate" title="Tanenbaum–Torvalds debate">Tanenbaum–Torvalds debate</a></li> <li><a href="/wiki/Tux_(mascot)" title="Tux (mascot)">Tux</a></li> <li><a href="/wiki/SCO%E2%80%93Linux_disputes" title="SCO–Linux disputes">SCO disputes</a></li> <li><a href="/wiki/Linaro" title="Linaro">Linaro</a></li> <li><a href="/wiki/GNU_General_Public_License#Version_2" title="GNU General Public License">GNU GPL v2</a></li> <li><a href="/wiki/Menuconfig" title="Menuconfig">menuconfig</a></li> <li><a href="/wiki/List_of_Linux-supported_computer_architectures" title="List of Linux-supported computer architectures">Supported 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><tr><th scope="row" class="navbox-group" style="width:1%">People</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/Werner_Almesberger" title="Werner Almesberger">Werner Almesberger</a></li> <li><a href="/wiki/H._Peter_Anvin" title="H. Peter Anvin">H. Peter Anvin</a></li> <li><a href="/wiki/Jens_Axboe" title="Jens Axboe">Jens Axboe</a></li> <li><a href="/wiki/Moshe_Bar_(investor)" title="Moshe Bar (investor)">Moshe Bar</a></li> <li><a href="/wiki/Suparna_Bhattacharya" title="Suparna Bhattacharya">Suparna Bhattacharya</a></li> <li><a href="/wiki/Andries_Brouwer" title="Andries Brouwer">Andries Brouwer</a></li> <li><a href="/wiki/R%C3%A9my_Card" title="Rémy Card">Rémy Card</a></li> <li><a href="/wiki/Alan_Cox_(computer_programmer)" title="Alan Cox (computer programmer)">Alan Cox</a></li> <li><a href="/wiki/Matthew_Garrett" title="Matthew Garrett">Matthew Garrett</a></li> <li><a href="/wiki/Avi_Kivity" title="Avi Kivity">Avi Kivity</a></li> <li><a href="/wiki/Con_Kolivas" title="Con Kolivas">Con Kolivas</a></li> <li><a href="/wiki/Greg_Kroah-Hartman" title="Greg Kroah-Hartman">Greg Kroah-Hartman</a></li> <li><a href="/wiki/Benson_Leung" title="Benson Leung">Benson Leung</a></li> <li><a href="/wiki/Robert_Love" title="Robert Love">Robert Love</a></li> <li><a href="/wiki/David_S._Miller" title="David S. Miller">David S. Miller</a></li> <li><a href="/wiki/Ingo_Moln%C3%A1r" title="Ingo Molnár">Ingo Molnár</a></li> <li><a href="/wiki/Andrew_Morton_(computer_programmer)" title="Andrew Morton (computer programmer)">Andrew Morton</a></li> <li><a href="/wiki/Hans_Reiser" title="Hans Reiser">Hans Reiser</a></li> <li><a href="/wiki/Rusty_Russell" title="Rusty Russell">Rusty Russell</a></li> <li><a href="/wiki/Shuah_Khan" title="Shuah Khan">Shuah Khan</a></li> <li><a href="/wiki/Linus_Torvalds" title="Linus Torvalds">Linus Torvalds</a></li> <li><a href="/wiki/Theodore_Ts%27o" title="Theodore Ts'o">Theodore Ts'o</a></li> <li><a href="/wiki/Stephen_Tweedie" title="Stephen Tweedie">Stephen Tweedie</a></li> <li><a href="/wiki/Harald_Welte" title="Harald Welte">Harald Welte</a></li> <li><a href="/wiki/Chris_Wright_(programmer)" title="Chris Wright (programmer)">Chris Wright</a></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-even" style="width:100%;padding:0"><div style="padding:0 0.25em"> <ul><li><a href="/wiki/CRIU" title="CRIU">CRIU</a></li> <li><a class="mw-selflink selflink">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-odd" 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-even" 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-odd" 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-even" 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-odd" 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> <li><a href="/wiki/Binfmt_misc" title="Binfmt misc">binfmt_misc</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-even" 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-odd" 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 href="/wiki/Bcache" title="Bcache">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-even" 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-odd" 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-even" 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-odd" 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/12px-NewTux.svg.png" decoding="async" width="12" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/19px-NewTux.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/b/b0/NewTux.svg/25px-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/15px-Free_and_open-source_software_logo_%282009%29.svg.png" decoding="async" width="15" height="15" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/31/Free_and_open-source_software_logo_%282009%29.svg/23px-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/30px-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="Operating_systems310" style="padding:3px"><table class="nowraplinks 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: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 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