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Diffstat (limited to 'man5/proc_timer_stats.5')
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diff --git a/man5/proc_timer_stats.5 b/man5/proc_timer_stats.5 deleted file mode 100644 index 0c9f45978..000000000 --- a/man5/proc_timer_stats.5 +++ /dev/null @@ -1,117 +0,0 @@ -.\" Copyright (C) 1994, 1995, Daniel Quinlan <quinlan@yggdrasil.com> -.\" Copyright (C) 2002-2008, 2017, Michael Kerrisk <mtk.manpages@gmail.com> -.\" Copyright (C) 2023, Alejandro Colomar <alx@kernel.org> -.\" -.\" SPDX-License-Identifier: GPL-3.0-or-later -.\" -.TH proc_timer_stats 5 (date) "Linux man-pages (unreleased)" -.SH NAME -/proc/timer_stats \- timer statistics -.SH DESCRIPTION -.TP -.IR /proc/timer_stats " (from Linux 2.6.21 until Linux 4.10)" -.\" commit 82f67cd9fca8c8762c15ba7ed0d5747588c1e221 -.\" Date: Fri Feb 16 01:28:13 2007 -0800 -.\" Text largely derived from Documentation/timers/timer_stats.txt -.\" removed in commit dfb4357da6ddbdf57d583ba64361c9d792b0e0b1 -.\" Date: Wed Feb 8 11:26:59 2017 -0800 -This is a debugging facility to make timer (ab)use in a Linux -system visible to kernel and user-space developers. -It can be used by kernel and user-space developers to verify that -their code does not make undue use of timers. -The goal is to avoid unnecessary wakeups, -thereby optimizing power consumption. -.IP -If enabled in the kernel -.RB ( CONFIG_TIMER_STATS ), -but not used, -it has almost zero run-time overhead and a relatively small -data-structure overhead. -Even if collection is enabled at run time, overhead is low: -all the locking is per-CPU and lookup is hashed. -.IP -The -.I /proc/timer_stats -file is used both to control sampling facility and to read out the -sampled information. -.IP -The -.I timer_stats -functionality is inactive on bootup. -A sampling period can be started using the following command: -.IP -.in +4n -.EX -# echo 1 > /proc/timer_stats -.EE -.in -.IP -The following command stops a sampling period: -.IP -.in +4n -.EX -# echo 0 > /proc/timer_stats -.EE -.in -.IP -The statistics can be retrieved by: -.IP -.in +4n -.EX -$ cat /proc/timer_stats -.EE -.in -.IP -While sampling is enabled, each readout from -.I /proc/timer_stats -will see -newly updated statistics. -Once sampling is disabled, the sampled information -is kept until a new sample period is started. -This allows multiple readouts. -.IP -Sample output from -.IR /proc/timer_stats : -.IP -.in +4n -.EX -.RB $ " cat /proc/timer_stats" -Timer Stats Version: v0.3 -Sample period: 1.764 s -Collection: active - 255, 0 swapper/3 hrtimer_start_range_ns (tick_sched_timer) - 71, 0 swapper/1 hrtimer_start_range_ns (tick_sched_timer) - 58, 0 swapper/0 hrtimer_start_range_ns (tick_sched_timer) - 4, 1694 gnome\-shell mod_delayed_work_on (delayed_work_timer_fn) - 17, 7 rcu_sched rcu_gp_kthread (process_timeout) -\&... - 1, 4911 kworker/u16:0 mod_delayed_work_on (delayed_work_timer_fn) - 1D, 2522 kworker/0:0 queue_delayed_work_on (delayed_work_timer_fn) -1029 total events, 583.333 events/sec -.EE -.in -.IP -The output columns are: -.RS -.IP [1] 5 -a count of the number of events, -optionally (since Linux 2.6.23) followed by the letter \[aq]D\[aq] -.\" commit c5c061b8f9726bc2c25e19dec227933a13d1e6b7 deferrable timers -if this is a deferrable timer; -.IP [2] -the PID of the process that initialized the timer; -.IP [3] -the name of the process that initialized the timer; -.IP [4] -the function where the timer was initialized; and -(in parentheses) -the callback function that is associated with the timer. -.RE -.IP -During the Linux 4.11 development cycle, -this file was removed because of security concerns, -as it exposes information across namespaces. -Furthermore, it is possible to obtain -the same information via in-kernel tracing facilities such as ftrace. -.SH SEE ALSO -.BR proc (5) |