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| author | Yang Yang <yang.yang19@zte.com.cn> | 2023-04-08 17:28:35 +0800 |
|---|---|---|
| committer | Andrew Morton <akpm@linux-foundation.org> | 2023-04-18 16:39:34 -0700 |
| commit | a3b2aeac9d154e5e15ddbf19de934c0c606b6acd (patch) | |
| tree | 570fca8accf783e4fee4aba32c4263a4dde7116c /Documentation/accounting | |
| parent | 29692fc92c5b6a2c7cfe6f588ef68272e3343647 (diff) | |
| download | linux-a3b2aeac9d154e5e15ddbf19de934c0c606b6acd.tar.gz linux-a3b2aeac9d154e5e15ddbf19de934c0c606b6acd.tar.bz2 linux-a3b2aeac9d154e5e15ddbf19de934c0c606b6acd.zip | |
delayacct: track delays from IRQ/SOFTIRQ
Delay accounting does not track the delay of IRQ/SOFTIRQ. While
IRQ/SOFTIRQ could have obvious impact on some workloads productivity, such
as when workloads are running on system which is busy handling network
IRQ/SOFTIRQ.
Get the delay of IRQ/SOFTIRQ could help users to reduce such delay. Such
as setting interrupt affinity or task affinity, using kernel thread for
NAPI etc. This is inspired by "sched/psi: Add PSI_IRQ to track
IRQ/SOFTIRQ pressure"[1]. Also fix some code indent problems of older
code.
And update tools/accounting/getdelays.c:
/ # ./getdelays -p 156 -di
print delayacct stats ON
printing IO accounting
PID 156
CPU count real total virtual total delay total delay average
15 15836008 16218149 275700790 18.380ms
IO count delay total delay average
0 0 0.000ms
SWAP count delay total delay average
0 0 0.000ms
RECLAIM count delay total delay average
0 0 0.000ms
THRASHING count delay total delay average
0 0 0.000ms
COMPACT count delay total delay average
0 0 0.000ms
WPCOPY count delay total delay average
36 7586118 0.211ms
IRQ count delay total delay average
42 929161 0.022ms
[1] commit 52b1364ba0b1("sched/psi: Add PSI_IRQ to track IRQ/SOFTIRQ pressure")
Link: https://lkml.kernel.org/r/202304081728353557233@zte.com.cn
Signed-off-by: Yang Yang <yang.yang29@zte.com.cn>
Cc: Jiang Xuexin <jiang.xuexin@zte.com.cn>
Cc: wangyong <wang.yong12@zte.com.cn>
Cc: junhua huang <huang.junhua@zte.com.cn>
Cc: Balbir Singh <bsingharora@gmail.com>
Cc: Ingo Molnar <mingo@redhat.com>
Cc: Jonathan Corbet <corbet@lwn.net>
Cc: Juri Lelli <juri.lelli@redhat.com>
Cc: Peter Zijlstra <a.p.zijlstra@chello.nl>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Diffstat (limited to 'Documentation/accounting')
| -rw-r--r-- | Documentation/accounting/delay-accounting.rst | 7 |
1 files changed, 5 insertions, 2 deletions
diff --git a/Documentation/accounting/delay-accounting.rst b/Documentation/accounting/delay-accounting.rst index 79f537c9f160..f61c01fc376e 100644 --- a/Documentation/accounting/delay-accounting.rst +++ b/Documentation/accounting/delay-accounting.rst @@ -16,6 +16,7 @@ d) memory reclaim e) thrashing f) direct compact g) write-protect copy +h) IRQ/SOFTIRQ and makes these statistics available to userspace through the taskstats interface. @@ -49,7 +50,7 @@ this structure. See for a description of the fields pertaining to delay accounting. It will generally be in the form of counters returning the cumulative delay seen for cpu, sync block I/O, swapin, memory reclaim, thrash page -cache, direct compact, write-protect copy etc. +cache, direct compact, write-protect copy, IRQ/SOFTIRQ etc. Taking the difference of two successive readings of a given counter (say cpu_delay_total) for a task will give the delay @@ -118,7 +119,9 @@ Get sum of delays, since system boot, for all pids with tgid 5:: 0 0 0.000ms COMPACT count delay total delay average 0 0 0.000ms - WPCOPY count delay total delay average + WPCOPY count delay total delay average + 0 0 0.000ms + IRQ count delay total delay average 0 0 0.000ms Get IO accounting for pid 1, it works only with -p:: |