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1perf-sched(1)
2=============
3
4NAME
5----
6perf-sched - Tool to trace/measure scheduler properties (latencies)
7
8SYNOPSIS
9--------
10[verse]
11'perf sched' {record|latency|map|replay|script|timehist}
12
13DESCRIPTION
14-----------
15There are several variants of 'perf sched':
16
17 'perf sched record <command>' to record the scheduling events
18 of an arbitrary workload.
19
20 'perf sched latency' to report the per task scheduling latencies
21 and other scheduling properties of the workload.
22
23 'perf sched script' to see a detailed trace of the workload that
24 was recorded (aliased to 'perf script' for now).
25
26 'perf sched replay' to simulate the workload that was recorded
27 via perf sched record. (this is done by starting up mockup threads
28 that mimic the workload based on the events in the trace. These
29 threads can then replay the timings (CPU runtime and sleep patterns)
30 of the workload as it occurred when it was recorded - and can repeat
31 it a number of times, measuring its performance.)
32
33 'perf sched map' to print a textual context-switching outline of
34 workload captured via perf sched record. Columns stand for
35 individual CPUs, and the two-letter shortcuts stand for tasks that
36 are running on a CPU. A '*' denotes the CPU that had the event, and
37 a dot signals an idle CPU.
38
39 'perf sched timehist' provides an analysis of scheduling events.
40
41 Example usage:
42 perf sched record -- sleep 1
43 perf sched timehist
44
45 By default it shows the individual schedule events, including the wait
46 time (time between sched-out and next sched-in events for the task), the
47 task scheduling delay (time between wakeup and actually running) and run
48 time for the task:
49
50 time cpu task name wait time sch delay run time
51 [tid/pid] (msec) (msec) (msec)
52 -------------- ------ -------------------- --------- --------- ---------
53 79371.874569 [0011] gcc[31949] 0.014 0.000 1.148
54 79371.874591 [0010] gcc[31951] 0.000 0.000 0.024
55 79371.874603 [0010] migration/10[59] 3.350 0.004 0.011
56 79371.874604 [0011] <idle> 1.148 0.000 0.035
57 79371.874723 [0005] <idle> 0.016 0.000 1.383
58 79371.874746 [0005] gcc[31949] 0.153 0.078 0.022
59 ...
60
61 Times are in msec.usec.
62
63OPTIONS
64-------
65-i::
66--input=<file>::
67 Input file name. (default: perf.data unless stdin is a fifo)
68
69-v::
70--verbose::
71 Be more verbose. (show symbol address, etc)
72
73-D::
74--dump-raw-trace=::
75 Display verbose dump of the sched data.
76
77-f::
78--force::
79 Don't complain, do it.
80
81OPTIONS for 'perf sched map'
82----------------------------
83
84--compact::
85 Show only CPUs with activity. Helps visualizing on high core
86 count systems.
87
88--cpus::
89 Show just entries with activities for the given CPUs.
90
91--color-cpus::
92 Highlight the given cpus.
93
94--color-pids::
95 Highlight the given pids.
96
97OPTIONS for 'perf sched timehist'
98---------------------------------
99-k::
100--vmlinux=<file>::
101 vmlinux pathname
102
103--kallsyms=<file>::
104 kallsyms pathname
105
106-g::
107--call-graph::
108 Display call chains if present (default on).
109
110--max-stack::
111 Maximum number of functions to display in backtrace, default 5.
112
113-C=::
114--cpu=::
115 Only show events for the given CPU(s) (comma separated list).
116
117-p=::
118--pid=::
119 Only show events for given process ID (comma separated list).
120
121-t=::
122--tid=::
123 Only show events for given thread ID (comma separated list).
124
125-s::
126--summary::
127 Show only a summary of scheduling by thread with min, max, and average
128 run times (in sec) and relative stddev.
129
130-S::
131--with-summary::
132 Show all scheduling events followed by a summary by thread with min,
133 max, and average run times (in sec) and relative stddev.
134
135--symfs=<directory>::
136 Look for files with symbols relative to this directory.
137
138-V::
139--cpu-visual::
140 Show visual aid for sched switches by CPU: 'i' marks idle time,
141 's' are scheduler events.
142
143-w::
144--wakeups::
145 Show wakeup events.
146
147-M::
148--migrations::
149 Show migration events.
150
151-n::
152--next::
153 Show next task.
154
155-I::
156--idle-hist::
157 Show idle-related events only.
158
159--time::
160 Only analyze samples within given time window: <start>,<stop>. Times
161 have the format seconds.microseconds. If start is not given (i.e., time
162 string is ',x.y') then analysis starts at the beginning of the file. If
163 stop time is not given (i.e, time string is 'x.y,') then analysis goes
164 to end of file.
165
166--state::
167 Show task state when it switched out.
168
169SEE ALSO
170--------
171linkperf:perf-record[1]
1perf-sched(1)
2=============
3
4NAME
5----
6perf-sched - Tool to trace/measure scheduler properties (latencies)
7
8SYNOPSIS
9--------
10[verse]
11'perf sched' {record|latency|map|replay|script|timehist}
12
13DESCRIPTION
14-----------
15There are several variants of 'perf sched':
16
17 'perf sched record <command>' to record the scheduling events
18 of an arbitrary workload.
19
20 'perf sched latency' to report the per task scheduling latencies
21 and other scheduling properties of the workload.
22
23 'perf sched script' to see a detailed trace of the workload that
24 was recorded (aliased to 'perf script' for now).
25
26 'perf sched replay' to simulate the workload that was recorded
27 via perf sched record. (this is done by starting up mockup threads
28 that mimic the workload based on the events in the trace. These
29 threads can then replay the timings (CPU runtime and sleep patterns)
30 of the workload as it occurred when it was recorded - and can repeat
31 it a number of times, measuring its performance.)
32
33 'perf sched map' to print a textual context-switching outline of
34 workload captured via perf sched record. Columns stand for
35 individual CPUs, and the two-letter shortcuts stand for tasks that
36 are running on a CPU. A '*' denotes the CPU that had the event, and
37 a dot signals an idle CPU.
38
39 'perf sched timehist' provides an analysis of scheduling events.
40
41 Example usage:
42 perf sched record -- sleep 1
43 perf sched timehist
44
45 By default it shows the individual schedule events, including the wait
46 time (time between sched-out and next sched-in events for the task), the
47 task scheduling delay (time between wakeup and actually running) and run
48 time for the task:
49
50 time cpu task name wait time sch delay run time
51 [tid/pid] (msec) (msec) (msec)
52 -------------- ------ -------------------- --------- --------- ---------
53 79371.874569 [0011] gcc[31949] 0.014 0.000 1.148
54 79371.874591 [0010] gcc[31951] 0.000 0.000 0.024
55 79371.874603 [0010] migration/10[59] 3.350 0.004 0.011
56 79371.874604 [0011] <idle> 1.148 0.000 0.035
57 79371.874723 [0005] <idle> 0.016 0.000 1.383
58 79371.874746 [0005] gcc[31949] 0.153 0.078 0.022
59 ...
60
61 Times are in msec.usec.
62
63OPTIONS
64-------
65-i::
66--input=<file>::
67 Input file name. (default: perf.data unless stdin is a fifo)
68
69-v::
70--verbose::
71 Be more verbose. (show symbol address, etc)
72
73-D::
74--dump-raw-trace=::
75 Display verbose dump of the sched data.
76
77-f::
78--force::
79 Don't complain, do it.
80
81OPTIONS for 'perf sched map'
82----------------------------
83
84--compact::
85 Show only CPUs with activity. Helps visualizing on high core
86 count systems.
87
88--cpus::
89 Show just entries with activities for the given CPUs.
90
91--color-cpus::
92 Highlight the given cpus.
93
94--color-pids::
95 Highlight the given pids.
96
97OPTIONS for 'perf sched timehist'
98---------------------------------
99-k::
100--vmlinux=<file>::
101 vmlinux pathname
102
103--kallsyms=<file>::
104 kallsyms pathname
105
106-g::
107--call-graph::
108 Display call chains if present (default on).
109
110--max-stack::
111 Maximum number of functions to display in backtrace, default 5.
112
113-p=::
114--pid=::
115 Only show events for given process ID (comma separated list).
116
117-t=::
118--tid=::
119 Only show events for given thread ID (comma separated list).
120
121-s::
122--summary::
123 Show only a summary of scheduling by thread with min, max, and average
124 run times (in sec) and relative stddev.
125
126-S::
127--with-summary::
128 Show all scheduling events followed by a summary by thread with min,
129 max, and average run times (in sec) and relative stddev.
130
131--symfs=<directory>::
132 Look for files with symbols relative to this directory.
133
134-V::
135--cpu-visual::
136 Show visual aid for sched switches by CPU: 'i' marks idle time,
137 's' are scheduler events.
138
139-w::
140--wakeups::
141 Show wakeup events.
142
143-M::
144--migrations::
145 Show migration events.
146
147-n::
148--next::
149 Show next task.
150
151-I::
152--idle-hist::
153 Show idle-related events only.
154
155--time::
156 Only analyze samples within given time window: <start>,<stop>. Times
157 have the format seconds.microseconds. If start is not given (i.e., time
158 string is ',x.y') then analysis starts at the beginning of the file. If
159 stop time is not given (i.e, time string is 'x.y,') then analysis goes
160 to end of file.
161
162--state::
163 Show task state when it switched out.
164
165SEE ALSO
166--------
167linkperf:perf-record[1]