1 perf-sched(1)
2 =============
3
4 NAME
5 ----
6 perf-sched - Tool to trace/measure scheduler p
7
8 SYNOPSIS
9 --------
10 [verse]
11 'perf sched' {record|latency|map|replay|script
12
13 DESCRIPTION
14 -----------
15 There are several variants of 'perf sched':
16
17 'perf sched record <command>' to record the
18 of an arbitrary workload.
19
20 'perf sched latency' to report the per task
21 and other scheduling properties of the workl
22
23 Example usage:
24 perf sched record -- sleep 1
25 perf sched latency
26
27 --------------------------------------------
28 Task | Runtime ms | Cou
29 --------------------------------------------
30 perf:(2) | 2.804 ms |
31 NetworkManager:1343 | 0.372 ms |
32 kworker/1:2-xfs:4649 | 0.012 ms |
33 kworker/3:1-xfs:388 | 0.011 ms |
34 sleep:147736 | 0.938 ms |
35
36 It shows Runtime(time that a task spent actu
37 Count(number of times a delay was calculated
38 task was ready to run but was kept waiting).
39
40 Tasks with the same command name are merged
41 given within (), However if -p option is use
42
43 'perf sched script' to see a detailed trace
44 was recorded (aliased to 'perf script' for
45
46 'perf sched replay' to simulate the workload
47 via perf sched record. (this is done by star
48 that mimic the workload based on the events
49 threads can then replay the timings (CPU run
50 of the workload as it occurred when it was r
51 it a number of times, measuring its performa
52
53 'perf sched map' to print a textual context-
54 workload captured via perf sched record. Co
55 individual CPUs, and the two-letter shortcut
56 are running on a CPU. A '*' denotes the CPU
57 a dot signals an idle CPU.
58
59 'perf sched timehist' provides an analysis o
60
61 Example usage:
62 perf sched record -- sleep 1
63 perf sched timehist
64
65 By default it shows the individual schedule
66 time (time between sched-out and next sched
67 task scheduling delay (time between runnabl
68 run time for the task:
69
70 time cpu task name
71 [tid/pid]
72 -------------- ------ -----------------
73 79371.874569 [0011] gcc[31949]
74 79371.874591 [0010] gcc[31951]
75 79371.874603 [0010] migration/10[59]
76 79371.874604 [0011] <idle>
77 79371.874723 [0005] <idle>
78 79371.874746 [0005] gcc[31949]
79 ...
80
81 Times are in msec.usec.
82
83 OPTIONS
84 -------
85 -i::
86 --input=<file>::
87 Input file name. (default: perf.data u
88
89 -v::
90 --verbose::
91 Be more verbose. (show symbol address,
92
93 -D::
94 --dump-raw-trace=::
95 Display verbose dump of the sched data
96
97 -f::
98 --force::
99 Don't complain, do it.
100
101 OPTIONS for 'perf sched latency'
102 -------------------------------
103
104 -C::
105 --CPU <n>::
106 CPU to profile on.
107
108 -p::
109 --pids::
110 latency stats per pid instead of per c
111
112 -s::
113 --sort <key[,key2...]>::
114 sort by key(s): runtime, switch, avg,
115 by default it's sorted by "avg ,max ,s
116
117 OPTIONS for 'perf sched map'
118 ----------------------------
119
120 --compact::
121 Show only CPUs with activity. Helps vi
122 count systems.
123
124 --cpus::
125 Show just entries with activities for
126
127 --color-cpus::
128 Highlight the given cpus.
129
130 --color-pids::
131 Highlight the given pids.
132
133 --task-name <task>::
134 Map output only for the given task nam
135 task names with a comma (without white
136 time is printed and is represented by
137 task name(s).
138 ('-' indicates other tasks while '.' i
139
140 --fuzzy-name::
141 Given task name(s) can be partially ma
142
143 OPTIONS for 'perf sched timehist'
144 ---------------------------------
145 -k::
146 --vmlinux=<file>::
147 vmlinux pathname
148
149 --kallsyms=<file>::
150 kallsyms pathname
151
152 -g::
153 --call-graph::
154 Display call chains if present (defaul
155
156 --max-stack::
157 Maximum number of functions to display
158
159 -C=::
160 --cpu=::
161 Only show events for the given CPU(s)
162
163 -p=::
164 --pid=::
165 Only show events for given process ID
166
167 -t=::
168 --tid=::
169 Only show events for given thread ID (
170
171 -s::
172 --summary::
173 Show only a summary of scheduling by threa
174 run times (in sec) and relative stddev.
175
176 -S::
177 --with-summary::
178 Show all scheduling events followed by a s
179 max, and average run times (in sec) and re
180
181 --symfs=<directory>::
182 Look for files with symbols relative to th
183
184 -V::
185 --cpu-visual::
186 Show visual aid for sched switches by
187 's' are scheduler events.
188
189 -w::
190 --wakeups::
191 Show wakeup events.
192
193 -M::
194 --migrations::
195 Show migration events.
196
197 -n::
198 --next::
199 Show next task.
200
201 -I::
202 --idle-hist::
203 Show idle-related events only.
204
205 --time::
206 Only analyze samples within given time
207 have the format seconds.microseconds.
208 string is ',x.y') then analysis starts
209 stop time is not given (i.e, time stri
210 to end of file.
211
212 --state::
213 Show task state when it switched out.
214
215 --show-prio::
216 Show task priority.
217
218 --prio::
219 Only show events for given task priori
220 provided as a comma-separated list wit
221 priorities are specified with -: 120-1
222 provided: 0,120-129.
223
224 OPTIONS for 'perf sched replay'
225 ------------------------------
226
227 -r::
228 --repeat <n>::
229 repeat the workload n times (0: infini
230
231 SEE ALSO
232 --------
233 linkperf:perf-record[1]
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