perf/Documentation/perf-daemon.txt

1 perf-daemon(1)
7 perf-daemon - Run record sessions on background
13 'perf daemon'
14 'perf daemon' [<options>]
15 'perf daemon start'  [<options>]
16 'perf daemon stop'   [<options>]
17 'perf daemon signal' [<options>]
18 'perf daemon ping'   [<options>]
26 You can imagine 'perf daemon' of background process with several
27 'perf record' child tasks, like:
31        1  916507 ... perf daemon start
32 …916507  916508 ...  \_ perf record --control=fifo:control,ack -m 10M -e cycles --overwrite --switc…
33 …916507  916509 ...  \_ perf record --control=fifo:control,ack -m 20M -e sched:* --overwrite --swit…
35 Not every 'perf record' session is suitable for running under daemon.
36 User need perf session that either produces data on query, like the
41 Each session is started with control setup (with perf record --control
55 	Config file path. If not provided, perf will check system and default
98 The daemon is configured within standard perf config file by
109 Each perf record session is run in daemon.base/<NAME> directory.
129   # perf daemon start
134   # perf daemon
136   [603350:cycles] perf record -m 10M -e cycles --overwrite --switch-output -a
137   [603351:sched] perf record -m 20M -e sched:* --overwrite --switch-output -a
144   # perf daemon -v
149   [603350:cycles] perf record -m 10M -e cycles --overwrite --switch-output -a
155   [603351:sched] perf record -m 20M -e sched:* --overwrite --switch-output -a
165 The 'output' file is perf record output for specific session.
166 The 'control' and 'ack' files are perf control files.
172   # perf daemon ping
177 Send USR2 signal to session 'cycles' to generate perf.data file:
179   # perf daemon signal --session cycles
183   [ perf record: dump data: Woken up 1 times ]
184   [ perf record: Dump perf.data.2020123017013149 ]
189   # perf daemon signal
194   [ perf record: dump data: Woken up 1 times ]
195   [ perf record: Dump perf.data.2020123017024689 ]
197   [ perf record: dump data: Woken up 1 times ]
198   [ perf record: Dump perf.data.2020123017024713 ]
203   # perf daemon stop
208 linkperf:perf-record[1], linkperf:perf-config[1]