1perf-daemon(1)
  2==============
  3
  4
  5NAME
  6----
  7perf-daemon - Run record sessions on background
  8
  9
 10SYNOPSIS
 11--------
 12[verse]
 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>]
 19
 20
 21DESCRIPTION
 22-----------
 23This command allows to run simple daemon process that starts and
 24monitors configured record sessions.
 25
 26You can imagine 'perf daemon' of background process with several
 27'perf record' child tasks, like:
 28
 29  # ps axjf
 30  ...
 31       1  916507 ... perf daemon start
 32  916507  916508 ...  \_ perf record --control=fifo:control,ack -m 10M -e cycles --overwrite --switch-output -a
 33  916507  916509 ...  \_ perf record --control=fifo:control,ack -m 20M -e sched:* --overwrite --switch-output -a
 34
 35Not every 'perf record' session is suitable for running under daemon.
 36User need perf session that either produces data on query, like the
 37flight recorder sessions in above example or session that is configured
 38to produce data periodically, like with --switch-output configuration
 39for time and size.
 40
 41Each session is started with control setup (with perf record --control
 42options).
 43
 44Sessions are configured through config file, see CONFIG FILE section
 45with EXAMPLES.
 46
 47
 48OPTIONS
 49-------
 50-v::
 51--verbose::
 52	Be more verbose.
 53
 54--config=<PATH>::
 55	Config file path. If not provided, perf will check system and default
 56	locations (/etc/perfconfig, $HOME/.perfconfig).
 57
 58--base=<PATH>::
 59	Base directory path. Each daemon instance is running on top
 60	of base directory. Only one instance of server can run on
 61	top of one directory at the time.
 62
 63All generic options are available also under commands.
 64
 65
 66START COMMAND
 67-------------
 68The start command creates the daemon process.
 69
 70-f::
 71--foreground::
 72	Do not put the process in background.
 73
 74
 75STOP COMMAND
 76------------
 77The stop command stops all the session and the daemon process.
 78
 79
 80SIGNAL COMMAND
 81--------------
 82The signal command sends signal to configured sessions.
 83
 84--session::
 85	Send signal to specific session.
 86
 87
 88PING COMMAND
 89------------
 90The ping command sends control ping to configured sessions.
 91
 92--session::
 93	Send ping to specific session.
 94
 95
 96CONFIG FILE
 97-----------
 98The daemon is configured within standard perf config file by
 99following new variables:
100
101daemon.base:
102	Base path for daemon data. All sessions data are
103	stored under this path.
104
105session-<NAME>.run:
106	Defines new record session. The value is record's command
107	line without the 'record' keyword.
108
109Each perf record session is run in daemon.base/<NAME> directory.
110
111
112EXAMPLES
113--------
114Example with 2 record sessions:
115
116  # cat ~/.perfconfig
117  [daemon]
118  base=/opt/perfdata
119
120  [session-cycles]
121  run = -m 10M -e cycles --overwrite --switch-output -a
122
123  [session-sched]
124  run = -m 20M -e sched:* --overwrite --switch-output -a
125
126
127Starting the daemon:
128
129  # perf daemon start
130
131
132Check sessions:
133
134  # perf daemon
135  [603349:daemon] base: /opt/perfdata
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
138
139First line is daemon process info with configured daemon base.
140
141
142Check sessions with more info:
143
144  # perf daemon -v
145  [603349:daemon] base: /opt/perfdata
146    output:  /opt/perfdata/output
147    lock:    /opt/perfdata/lock
148    up:      1 minutes
149  [603350:cycles] perf record -m 10M -e cycles --overwrite --switch-output -a
150    base:    /opt/perfdata/session-cycles
151    output:  /opt/perfdata/session-cycles/output
152    control: /opt/perfdata/session-cycles/control
153    ack:     /opt/perfdata/session-cycles/ack
154    up:      1 minutes
155  [603351:sched] perf record -m 20M -e sched:* --overwrite --switch-output -a
156    base:    /opt/perfdata/session-sched
157    output:  /opt/perfdata/session-sched/output
158    control: /opt/perfdata/session-sched/control
159    ack:     /opt/perfdata/session-sched/ack
160    up:      1 minutes
161
162The 'base' path is daemon/session base.
163The 'lock' file is daemon's lock file guarding that no other
164daemon is running on top of the base.
165The 'output' file is perf record output for specific session.
166The 'control' and 'ack' files are perf control files.
167The 'up' number shows minutes daemon/session is running.
168
169
170Make sure control session is online:
171
172  # perf daemon ping
173  OK   cycles
174  OK   sched
175
176
177Send USR2 signal to session 'cycles' to generate perf.data file:
178
179  # perf daemon signal --session cycles
180  signal 12 sent to session 'cycles [603452]'
181
182  # tail -2  /opt/perfdata/session-cycles/output
183  [ perf record: dump data: Woken up 1 times ]
184  [ perf record: Dump perf.data.2020123017013149 ]
185
186
187Send USR2 signal to all sessions:
188
189  # perf daemon signal
190  signal 12 sent to session 'cycles [603452]'
191  signal 12 sent to session 'sched [603453]'
192
193  # tail -2  /opt/perfdata/session-cycles/output
194  [ perf record: dump data: Woken up 1 times ]
195  [ perf record: Dump perf.data.2020123017024689 ]
196  # tail -2  /opt/perfdata/session-sched/output
197  [ perf record: dump data: Woken up 1 times ]
198  [ perf record: Dump perf.data.2020123017024713 ]
199
200
201Stop daemon:
202
203  # perf daemon stop
204
205
206SEE ALSO
207--------
208linkperf:perf-record[1], linkperf:perf-config[1]