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] 209