pmctl Command

Purpose

Starts, resets, or stops generating Performance Monitor events.

Syntax

pmctl [ { [ -E [ mode ] ] [ -f interval ] {[ -y command ]} } | [ -h ] | [ -r ] | [ -S ] ] [ -s ] [ { -a -y command [ -f interval ] }]

Description

The pmctl command starts, stops, or resets the generation of Performance Monitor events in the PMAPI subsystem to support manual offline mode with the tprof -E command. It also reports the current status of the PMAPI subsystem.

Flags

Item Description
-a Turns on large page analysis.
-E [ mode ] Enables event-based profiling. You can specify one of the following modes:
PM_event
Specifies the hardware event to profile. If no mode is specified for the -E flag, the default event is processor cycles (PM_CYC).
EMULATION
Enables the emulation profiling mode.
ALIGNMENT
Enables the alignment profiling mode.
ISLBMISS
Enables the Instruction Segment Lookaside Buffer miss profiling mode.
DSLBMISS
Enables the Data Segment Lookaside Buffer miss profiling mode.
-f interval Specifies the sampling interval to use.
  • For processor cycle, EMULATION, ALIGNMENT, ISLBMISS, and DSLBMISS events, specify 1 to 500 milliseconds (default = 10).
  • For other Performance Monitor events, specify 10000 up to MAXINT occurrences (default = 10000).
If you use the -f flag with the -y flag, specify 1 up to MAXINT occurrences for other Performance Monitor events (default = 10000).
-h Prints man page information.
-r Releases and resets the PMAPI subsystem.
-S Stops generating Performance Monitor events.
-s Prints the current status of the PMAPI subsystem.
-y command Turns on the event-based profiling only for the specified command and its descendents.

Security

Attention RBAC users and Trusted AIX® users: This command can perform privileged operations. Only privileged users can run privileged operations. For more information about authorizations and privileges, see Privileged Command Database in Security. For a list of privileges and the authorizations associated with this command, see the lssecattr command or the getcmdattr subcommand.

Examples

  1. To stop generating Performance Monitoring events, enter the following command:
    pmctl –S
  2. To reset generating Performance Monitoring events, enter the following command:
    pmctl –r
  3. To report the current status of the PMAPI subsystem, enter the following command:
    pmctl –s
  4. To start generating Performance Monitoring events, enter the following command:
    pmctl –E
  5. To start generating Performance Monitoring events only for the specified workload command and its descendents, enter the following command:
    pmctl –E –y workload
  6. To support the tprof -E command in manual offline mode, enter the following command:
    trace -adf -o mydata.trc
    trcon
    pmctl –E 
    sleep 10; trcstop
    gensyms > mydata.syms
    tprof –suker mydata
  7. To support the tprof -E command in manual offline mode profiling for the specified workload command and its descendents, enter the following command:
    trace -adf -o mydata.trc
    trcon
    pmctl –E –y workload
    trcstop
    gensyms > mydata.syms
    tprof –suker mydata