NAME

       ppchcalls - Summarize ppc hcall counts and latencies.

SYNOPSIS

       ppchcalls [-h] [-p PID] [-t TID] [-i INTERVAL] [-d DURATION] [-T TOP] [-x] [-e ERRNO] [-L] [-m] [-P] [-l]
       [--hcall HCALL]

DESCRIPTION

       This  tool traces hcall entry and exit raw tracepoints and summarizes either the number of hcalls of each
       type, or the number of hcalls per process. It can also collect min, max  and  average  latency  for  each
       hcall or each process.

       Since this uses BPF, only the root user can use this tool.

REQUIREMENTS

       CONFIG_BPF  and bcc. Linux 4.17+ is required to attach a BPF program to the raw_hcalls:hcall_{enter,exit}
       tracepoints, used by this tool.

OPTIONS

       -h     Print usage message.

       -p PID Trace only this process.

       -t TID Trace only this thread.

       -i INTERVAL
              Print the summary at the specified interval (in seconds).

       -d DURATION
              Total duration of trace (in seconds).

       -T TOP Print only this many entries. Default: 10.

       -x     Trace only failed hcalls (i.e., the return value from the hcall was < 0).

       -e ERRNO
              Trace only hcalls that failed with that error (e.g. -e EPERM or -e 1).

       -m     Display times in milliseconds. Default: microseconds.

       -P     Summarize by process and not by hcall.

       -l     List the hcalls recognized by the tool (hard-coded list). Hcalls beyond this list  will  still  be
              displayed, as "[unknown: nnn]" where nnn is the hcall number.

       --hcall HCALL
              Trace this hcall only (use option -l to get all recognized hcalls).

EXAMPLES

       Summarize all hcalls by hcall:
              # ppchcalls

       Summarize all hcalls by process:
              # ppchcalls -P

       Summarize only failed hcalls:
              # ppchcalls -x

       Summarize only hcalls that failed with EPERM:
              # ppchcalls -e EPERM

       Trace PID 181 only:
              # ppchcalls -p 181

       Summarize hcalls counts and latencies:
              # ppchcalls -L

FIELDS

       PID    Process ID

       COMM   Process name

       HCALL  Hcall name, or "[unknown: nnn]" for hcalls that aren't recognized

       COUNT  The number of events

       MIN    The minimum elapsed time (in us or ms)

       MAX    The maximum elapsed time (in us or ms)

       AVG    The average elapsed time (in us or ms)

OVERHEAD

       For  most  applications,  the  overhead  should  be manageable if they perform 1000's or even 10,000's of
       hcalls per second. For higher rates, the overhead may become considerable.

SOURCE

       This is from bcc.

              https://github.com/iovisor/bcc

       Also look in the bcc distribution for a companion _examples.txt file containing  example  usage,  output,
       and commentary for this tool.

OS

       Linux

STABILITY

       Unstable - in development.

AUTHOR

       Harsh Prateek Bora

SEE ALSO

       syscount(8)

USER COMMANDS                                      2022-10-19                                       ppchcalls(8)