NAME

       syscount - Summarize syscall counts and latencies.

SYNOPSIS

       syscount  [-h] [-p PID] [-t TID] [-c PPID] [-i INTERVAL] [-d DURATION] [-T TOP] [-x] [-e ERRNO] [-L] [-m]
       [-P] [-l] [--syscall SYSCALL]

DESCRIPTION

       This tool traces syscall entry and exit tracepoints and summarizes either the number of syscalls of  each
       type,  or  the  number  of  syscalls  per process. It can also collect latency (invocation time) for each
       syscall or each process.

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

REQUIREMENTS

       CONFIG_BPF and bcc. Linux 4.7+ is required to attach a BPF program to  the  raw_syscalls:sys_{enter,exit}
       tracepoints, used by this tool.

OPTIONS

       -h     Print usage message.

       -p PID Trace only this process.

       -t TID Trace only this thread.

       -c PPID
              Trace only child of this pid.

       -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 syscalls (i.e., the return value from the syscall was < 0).

       -e ERRNO
              Trace only syscalls 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 syscall.

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

       --syscall SYSCALL
              Trace this syscall only (use option -l to get all recognized syscalls).

EXAMPLES

       Summarize all syscalls by syscall:
              # syscount

       Summarize all syscalls by process:
              # syscount -P

       Summarize only failed syscalls:
              # syscount -x

       Summarize only syscalls that failed with EPERM:
              # syscount -e EPERM

       Trace PID 181 only:
              # syscount -p 181

       Summarize syscalls counts and latencies:
              # syscount -L

FIELDS

       PID    Process ID

       COMM   Process name

       SYSCALL
              Syscall name, or "[unknown: nnn]" for syscalls that aren't recognized

       COUNT  The number of events

       TIME   The total 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
       syscalls  per second. For higher rates, the overhead may become considerable. For example, tracing a loop
       of 4 million calls to geteuid(), slows it down by 1.85x when tracing only syscall counts,  and  slows  it
       down  by  more than 5x when tracing syscall counts and latencies. However, this represents a rate of >3.5
       million syscalls per second, which should not be typical.

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

       Sasha Goldshtein, Rocky Xing

SEE ALSO

       funccount(8), ucalls(8), argdist(8), trace(8), funclatency(8)