syscount(8)

NAME
syscount - Summarize syscall counts and latencies.

SYNOPSIS
syscount [-h] [-p PID] [-i INTERVAL] [-d DURATION] [-T TOP] [-x] [-e ERRNO] [-L] [-m] [-P] [-l]

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.

-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.

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

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