NAME¶

shmsnoop - Trace System V shared memory syscalls. Uses Linux eBPF/bcc.

SYNOPSIS¶

shmsnoop [-h] [-T] [-p] [-t] [-d DURATION] [-n NAME]

DESCRIPTION¶

shmsnoop traces System V shared memory syscalls: shmget, shmat, shmdt, shmctl

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

REQUIREMENTS¶

CONFIG_BPF and bcc.

OPTIONS¶

-h

Print usage message.

-T

Include a timestamp column.

-p PID

Trace this process ID only (filtered in-kernel).

-t TID

Trace this thread ID only (filtered in-kernel).

-d DURATION

Total duration of trace in seconds.

-n NAME

Only print command lines matching this command name (regex)

EXAMPLES¶

Trace all shm* syscalls:

# shmsnoop

Trace all shm* syscalls, and include timestamps:

# shmsnoop -T

Only trace shm* syscalls where the process contains "server":

# shmsnoop -n server

FIELDS¶

TIME(s)

Time of shm syscall return, in seconds.

PID

Process ID

COMM

Process/command name.

RET

Return value of shm syscall.

ARGS

"arg: value" couples that represent given syscall arguments as described in their manpage

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¶

Jiri Olsa

SEE ALSO¶

opensnoop(1)