NAME

       statsnoop - Trace stat() syscalls. Uses Linux eBPF/bcc.

SYNOPSIS

       statsnoop [-h] [-t] [-x] [-p PID]

DESCRIPTION

       statsnoop  traces  the  different  stat()  syscalls,  showing  which  processes  are  attempting  to read
       information about which files. This can be useful for determining the location of config and  log  files,
       or for troubleshooting applications that are failing, especially on startup.

       This  works  by tracing various kernel sys_stat() functions using dynamic tracing, and will need updating
       to match any changes to these functions.

       This makes use of a Linux 4.5 feature (bpf_perf_event_output()); for kernels  older  than  4.5,  see  the
       version under tools/old, which uses an older mechanism.

       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: in seconds since the first event, with decimal places.

       -x     Only print failed stats.

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

EXAMPLES

       Trace all stat() syscalls:
              # statsnoop

       Trace all stat() syscalls, and include timestamps:
              # statsnoop -t

       Trace only stat() syscalls that failed:
              # statsnoop -x

       Trace PID 181 only:
              # statsnoop -p 181

FIELDS

       TIME(s)
              Time of the call, in seconds.

       PID    Process ID

       COMM   Process name

       FD     File descriptor (if success), or -1 (if failed)

       ERR    Error number (see the system's errno.h)

       PATH   Open path

OVERHEAD

       This  traces  the kernel stat function and prints output for each event. As the rate of this is generally
       expected to be low (< 1000/s), the overhead is also expected to be negligible. If you have an application
       that is calling a high rate of stat()s, then test and understand overhead before use.

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

       Brendan Gregg

SEE ALSO

       opensnoop(1)