NAME

       syscount.bt - Count system calls. Uses bpftrace/eBPF.

SYNOPSIS

       syscount.bt

DESCRIPTION

       This  counts  system  calls (syscalls), printing a summary of the top ten syscall IDs, and
       the top ten process names making syscalls. This can  be  helpful  for  characterizing  the
       kernel   and   resource   workload,  and  finding  applications  who  are  using  syscalls
       inefficiently.

       This works by using the tracepoint:raw_syscalls:sys_enter tracepoint.

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

REQUIREMENTS

       CONFIG_BPF and bpftrace.

EXAMPLES

       Count all VFS calls until Ctrl-C is hit:
              # syscount.bt

OUTPUT

       Top 10 syscalls IDs:
              This shows the syscall ID number (in @syscall[])  followed  by  a  count  for  this
              syscall during tracing. To see the syscall name for that ID, you can use "ausyscall
              --dump", or the bcc version of this tool that does translations.

       Top 10 processes:
              This shows the process name (in @process[]) followed by a count of syscalls  during
              tracing.

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 microbenchmark loop of 4 million calls to geteuid(), slows it down
       by 2.4x. However, this represents tracing a workload that has a syscall  rate  of  over  4
       million  syscalls  per  second  per  CPU,  which should not be typical (in one large cloud
       production environment, rates of between 10k and 50k are typical,  where  the  application
       overhead is expected to be closer to 1%).

       For comparison, strace(1) in its current ptrace-based implementation (which it has had for
       decades) runs the same geteuid() workload 102x slower (that's one hundred  and  two  times
       slower).

SOURCE

       This is from bpftrace.

              https://github.com/iovisor/bpftrace

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

       This is a bpftrace version of the bcc tool of the same name.   The  bcc  version  provides
       different command line options, and translates the syscall IDs to their syscall names.

              https://github.com/iovisor/bcc

OS

       Linux

STABILITY

       Unstable - in development.

AUTHOR

       Brendan Gregg

SEE ALSO

       strace(1)