| .TH pidpersec 8 "2015-08-18" "USER COMMANDS" |
| .SH NAME |
| pidpersec \- Count new processes (via fork()). Uses Linux eBPF/bcc. |
| .SH SYNOPSIS |
| .B pidpersec |
| .SH DESCRIPTION |
| pidpersec shows how many new processes were created each second. There |
| can be performance issues caused by many short-lived processes, which may not |
| be visible in sampling tools like top(1). pidpersec provides one way to |
| investigate this behavior. |
| |
| This works by tracing the kernel sched_fork() function using dynamic tracing, |
| and will need updating to match any changes to this function. |
| |
| Since this uses BPF, only the root user can use this tool. |
| .SH REQUIREMENTS |
| CONFIG_BPF and bcc. |
| .SH EXAMPLES |
| .TP |
| Count new processes created each second: |
| # |
| .B pidpersec |
| .SH OVERHEAD |
| This traces the kernel fork function, and maintains an in-kernel count which is |
| read asynchronously from user-space. As the rate of this is generally expected to |
| be low (<< 1000/s), the overhead is also expected to be negligible. |
| .SH SOURCE |
| This is from bcc. |
| .IP |
| https://github.com/iovisor/bcc |
| .PP |
| Also look in the bcc distribution for a companion _examples.txt file containing |
| example usage, output, and commentary for this tool. |
| .SH OS |
| Linux |
| .SH STABILITY |
| Unstable - in development. |
| .SH AUTHOR |
| Brendan Gregg |
| .SH SEE ALSO |
| top(1) |
