piperd in top

Dan Nelson dnelson at allantgroup.com
Wed Aug 2 17:05:45 UTC 2006

In the last episode (Aug 02), DAve said:
> Dan Nelson wrote:
> >In the last episode (Aug 01), DAve said:
> >>We are in the process of getting a good hammering of spam. I've
> >>been watching my mail gateways and they are keeping up well enough.
> >>But looking at top I am seeing a lot of processes with state of
> >>piperd.
> >
> >Piperd means the process is waiting on a read from a pipe.  You can
> >use lsof to determine what process is at the other end of the pipe
> >(run lsof, find your process, find the PIPE fd, then find the other
> >process with the same 0xXXXXXXXX value).
> Excellent, thank you. May I ask where you found that info. I looked
> but came up empty. I'd like to know the meanings of some other states
> not mentioned in the man pages. Such as nanslp, *GIANT, kqread, etc.

The only place wait states are documented is the source, basically. 
There are many hundreds of them.  States with an asterisk are mutexes
To find the code related to piperd:

find /usr/src/sys -name "*.c" | xargs grep -n piperd

	Dan Nelson
	dnelson at allantgroup.com

More information about the freebsd-questions mailing list