fcachedaemon started using %100 CPU

[Fedon Kadifeli]

What is fcachedaemon? Why is it using %100 CPU? There is no information in HP site for fcachedaemon.

Any ideas?

[Steven E. Protter]

Shalom,

ps -ef | grep fcachedaemon

Might want to kill the process and see what happens.

Nothing about this on docs.hp.com

HP-UX?

What Version?

What was the last major patch set installed?

SEP

[Fedon Kadifeli]

This a production server: rp7440.
HP-UX 11.31


# ps -ef | grep fcachedaemon
root 60 0 219 Mar 25 ? 1523:32 fcachedaemon
root 13410 22085 0 17:17:11 pts/1 0:00 grep fcachedaemon
# find / -name fcachedaemon
#

(No match on file system!?)

Lates patch set:

QPKAPPS B.11.31.1003.347a Applications Patches for HP-UX 11i v3, March 2010
QPKBASE B.11.31.1003.347a Base Quality Pack Bundle for HP-UX 11i v3, March 2010

[Don Morris_1]

fcachedaemon is unsurprisingly the daemon which handles fcache tasks. (That's fcache as in the File Cache (UFC)). vhand handles reclaiming user memory pages within the cache -- fcachedaemon handles cases like the system reclaiming the metadata affiliated with the filecache, reclaiming unused virtual address space within the file cache [files that requested large mappings and then never used them and now we need new mapping space], etc.

The kernel itself starts this daemon as part of system initialization, you can not control nor should you kill it.

As to what it is doing -- that would take much more detailed digging into your file cache internals to know for sure.

There is QXCR1001004933 where fcachedaemon took 100% of the cpu time on a single cpu vPar due to an inefficiency in its reclamation paths. This may be what you're hitting. PHKL_41005 has that fix, and since that is after the 1003 bundle, I don't expect you have it already.

The only other option I would expect would be to contact support and let them analyze your box directly or work with you to send a crash dump for analysis. This isn't the kind of thing that can be walked through in a web forum.

[Steven E. Protter]

Shalom again,

I would read the notes on PHKL_41005 and schedule and install if you think it is relevant.

It will require a reboot and as a precaution take an Ignite backup of the boot drive before you begin.

I see no reason to analyze a crash dump unless there has actually been a system crash.

SEP