Fadvise memory leak on 8.3-RELEASE

phil.davis

I was looking for things that used memory (related to http://forum.pfsense.org/index.php/topic,59237.0.html) and found this little issue:

vmstat -m | grep fadvise
      fadvise 164447  5139K       -   164447  32

Apparently there is a memory leak in the posix_fadvise function in FreeBSD 8.3-RELEASE which has been fixed in the 8-STABLE mainline. My nanoBSD system has leaked 5MB in a couple of days of uptime. That would become significant when a 256MB nanoBSD system is up for a month. After rebooting, the fadvise usage starts back at 1K and slowly increases.
FreeBSD 8.3 release notes have references to posix_fadvise - http://www.freebsd.org/releases/8.3R/relnotes-detailed.html
This FreeBSD forum thread has some symptoms etc - http://forums.freebsd.org/showthread.php?p=192718
and this thread indicates that RRDtool uses posix_fadvise, running up kernel memory leaks - http://oss.oetiker.ch/rrdtool/forum.en.html#nabble-td7580539
and the fix (claimed) is here - http://svnweb.freebsd.org/base?view=revision&revision=234661
Can someone see if this is a good fix, is worth doing and is possible to patch into the pfSense FreeBSD 8.3?

jimp

If it really is leaking, sure. Open up a ticket on redmine and we can look into it.

phil.davis

Ticket #2835 http://redmine.pfsense.org/issues/2835