On Feb 8, 2012, at 7:43 PM, Artem Belevich wrote: > On Wed, Feb 8, 2012 at 4:28 PM, Jeremy Chadwick > <free...@jdc.parodius.com> wrote: >> On Thu, Feb 09, 2012 at 01:11:36AM +0100, Miroslav Lachman wrote: > ... >>> ARC Size: >>> Current Size: 1769 MB (arcsize) >>> Target Size (Adaptive): 512 MB (c) >>> Min Size (Hard Limit): 512 MB (zfs_arc_min) >>> Max Size (Hard Limit): 3584 MB (zfs_arc_max) >>> >>> The target size is going down to the min size and after few more >>> days, the system is so slow, that I must reboot the machine. Then it >>> is running fine for about 107 days and then it all repeat again. >>> >>> You can see more on MRTG graphs >>> http://freebsd.quip.cz/ext/2012/2012-02-08-kiwi-mrtg-12-15/ >>> You can see links to other useful informations on top of the page >>> (arc_summary, top, dmesg, fs usage, loader.conf) >>> >>> There you can see nightly backups (higher CPU load started at >>> 01:13), otherwise the machine is idle. >>> >>> It coresponds with ARC target size lowering in last 5 days >>> http://freebsd.quip.cz/ext/2012/2012-02-08-kiwi-mrtg-12-15/local_zfs_arcstats_size.html >>> >>> And with ARC metadata cache overflowing the limit in last 5 days >>> http://freebsd.quip.cz/ext/2012/2012-02-08-kiwi-mrtg-12-15/local_zfs_vfs_meta.html >>> >>> I don't know what's going on and I don't know if it is something >>> know / fixed in newer releases. We are running a few more ZFS >>> systems on 8.2 without this issue. But those systems are in >>> different roles. >> >> This sounds like the... damn, what is it called... some kind of internal >> "counter" or "ticks" thing within the ZFS code that was discovered to >> only begin happening after a certain period of time (which correlated to >> some number of days, possibly 107). I'm sorry that I can't be more >> specific, but it's been discussed heavily on the lists in the past, and >> fixes for all of that were committed to RELENG_8. I wish I could >> remember the name of the function or macro or variable name it pertained >> to, something like LTHAW or TLOCK or something like that. I would say >> "I don't know why I can't remember", but I do know why I can't remember: >> because I gave up trying to track all of these problems. >> >> Does someone else remember this issue? CC'ing Martin who might remember >> for certain. > > It's LBOLT. :-) > > And there was more than one related integer overflow. One of them > manifested itself as L2ARC feeding thread hogging CPU time after about > a month of uptime. Another one caused issue with ARC reclaim after 107 > days. See more details in this thread: > > http://lists.freebsd.org/pipermail/freebsd-fs/2011-May/011584.html
This would be an excellent piece of information to have on one of the ZFS wiki pages. The 107 day issue exists post-8.2, correct? Anyone on this cc: list have permissions to edit those pages? Thanks, Charles > > --Artem > _______________________________________________ > freebsd-stable@freebsd.org mailing list > http://lists.freebsd.org/mailman/listinfo/freebsd-stable > To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org" _______________________________________________ freebsd-stable@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-stable To unsubscribe, send any mail to "freebsd-stable-unsubscr...@freebsd.org"