Date: Tue, 14 Jan 2014 22:29:42 +0200 From: Andriy Gapon <avg@FreeBSD.org> To: Vladimir Sharun <atz@ukr.net>, Current FreeBSD <freebsd-current@FreeBSD.org> Subject: Re: ARC "pressured out", how to control/stabilize ? (reformatted to text/plain) Message-ID: <52D59E36.9040405@FreeBSD.org> In-Reply-To: <1389676958.516993176.oq4lbgg7@frv45.ukr.net> References: <1388839805.123581691.q97ijp8l@frv45.ukr.net> <52C93E4D.1050100@FreeBSD.org> <1389005433.815055146.2dcjke36@frv45.ukr.net> <52CA9963.1050507@FreeBSD.org> <1389676958.516993176.oq4lbgg7@frv45.ukr.net>
next in thread | previous in thread | raw e-mail | index | archive | help
on 14/01/2014 07:27 Vladimir Sharun said the following: > Dear Andriy and FreeBSD community, > >> I am not sure if the buffers are leaked somehow or if they are actually in use. >> It's one of the very few places where data buffers are allocated without >> charging ARC. In all other places it's quite easy to match allocations and >> deallocations. But in L2ARC it is not obvious that all buffers get freed or >> when that happens. > > After one week under load I think we figure out the cause: it's L2ARC. > Here's the top's header for 7d17h of the runtime: > > last pid: 46409; load averages: 0.37, 0.62, 0.70 up 7+17:14:01 07:24:10 > 173 processes: 1 running, 171 sleeping, 1 zombie > CPU: 2.0% user, 0.0% nice, 3.5% system, 0.4% interrupt, 94.2% idle > Mem: 8714M Active, 14G Inact, 96G Wired, 1929M Cache, 3309M Buf, 3542M Free > ARC: 85G Total, 2558M MFU, 77G MRU, 28M Anon, 1446M Header, 4802M Other > > ARC related tunables: > > vm.kmem_size="110G" > vfs.zfs.arc_max="90G" > vfs.zfs.arc_min="42G" > > For more than 7 days of hard runtime the picture clearly shows: > Wired minus ARC = 11..12Gb, ARC grow and shrinks in 80-87Gb range and the > system runs just fine. > > So what shall we do with L2ARC leakage ? Could you please try this patch http://cr.illumos.org/~webrev/skiselkov/3995/illumos-gate.patch ? -- Andriy Gapon
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?52D59E36.9040405>