Re: Strange ARC/Swap/CPU on yesterday's -CURRENT

From: Larry Rosenman <ler_at_lerctr.org>
Date: Tue, 6 Mar 2018 13:36:45 -0600
On Tue, Mar 06, 2018 at 10:16:36AM -0800, Rodney W. Grimes wrote:
> > On Tue, Mar 06, 2018 at 08:40:10AM -0800, Rodney W. Grimes wrote:
> > > > On Mon, 5 Mar 2018 14:39-0600, Larry Rosenman wrote:
> > > > 
> > > > > Upgraded to:
> > > > > 
> > > > > FreeBSD borg.lerctr.org 12.0-CURRENT FreeBSD 12.0-CURRENT #11 r330385: Sun Mar  4 12:48:52 CST 2018     root_at_borg.lerctr.org:/usr/obj/usr/src/amd64.amd64/sys/VT-LER  amd64
> > > > > +1200060 1200060
> > > > > 
> > > > > Yesterday, and I'm seeing really strange slowness, ARC use, and SWAP use and swapping.
> > > > > 
> > > > > See http://www.lerctr.org/~ler/FreeBSD/Swapuse.png
> > > > 
> > > > I see these symptoms on stable/11. One of my servers has 32 GiB of 
> > > > RAM. After a reboot all is well. ARC starts to fill up, and I still 
> > > > have more than half of the memory available for user processes.
> > > > 
> > > > After running the periodic jobs at night, the amount of wired memory 
> > > > goes sky high. /etc/periodic/weekly/310.locate is a particular nasty 
> > > > one.
> > > 
> > > I would like to find out if this is the same person I have
> > > reporting this problem from another source, or if this is
> > > a confirmation of a bug I was helping someone else with.
> > > 
> > > Have you been in contact with Michael Dexter about this
> > > issue, or any other forum/mailing list/etc?  
> > Just IRC/Slack, with no response.
> > > 
> > > If not then we have at least 2 reports of this unbound
> > > wired memory growth, if so hopefully someone here can
> > > take you further in the debug than we have been able
> > > to get.
> > What can I provide?  The system is still in this state as the full backup is slow.
> 
> One place to look is to see if this is the recently fixed:
> https://bugs.freebsd.org/bugzilla/show_bug.cgi?id=222288
> g_bio leak.
> 
> vmstat -z | egrep 'ITEM|g_bio|UMA'
> 
> would be a good first look
> 
borg.lerctr.org /home/ler $ vmstat -z | egrep 'ITEM|g_bio|UMA'
ITEM                   SIZE  LIMIT     USED     FREE      REQ FAIL SLEEP
UMA Kegs:               280,      0,     346,       5,     560,   0,   0
UMA Zones:             1928,      0,     363,       1,     577,   0,   0
UMA Slabs:              112,      0,25384098,  977762,102033225,   0,   0
UMA Hash:               256,      0,      59,      16,     105,   0,   0
g_bio:                  384,      0,      33,    1627,542482056,   0,   0
borg.lerctr.org /home/ler $
> > > > Limiting the ARC to, say, 16 GiB, has no effect of the high amount of 
> > > > wired memory. After a few more days, the kernel consumes virtually all 
> > > > memory, forcing processes in and out of the swap device.
> > > 
> > > Our experience as well.
> > > 
> > > ...
> > > 
> > > Thanks,
> > > Rod Grimes                                                 rgrimes_at_freebsd.org
> > Larry Rosenman                     http://www.lerctr.org/~ler
> 
> -- 
> Rod Grimes                                                 rgrimes_at_freebsd.org

-- 
Larry Rosenman                     http://www.lerctr.org/~ler
Phone: +1 214-642-9640                 E-Mail: ler_at_lerctr.org
US Mail: 5708 Sabbia Drive, Round Rock, TX 78665-2106

Received on Tue Mar 06 2018 - 18:36:50 UTC

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