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

[Jeff Roberson]

On Sun, 11 Mar 2018, Matthew D. Fuller wrote:

> On Sun, Mar 11, 2018 at 10:43:58AM -1000 I heard the voice of
> Jeff Roberson, and lo! it spake thus:
>>
>> First, I would like to identify whether the wired memory is in the
>> buffer cache.  Can those of you that have a repro look at sysctl
>> vfs.bufspace and tell me if that accounts for the bulk of your wired
>> memory usage?  I'm wondering if a job ran that pulled in all of the
>> bufs from your root disk and filled up the buffer cache which
>> doesn't have a back-pressure mechanism.
>
> If by "root disk", you mean the one that isn't ZFS, that wouldn't
> touch anything here; apart from a md-backed UFS /tmp and some NFS
> mounts, everything on my system is ZFS.
>
> I believe vfs.bufspace is what shows up as "Buf" on top?  I don't
> recall it looking particularly interesting when things were madly
> swapping.  I'll uncork arc_max again for a bit and see if anything odd
> shows up in it, but it's only a dozen megs or so now.

You are right.  I forgot that it was in top and didn't notice.

What I believe I need most is for someone to bisect a few revisions to let 
me know if it was one of my two major patches.

Thanks,
Jeff

>
>
>
> -- 
> Matthew Fuller     (MF4839)   |  fullermd at over-yonder.net
> Systems/Network Administrator |  http://www.over-yonder.net/~fullermd/
>           On the Internet, nobody can hear you scream.
>