FreeBSD 10.1 Memory Exhaustion

[Mark Felder]

On Tue, Jul 14, 2015, at 10:10, Sean Chittenden wrote:
> I think the reason this is not seen more often is because people
> frequently
> throw limits on the arc in /boot/loader.conf:
> 
> vfs.zfs.arc_min="18G"
> vfs.zfs.arc_max="149G"
> 
> ZFS ARC *should* not require those settings, but does currently for mixed
> workloads (i.e. databases) in order to be "stable".  By setting fixed
> sizes
> on the ARC, UMA and ARC are much more cooperative in that they have their
> own memory regions to manage so this behavior is not seen as often.
> 
> To be clear, however, it should not be necessary to set parameters like
> these in /boot/loader.conf in order to obtain consistent operational
> behavior.  I'd be curious to know if someone running 10.2 BETA without
> patches is able to trigger this behavior or not.  There was work done
> that
> reported helped with this between 10.1 and now.  To what extent it
> helped,
> however, I don't have any advice yet.
> 

I was about to email "I have 12TB at home and 4GB of RAM with a very
erratic workload and never run into any issues" and then I looked at
/boot/loader.conf and saw vfs.zfs.arc_max="2G"

Now I'm too scared to turn it off... :-)