9.10 virtualbox & memory fault

[wtfR6a]

Has anyone observed FreeNAS using more free memory on 9.10 than under 9.3?
Specifically related to Virtualbox and a Windows VM which fell over due to a lack of memory earlier today. Ive not seen this before in months of this VM running under 9.3.

Ive attached my 9.3 memory utilisation graph which shows circa 10G free, compared to 9.10 which is < 2G approximately.

Is there a way to enforce some memory being left for Virtualbox machines or other jails?

 

[DrKK]

I'd file this as a bug, because this should not have happened, I don't think. But:

Is there a way to enforce some memory being left for Virtualbox machines or other jails?

Yes, you can set an arc_max. e.g., this will set the max zfs cache usage to 110GB:

System->Tunables->Add Tunable

Variable: vfs.zfs.arc_max
Value: 110g
Type: Loader

Note that whatever you put into "Value", the "g" for GB is lower case (I don't know if that's still important...). This will mean that no more than 110GB of memory (or whatever you select) will get wired to the ARC.

 

[DrKK]

And, by the way, a new "loader" will not effect until a reboot. So you will have to reboot the box. ***DO NOT*** mis-spell or mis-type the loader information, because you could hang up your box.