TrueNAS 12 - Ideas for increased NFS performance?

[HoneyBadger]

You da man @HoneyBadger ! Check this out.

Code:

  4  75698                 none:txg-syncing 28685MB of 65536MB used

I would say I have this pushed to the limits of what my spinning rust can do. Thanks all for the assistance. Now I just need to convince my wife that I need a whole pile of SSD's.

Just bear in mind that with the dirty_data_max pushed up this high, that's potentially 64GB of ARC data being suddenly and impolitely evicted from your RAM during a heavy write workload, which could cause more read activity against your disks, which could cause your writes to slow down, which causes the dirty data to pile up higher, and evict more usable data from ARC ... watch the potential for a vicious circle, and if your ARC hit rate drops under write pressure, pull that 64G back to a smaller value.

 

[Elliot Dierksen]

if your ARC hit rate drops under write pressure, pull that 64G back to a smaller value.

Got it, thanks! That is a pretty unlikely scenario for me since the only time I get that volume of write traffic is when I am using Vmotion to move the hosts around. I still have 23G of RAM free even with a ZFS cache size of 203.5G.