Lowering arc limit with ZFS when low on ram?

zack3334

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Dec 22, 2020
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I have a system using zfs it only has 64 GB of memory in the unit with 241TB of storage, I have 3 windows vm's using 8gb each arc hit ratio at 84% .Proxmox shows a total of 48.11 GiB of 62.57 GiB used (76.89%)

my vm's become extremely sluggish during a resilver so much so that we can't log in . would lowering the arc limit to the following help me at all? and if so what kind of hit on performance can I expect to see?

Please, check my math on this but I believe with 64gb of ram in bytes would be 65,536,000,000

we want to make the max 40% And min 14%

40%: 26214400000

14%: 9175040000
 
I don't think that reducing file caching will improve a resilver: the disk is busy and you are making it more busy when less cache fits in memory.
Have a look here (and the posts above it) about changing the ARC limits.