Cache very slow in 6.9rc2.

Probably the btrfs performance regression noted in the 5.10 kernel, which was recently fixed in 5.10.8. https://phoronix.com/scan.php?page=news_item&px=Linux-5.10.8-Released

Cache pool not independent with array, but I haven't ues cache pool longtime due to its performance issue. So I really don't khow difference Unraid version cache pool behaviour.

 

Why don't simple pause parity operation then check back any performance change.

Edited February 28, 2021 by Vr2Io

3 hours ago, Vr2Io said:

Cache pool not independent with array, but I haven't ues cache pool longtime due to its performance issue. So I really don't khow difference Unraid version cache pool behaviour.

 

Why don't simple pause parity operation then check back any performance change.

 

Thanks. The link explains it well. Maybe it will be solved in the release of Unraid 6.9.

 

 

I checked with and without Parity check running, no significant difference. Also checked with 90-100% load on the cpu`s, almost no difference. The biggest difference is inside/outside user path. About 500 vs. 1200-1500 MB/s. In Raid 10 nvme should do 5000 MB/s (outside user path).

Edited February 28, 2021 by frodr

I have seen posts suggesting  that the fuse implementation used to support unRaid User Shares can impose throughput limits so it is likely to be the reason you are capped at the sorts of speed you quote.