Toshiba Persistent Write Cache

[Joze Volf]

Anybody using Toshiba Enteprise drives w/ Persistent Write Cache in their ZFS pools? This should do miracles in configurations w/o separate fast SLOG devices. I am waiting for the following system to do some testing but I am very much interested in experiences by other users.

X10SDV-7TP4F
SC836BA-R920B
2x 32GB DDR4 2400 ECC REG
4x CBL-SAST-0507
MCP-220-83605-0N
MCP-210-83601-0B
2x INTEL S4600 240GB
10x TOSHIBA MG06ACA10TE

 

[Jeggs101]

I haven't but isn't persistent write cache on the actual storage device unnecessary with ZFS? ZFS was built specifically with caching layers. I'm really interested in your results to see which hypothesis is correct.

 

[Joze Volf]

It is necessary for fast sync writes. Cache flushing is the key. Why do you think enterprise SSDs have capacitors/power loss protection and perform better in writes than similar consumer models when used in ZFS or Storage Spaces (not considering superior endurance)? Same basic concept. Write back cache on device itself actually can't be disabled because there is no need to.

 

[Jeggs101]

You're probably right. I've just always thought about keeping classic write tiers. Especially now that you can use Optane for ZIL and SLOG