Safe L2 only defer-write cache?
Posted: Thu Oct 27, 2022 2:27 pm
I've had some search in the form but maybe I'm too stupid to find the thread so I'm submitting a new topic.
I'm looking into PrimoCache for my upgraded NAS (Windows + PrimoCache + DrivePool + snapraid). I installed a evaluate version and read the document, and it says:
However, during the years SSD performance has increased and price has dropped dramatically, and in 2022 even NVMe raid 1 cache is quite affordable for data hoarders (e.g. some small optane sticks). Is it possible to implement a L2-only defer-write cache? there could be wearing on the SSD, however I think it's worth it to increase performance greatly for HDD drives.
I'm looking into PrimoCache for my upgraded NAS (Windows + PrimoCache + DrivePool + snapraid). I installed a evaluate version and read the document, and it says:
That's a big NO for NAS usage.Since cache index data is stored in memory, the risk of data loss is the same whether using L1 cache or L2 cache. Write-data on the L2 cache cannot be recovered to disk after a failure and restart.
However, during the years SSD performance has increased and price has dropped dramatically, and in 2022 even NVMe raid 1 cache is quite affordable for data hoarders (e.g. some small optane sticks). Is it possible to implement a L2-only defer-write cache? there could be wearing on the SSD, however I think it's worth it to increase performance greatly for HDD drives.