SSD cache on linux software raid?

1337

I looking at a software raid6 array of spinning rust for storing backups. Drives will be something like 3.5" Exos 12TB (7200 rpm).

Is it possible to use an SSD drive as a write cache for linux md raid?
I've read somewhere that LVM has that feature.

Is it worthwhile? Anyone here that have experience with it?

Network is 10GbE so having up to 1 Gbyte/s transfer rate is what I'm after.

scottalanmiller

@Pete-S said in SSD cache on linux software raid?:

Is it possible to use an SSD drive as a write cache for linux md raid?

Yes and no. MD RAID itself is just the RAID. But like most things in UNIX, you don't do "that with that", but there is a separate cache mechanism to do that with Linux regardless of the RAID.

Look into: dm-cache and flashcache

scottalanmiller

https://access.redhat.com/documentation/en-us/red_hat_enterprise_linux/6/html/logical_volume_manager_administration/lvm_cache_volume_creation

LVM has some of that stuff, too.