ZFS: Making L2ARC Dumb On Purpose
I have a NAS. It runs a ZFS raidz1 that’s not particularly fast (reads 300~350MB/s max?). It’s also attached to a 10gb LAN. So I thought: wouldn’t it be nice if I could just plonk in an SSD cache and saturate that? I put in a drive, zpool add zfs cache/dev/nvme0n1p1’d1 it, read a bunch of files, saw the cache utilisation line go up in monitoring, got exited, and got absolutely no improvement in read speeds. ...