zfs slog l2arc

Hello, I have a server with E5 2620 v4, 64GB ram and 4x1tb mushkin Reactor SSD (I know it's consumer grade but it's in ZFS striped mirrored, aka raid 10). Overall I'm happy with performance but I still see 5-15% IO delay during peak load. CPU usage always around 20-40% and RAM is 80-90% all the...