On Sat, 7 Dec 2019, John Stoffel wrote:
The biggest harm to performance here is really the RAID5, and if you can instead move to RAID 10 (mirror then stripe across mirrors) then you should be a performance boost.
Yeah, That's what I do. RAID10, and use LVM to join together as JBOD. I forgot about the raid 5 bottleneck part, sorry.
As Daniel says, he's got lots of disk load, but plenty of CPU, so the single thread for RAID5 is a big bottleneck.
I assume he wants to use LVM so he can create volume(s) larger than individual RAID5 volumes, so in that case, I'd probably just build a regular non-striped LVM VG holding all your RAID5 disks. Hopefully
Wait, that's what I suggested!
If you can, I'd get more SSDs and move to RAID1+0 (RAID10) instead, though you do have the problem where a double disk failure could kill your data if it happens to both halves of a mirror.
No worse than raid5. In fact, better because the 2nd fault always kills the raid5, but only has a 33% or less chance of killing the raid10. (And in either case, it is usually just specific sectors, not the entire drive, and other manual recovery techniques can come into play.) -- Stuart D. Gathman <stuart@xxxxxxxxxxx> "Confutatis maledictis, flammis acribus addictis" - background song for a Microsoft sponsored "Where do you want to go from here?" commercial. _______________________________________________ linux-lvm mailing list linux-lvm@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/linux-lvm read the LVM HOW-TO at http://tldp.org/HOWTO/LVM-HOWTO/
