On 5/25/2013 5:36 PM, Jean-Marc wrote: > Hi guys, > > I am trying to measure the perf' of RAID arrays to be sure of the layout > I'll use for my future set up. > > Based on this article, RAID10,f2 seems to be the best set up: > https://raid.wiki.kernel.org/index.php/Performance > > But if I create a RAID10,f2 array (ext4 FS) and if I compare its perf' > against a RAID1 arrays using bonnie++, I do not see any big differences. ... > May be I am doing something wrong.
Yes, you are. You're using only 2 disk drives. The md/RAID10 module with two drives will perform nearly identical to RAID1. Adding insult to injury you are using 6GB partitions in your testing setup. The "layouts" of md/RAID10 are only of benefit when you use the entire disk capacity, or a very large portion of it. These layouts obtain some advantage be changing the behavior of the disk head and thus read latency. With a 6GB partition on a 1/2TB disk drive, the heads will never travel outside of a single track. You really need to read and comprehend much more about md, or simply listen to an expert: For two disks, use RAID1. PERIOD. End of story. Screwing with anything else is a massive waste of your time. If you have 3 or more disks, then you can worry about layouts. -- Stan -- To UNSUBSCRIBE, email to debian-user-requ...@lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmas...@lists.debian.org Archive: http://lists.debian.org/51a14a2b.9020...@hardwarefreak.com
