On 02/08/2014 07:17 PM, Markus Falb wrote: > > On 08.Feb.2014, at 11:25, Mogens Kjaer wrote: > >> On 02/07/2014 11:47 PM, Matt wrote: >>> Having a >>> single drive is slowing down reads as well, I think. >> >> This depends upon how the RAID is set up. > > No, mdraid 1 is mdraid 1. > >> A standard Linux RAID1 setup does not give better reading >> performance when reading large files than a single disk. >> >> I don't know if the RAID system is cleaver enough to >> save some seek time. > > Process X is utilizing only one single disk, so no performance gain. > But if you have 2 processes in parallel, then you potentially have a gain, because the process Y can read from another disk. > > process X -> disk 0 > process Y -> disk 1 > >> In order to get better read performance you'll have >> to set it up as RAID10 with far copies. > > Yes, mdraid 10 could be a solution for the "1 process should utilize more than one disk" goal. > I haven't tried it though, what a shame. > > Why is that far copies thing important? > Better read from "the horses mouths": https://en.wikipedia.org/wiki/Non-standard_RAID_levels#Linux_MD_RAID_10 -- Ljubomir Ljubojevic (Love is in the Air) PL Computers Serbia, Europe StarOS, Mikrotik and CentOS/RHEL/Linux consultant