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charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Am 12.06.24 um 09:06 schrieb Reindl Harald: > > > Am 12.06.24 um 02:14 schrieb Paul E Luse: >> On Wed, 12 Jun 2024 01:04:18 +0200 >> Reindl Harald wrote: >> >>> >>> >>> Am 11.06.24 um 20:31 schrieb Piergiorgio Sartor: >>>> I'm setting up a system with 2 SSD M.2 (NVME). >>>> >>>> I was wondering if would it be better, performace >>>> wise, to have a RAID-10 near layout or a RAID-1. >>>> >>>> Looking around I found only one benchmark: >>>> >>>> https://strugglers.net/~andy/blog/2019/06/02/exploring-different-linux-raid-10-layouts-with-unbalanced-devices/ >>>> >>>> Which uses mixed SSD, NVME and SATA. >>>> >>>> Does anybody have any suggestions, links, or >>>> ideas on the topic? >>>> >>>> BTW, practically speaking, what's the difference, >>>> between the two RAIDs? >>> >>> i wouldn't even consider a RAID10 with two disks, especially with SSD >>> and practically you end with a unsupported RAID1 because there are no >>> stripes with 2 disks >>> >>> >> I don't disagree but I would recommend you try each variation and >> measure the performance for yourself.  It's a great learning experience >> if you haven't done it before and there's nothing like trusting your >> own data over on your own system/config something that someone else has >> done when there are so many factors that can affect performance. > > the problem with benchmarks is that they often don't reflect mixed, > real-world performance - for virtual machine workload the "far" layout > wins in case of HDD > > with NVME RAID i pretend it don't matter enough to even waste your time and with only TWO disks thins might look compleltly different a 4 disk RAID10 in case of large reads can use all 4 drives at the same time while with only two disks there isn't much to gain when you end with a practical RAID1 but the complexer scheme the whole point of RAID10 is that you can double size *and* performance because of a least 4 disks and striping if performance *really* matters buy 4 NVME drives with half the size or just keep thins simple