On Thu, May 30, 2019 at 05:16:14PM +0100, Robin Hill wrote: > On Thu May 30, 2019 at 05:58:34PM +0200, keld@xxxxxxxxxx wrote: > > > On Thu, May 30, 2019 at 04:37:43PM +0200, Reindl Harald wrote: > > > > > > > > > Am 30.05.19 um 12:04 schrieb keld@xxxxxxxxxx: > > > > you need to clarify which layout you use with md raid10. > > > > the layouts are near, far and offset, with very different performance characteristics. > > > > far and offset are designed to be faster than near, which I understand that you use. > > > > So why are you using the slowest md raid10 layout, and not mentioning this fact? > > > > > > besides that when you install a distribution like Fedora "near" is > > > default for pure reads it shouldn't be slower than RAID1 at all, just > > > read from both mirrors of the stripe > > > > near is mdadm default, so people often do not realize the faster options. > > > Are they not only faster on physical disks? The OP indicated they have > an SSD and an NVMe, so I don't see why any of the RAID-10 variations > would perform any better. I can agree with you, but some measurements have given results that they are faster even on ssds. I dont know why. Also I understood that HDs were also involved in the setups. keld
