11 August 2011 16:58, mark delfman <markdelfman@xxxxxxxxxxxxxx> wrote: > I seem to have hit a significant hard stop in MD RAID1/10 performance > which seems to be linked to a single CPU thread. > > I am using extremely high speed (IOPS) internal block devices – 8 in > total. They are capable of achieving > 1million iops. > > However if I use RAID1 / 10 then MD seems to use a single thread which > will reach 100% CPU utilisation (single core) at around 200K IOPS. > Limiting the entire performance to around 200K. > > If I use say 4 x RAID1 / 10’s and a RAID0 on top – I see not much > greater results. (although the theory seems to say I should and there > are now 4 CPU threads running, it still seems to hit 4 x 100% at maybe > 350K). > > Is there any way to increase the number of threads per RAID set? Or > any other suggestions on configurations? (I have tried every > permutation of R0+R1/10’s) > > Thank you for any advice. > > > Mark > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Maybe create separate MD RAID1 devices, then a new MD device with RAID0? (instead of using mdadm RAID"10") /M -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
