On 6/22/07, Jon Nelson <jnelson-linux-raid@xxxxxxxxxxx> wrote:
On Thu, 21 Jun 2007, Raz wrote: > What is your raid configuration ? > Please note that the stripe_cache_size is acting as a bottle neck in some > cases. Well, it's 3x SATA drives in raid5. 320G drives each, and I'm using a 314G partition from each disk (the rest of the space is quiescent).
what is the chunk size ?. Please note that a raid performance is dependent on the access pattern to the disks. What is this raid aimed to do ? more reads ? more writes ? If you can control the access pattern , you might be able to increase performance.
> On 6/21/07, Jon Nelson <jnelson-linux-raid@xxxxxxxxxxx> wrote: > > > > I've been futzing with stripe_cache_size on a 3x component raid5, > > using 2.6.18.8-0.3-default on x86_64 (openSUSE 10.2). > > > > With the value set at 4096 I get pretty great write numbers. > > 2048 and on down the write numbers slowly drop. > > > > However, at values above 512 the 'check' performance is terrible. By > > 'check' performance I mean the value displayed by /proc/mdstat after > > I issue: > > > > echo check > /sys/block/md0/md/sync_action > > > > When I say "terrible" I mean < 3MB/s. > > When I use 384, the performance goes to ~70MB/s > > 512.. 72-73MB/s > > 640.. 73-74MB/s > > > > 768.. 3300 K/s. Wow! > > > > Can somebody 'splain to me what is going on? > > > > -- > > Jon Nelson <jnelson-linux-raid@xxxxxxxxxxx> > > - > > 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 > > > > > -- > Raz > > > -- Jon Nelson <jnelson-linux-raid@xxxxxxxxxxx> - 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
-- Raz - 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
