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
