Hi - It seems our MD raid rebuild speeds are very slow with the new Fedora 2.6.32.9-70 kernel. We're only getting ~13MB/s: [root@xback2 ~]# cat /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 sdb1[0] sdj1[10](S) sdk1[9] sdl1[8] sdi1[7] sdh1[6] sdg1[5] sdf1[4] sde1[3] sdd1[2] sdc1[1] 8788959360 blocks level 5, 32k chunk, algorithm 2 [10/10] [UUUUUUUUUU] [=====>...............] resync = 29.3% (286397320/976551040) finish=897.2min speed=12819K/sec The maximum rebuild speed is at the default 200000K/s. The drives are connected to a 3ware 9650SE-16ML controller on PCI-Express. There seem to be hundreds of async/X threads, where X goes up to 129 at least. The md0_raid5 process is using at least 80% of the CPU on this dual core Athlon 7750 system. Has anything changed recently in the kernel. I don't remember md0_raid5 being so processor inefficient, slow at rebuilding or creating hundreds of kernel threads. Are these async/X threads documented anywhere? Thanks Jeremy -- 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