I built a raid5 with 2 devices (and --assume-clean) using 2x 4GB partitions (not logical volumes). I then grew it to 3 devices. The reshape speed is really really slow. vmstat shows I/O like this: 0 0 212 25844 141160 497484 0 0 0 612 673 1284 0 6 93 0 0 0 212 25164 141160 497748 0 0 0 19 594 1253 1 4 95 0 0 0 212 25044 141160 498004 0 0 0 0 374 445 0 1 99 0 1 0 212 25220 141164 498000 0 0 0 23 506 1149 0 3 96 1 0 0 212 25500 141164 498004 0 0 0 3 546 1416 0 5 95 0 The min/max is 1000/200000. What might be going on here? Kernel is 2.6.25.11 (openSUSE 11.0 x86-64 stock) /proc/mdstat for this entry: md99 : active raid5 sdd3[2] sdc3[1] sdb3[0] 3903744 blocks super 1.0 level 5, 64k chunk, algorithm 2 [3/3] [UUU] [=>...................] reshape = 8.2% (324224/3903744) finish=43.3min speed=1373K/sec This is on a set of devices capable of 70+ MB/s. No meaningful change if I start with 3 disks and grow to 4, with or without bitmap. -- Jon -- 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