> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Dragan Marinkovic > Sent: Thursday, November 23, 2006 8:49 PM > To: linux-raid@xxxxxxxxxxxxxxx > Subject: Linux RAID version question > 2. RAIDs built with metadata version 0.9 does not always continue > rebuilding where they left off when last stopped (specifically on the > clean shutdown while the raid is still rebuilding). I have a followup question on your second point, as I've been coincidentally searching for the same feature. I'm running 2.6.17 with the MD_FEATURE_OFFSET_RECOVERY patches (and also have tried 2.6.18) and do not observe recovery/resync checkpoint behavior across clean array shutdowns (4 drive RAID 5). >From attempting to learn some of the md code, it appears the framework is there to support this, but I had to make the following changes to achieve desired behavior: --- drivers/md/md.c 2006-11-24 18:03:24.000000000 -0500 +++ drivers/md/md.c 2006-11-24 17:52:28.000000000 -0500 @@ -4883,7 +4883,6 @@ void md_do_sync(mddev_t *mddev) mddev->pers->sync_request(mddev, max_sectors, &skipped, 1); if (!test_bit(MD_RECOVERY_ERR, &mddev->recovery) && - test_bit(MD_RECOVERY_SYNC, &mddev->recovery) && !test_bit(MD_RECOVERY_CHECK, &mddev->recovery) && mddev->curr_resync > 2) { if (test_bit(MD_RECOVERY_SYNC, &mddev->recovery)) { @@ -4893,6 +4892,7 @@ void md_do_sync(mddev_t *mddev) "md: checkpointing recovery of %s.\n", mdname(mddev)); mddev->recovery_cp = mddev->curr_resync; + mddev->sb_dirty = 1; } } else mddev->recovery_cp = MaxSector; I removed the check for MD_RECOVERY_SYNC, which was preventing a clean shutdown during recovery from hitting the code that sets recovery_offset. I was a bit confused about the logic there, as the MD_RECOVERY_SYNC flag is checked again within that code block.. (?) I have hit the resync checkpoint code above, but the superblock is not updated unless I set sb_dirty. Am I missing something that would allow me to achieve this behavior without such changes? If not, is there any reason why the recovery does not currently checkpoint across array stoppage? Is this considered safe in terms of functional correctness (i.e., is my data at risk if I "continue" a recovery in this fashion)? Any insight is greatly appreciated, thanks in advance... Brian - 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
