>On Monday June 22, Ryan_MichaelS@xxxxxxx wrote: > Occasionally one of my devices with a 4 drive raid10 array resyncs very >> slowly. Typical resync speed is in the 50-60 MB/sec range. When >> running slow the speed is around 7-10 MB/sec. sync_speed_min is set to >> 20,000, max is set to 200,000. By setting sync_speed_min to 5000 I can >> slow the sync further, but setting it back to 20000 doesn't fix the >> speed. Other IO on the system is normal. The drives and the CPU are >> not maxed. >> >> I don't know what is triggering this slow sync state. Once in this >> state it will continue until the build completes. >> >> Any idea what might be happening here? I'm running Debian with a 2.6.22 >> kernel. > > Not really... > There have been a couple of bugs that cause resync to go faster than > ..it should, but I can't think of anything that would make it go slower > than sync_speed_min unless that the the fastest that the storage > subsystem could handle. > > Is this just a default raid10 with 'near=2' as the layout? > > NeilBrown Yep, default raid12, near=2. The device can handle 50-60 MB/sec. When the resync is running slow there doesn't seem to be anything else on the system that is consuming CPU or IO resources. Thanks for the info, I'll keep digging. - Michael -- 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
