Re: MD/RAID time out writing superblock

Chris Webb
2009-09-07T12:03:56Z

Chris Webb <chris@arachsys.com> writes:

> I have a bitmap on the array, but sometimes when I remove and re-add a
> failed component, it doesn't seem to use the bitmap and does a lengthy full
> recovery instead. One example that's ongoing at the moment:-
>
> [=>...................] recovery = 5.7% (40219648/703205312) finish=7546.3min speed=1463K/sec
> bitmap: 34/126 pages [136KB], 8192KB chunk
>
> which is rather painful and has to be throttled back with speed_limit_max to
> avoid the virtual machines running on top of it from having extremely poor IO
> latency.

I've also noticed that during this recovery, I'm seeing lots of timeouts but
they don't seem to interrupt the resync:

05:47:39 ata5.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
05:47:39 ata5.00: cmd ec/00:01:00:00:00/00:00:00:00:00/00 tag 0 pio 512 in
05:47:39 res 40/00:00:00:4f:c2/00:00:00:00:00/40 Emask 0x4 (timeout)
05:47:39 ata5.00: status: { DRDY }
05:47:39 ata5: hard resetting link
05:47:49 ata5: softreset failed (device not ready)
05:47:49 ata5: hard resetting link
05:47:49 ata5: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
05:47:49 ata5.00: configured for UDMA/133
05:47:49 ata5: EH complete

08:17:39 ata5.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
08:17:39 ata5.00: cmd ec/00:01:00:00:00/00:00:00:00:00/00 tag 0 pio 512 in
08:17:39 res 40/00:00:35:83:f8/00:00:4d:00:00/40 Emask 0x4 (timeout)
08:17:39 ata5.00: status: { DRDY }
08:17:39 ata5: hard resetting link
08:17:49 ata5: softreset failed (device not ready)
08:17:49 ata5: hard resetting link
08:17:49 ata5: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
08:17:49 ata5.00: configured for UDMA/133
08:17:49 ata5: EH complete

10:22:39 ata5.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen
10:22:39 ata5.00: cmd ec/00:01:00:00:00/00:00:00:00:00/00 tag 0 pio 512 in
10:22:39 res 40/00:00:00:4f:c2/00:00:00:00:00/40 Emask 0x4 (timeout)
10:22:39 ata5.00: status: { DRDY }
10:22:39 ata5: hard resetting link
10:22:49 ata5: softreset failed (device not ready)
10:22:49 ata5: hard resetting link
10:22:50 ata5: SATA link up 3.0 Gbps (SStatus 123 SControl 300)
10:22:51 ata5.00: configured for UDMA/133
10:22:51 ata5: EH complete

Cheers,

Chris.