Re: [dm-devel] livelock on MD RAID5

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 




On Mon, 19 Jan 2015, Mikulas Patocka wrote:

> Hi Neil
> 
> I saw your patch "md/raid5: avoid livelock caused by non-aligned writes". 
> That patch is only for RAID 6, but we are seeing similar livelock on RAID5 
> (mdX_raid5 is constantly looping in 
> raid5d/handle_active_stripes/handle_stripe/ops_run_io and some submitted 
> bios get stuck). The livelock happens when we issue I/O and simulate disk 
> failure.
> 
> Do you think that the same issue could happen on RAID5 too?
> 
> Do you think that the patch "md/raid5: fetch_block must fetch all the 
> blocks handle_stripe_dirtying wants." could fix it?
> 
> Mikulas

So, we verified that this RAID5 livelock was introduced in patch 
67f455486d2ea20b2d94d6adf5b9b783d079e321. A patch 
a40687ff73a5b14909d6aa522f7d778b158911c5 fixes a livelock in RAID6, but a 
similar livelock was introduced in RAID5, that is still unfixed upstream.

Mikulas
--
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




[Index of Archives]     [Linux RAID Wiki]     [ATA RAID]     [Linux SCSI Target Infrastructure]     [Linux Block]     [Linux IDE]     [Linux SCSI]     [Linux Hams]     [Device Mapper]     [Device Mapper Cryptographics]     [Kernel]     [Linux Admin]     [Linux Net]     [GFS]     [RPM]     [git]     [Yosemite Forum]


  Powered by Linux