Re: Kernel error during btrfs balance

[Erik Logtenberg <erik@logtenberg.eu>]

On 01/18/2011 01:54 AM, Yan, Zheng wrote:
> On Mon, Jan 17, 2011 at 10:14 PM, Erik Logtenberg <erik@logtenberg.eu> wrote:
>> Hi,
>>
>> btrfs balance results in:
>>
>> http://pastebin.com/v5j0809M
>>
>> My system: fully up-to-date Fedora 14 with rawhide kernel to make btrfs
>> balance do useful stuff to my free space:
>>
>> kernel-2.6.37-2.fc15.x86_64
>> btrfs-progs-0.19-12.fc14.x86_64
>>
>> Filesystem had 0 bytes free, should be 45G, so on darklings advice I ran
>> btrfs balance on the fs, while doing heavy I/O (re-running 5 backup jobs
>> that had failed due to ENOSP).
>> Up until the crash, btrfs balance did retrieve a couple of Gigs free
>> space though, so that part of the plan worked just fine.
>>
> 
> Please try 2.6.36 kernel.

Thanks for your (short) advice. Could you please elaborate. I was in
fact using a 2.6.35.10-74.fc14.x86_64 kernel before, but darkling
adviced me to switch to a newer kernel to reclaim free space by
balancing -- the idea was that newer kernels have better balancing
implementation, more effective at reclaiming free space.

Now your advice is to take a small step back again, from 2.6.37 to
2.6.36 (which is still higher than the 2.6.35 I was using before). Is
that because you think that 2.6.37 may have introduced the bug that I
ran into? Do you think that 2.6.36 is still recent enough to have the
effective balancing so that I will in fact be able to reclaim some free
space? Or is is just a shot in the dark with no reasoning whatsoever ;)

Please don't feel offended, but from your 4-word sentence I really can't
tell.

Thanks,

Erik.