[btrfs-transacti] & btrfs-endio-wri] - WAS: Re: [btrfs-delalloc-]

[Proskurin Kirill <k.proskurin@corp.mail.ru>]

On 06/27/2011 05:21 PM, Hubert Kario wrote:
> On Monday 27 of June 2011 11:04:06 Proskurin Kirill wrote:
>> Hello all.
>>
>> What we have:
>> SL6 - kernel 2.6.32-131.2.1.el6.x86_64
>> btrfs on mdadm RAID5 with 8 HDD - 27T partition.
>>
>> I see this at top:
>> 1182 root      20   0     0    0    0 R 100.0  0.0  16:39.73
>> [btrfs-delalloc-]
>>
>> And LA is grow. What is this and how can I fix it?
>
> delalloc is a delayed allocation kernel thread -- it probably means something
> is writing large amounts of data to the file system
>
> 2.6.32 is *old* as far as btrfs is concerned, there have been many bugs fixed
> and performance improvements since

Ok - I upgrade to 2.6.39-2 but it is seems to all things get worse.
Now I see [btrfs-transacti] & btrfs-endio-wri] 80-100% all the time and 
io performance looks like lower then before.

Our scribe daemon in state D most of the time with half of a normal 
load. Only kernel was changed.

Any performance tune recommendation?

-- 
Best regards,
Proskurin Kirill