Re: [PATCH 0/10] Per-bdi writeback flusher threads v12

["Zhang, Yanmin" <yanmin_zhang@linux.intel.com>]

On Thu, 2009-06-25 at 12:41 +0200, Jens Axboe wrote:
> Hi,
> 
> Here's the 12th version of the writeback patches. Changes since v11:
> 
> - Fixup kthread_run() error check, it should use IS_ERR() instead of
>   checking for NULL. Thanks Andrew.
> - Fix a silly buglet that would quickly respawn otherwise idle threads
>   once they had exited. This was due to an inverted if test. Didn't cause
>   any harm except potentially too many writeback threads setting idle in
>   the system.
> - Integrate kupdate periodic writeback with the explicit writeback. Cleans
>   that part up.
> - Update to 2.6.31-rc1. With the recent patches from viro and hch, v11
>   did not apply cleanly at all to 2.6.31-rc1.
> 
> For ease of patching, I've put the full diff here:
> 
>   http://kernel.dk/writeback-v12.patch
> 
> and also stored this in a writeback-v12 branch that will not change,
> you can pull that into Linus tree from here:
> 
>   git://git.kernel.dk/linux-2.6-block.git writeback-v12
> 

> Please test and report results/interesting finds.
I tested it against 2.6.31-rc1 on a couple of machines.
1) System didn't hang;
2) Comapring with previous bdi flusher versions, I didn't find clear performance
different.

>  Thanks! The target
> for this patchset is 2.6.32 and it'll be sitting (and has been for the past