Re: [RFC] JBD ordered mode rewrite

From: Jan Kara
Date: Mon Mar 10 2008 - 12:30:51 EST


On Thu 06-03-08 14:05:03, Josef Bacik wrote:
> On Thursday 06 March 2008 12:42:09 pm Jan Kara wrote:
> > Hi,
> >
> > Below is my rewrite of ordered mode in JBD. Now we don't have a list of
> > data buffers that need syncing on transaction commit but a list of inodes
> > that need writeout during commit. This brings all sorts of advantages such
> > as possibility to get rid of journal heads and buffer heads for data
> > buffers in ordered mode, better ordering of writes on transaction commit,
> > simplification of some JBD code, no more anonymous pages when truncate of
> > data being committed happens. The patch has survived some light testing
> > but it still has some potential of eating your data so beware :) I've run
> > dbench to see whether we didn't decrease performance by different handling
> > of truncate and the throughput I'm getting on my machine is the same (OK,
> > is lower by 0.5%) if I disable the code in truncate waiting for commit to
> > finish... Also the throughput of dbench is about 2% better with my patch
> > than with current JBD.
> > Any comments or testing most welcome.
> >
> > Honza
>
> Just one nit, doesn't compile properly when jbd/ext3 are modules :). Thanks
> much,
Thanks for spotting this. Will fix :).

Honza
--
Jan Kara <jack@xxxxxxx>
SUSE Labs, CR
--
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
Please read the FAQ at http://www.tux.org/lkml/