Re: [PATCH] 2.6.11-mm1 ext3 writepages support for writeback mode

[Badari Pulavarty <pbadari@us.ibm.com>]

On Fri, 2005-03-04 at 15:43, Andrew Morton wrote:
> Badari Pulavarty <pbadari@us.ibm.com> wrote:
> >
> > Hi Andrew,
> > 
> > Here is the 2.6.11-mm1 patch for adding writepages support
> > for ext3 writeback mode. Could you include it in -mm tree ?
> 
> spose so.  Does it work?
> 
> Do you have any benchmarking results handy?

I did few benchmarks earlier which showed 5-7% improvement
on throughput. I will run the numbers again.

> 
> > +static int
> > +ext3_writeback_writepages(struct address_space *mapping, 
> > +				struct writeback_control *wbc)
> > +{
> > +	struct inode *inode = mapping->host;
> > +	handle_t *handle = NULL;
> > +	int err, ret = 0;
> > +
> > +	if (!mapping_tagged(mapping, PAGECACHE_TAG_DIRTY))
> > +		return ret;
> 
> Can we please add a comment explaining why this is here?  I've already
> forgotten why we put it there.

This is to avoid not starting the journal when we are trying to
destroy journal inode. I will add comments.

>       journal_destory()
>               iput(journal inode)
>                       do_writepages()
>                               generic_writepages()
>                                       ext3_writeback_writepage()
>                                               journal_start()

 
Thanks,
Badari