On Sat, Oct 22, 2011 at 11:11:35AM +0800, Wu Fengguang wrote:
> > > btw, with the I_SYNC case converted, it's actually no longer necessary
> > > to keep a standalone b_more_io_wait. It should still be better to keep
> > > the list and the above error check for catching possible errors and
> > > the flexibility of adding policies like "don't retry possible blocked
> > > inodes in N seconds as long as there are other inodes to work with".
> > >
> > > The below diff only intends to show the _possibility_ to remove
> > > b_more_io_wait:
> > Good observation. So should we introduce b_more_io_wait in the end? We
> > could always introduce it when the need for some more complicated policy
> > comes...
> >
>
> I have no problem removing it if you liked it more. Anyway, let me
> test the idea out first (just kicked off the tests).
When removing b_more_io_wait, performance is slightly dropped
comparing to the full more_io_wait patchset.
3.1.0-rc9-ioless-full-more_io_wait-next-20111014+ 3.1.0-rc9-ioless-full-more_io_wait-x-next-20111014+
------------------------ ------------------------
45.30 +6.3% 48.14 thresh=1G/ext3-1dd-4k-8p-4096M-1024M:10-X
48.23 -2.0% 47.27 thresh=1G/ext4-100dd-4k-8p-4096M-1024M:10-X
54.21 -2.6% 52.80 thresh=1G/ext4-10dd-4k-8p-4096M-1024M:10-X
56.07 -0.3% 55.91 thresh=1G/ext4-1dd-4k-8p-4096M-1024M:10-X
45.12 -5.8% 42.49 thresh=1G/xfs-100dd-4k-8p-4096M-1024M:10-X
53.94 -1.2% 53.27 thresh=1G/xfs-10dd-4k-8p-4096M-1024M:10-X
55.66 -0.1% 55.63 thresh=1G/xfs-1dd-4k-8p-4096M-1024M:10-X
358.53 -0.8% 355.51 TOTAL write_bw
I'll try to reduce the changes and retest.
In general it looks better we first root case the "decreasing wrote
pages by writeback_single_inode() over time" problem before looking
into further steps..
Thanks,
Fengguang
--
To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
