Messages in this thread | | | Date | Wed, 30 Sep 2009 09:30:34 +0800 | From | Wu Fengguang <> | Subject | Re: regression in page writeback |
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On Wed, Sep 30, 2009 at 07:39:36AM +0800, Dave Chinner wrote: > On Mon, Sep 28, 2009 at 10:25:24AM -0400, Chris Mason wrote: > > On Mon, Sep 28, 2009 at 11:07:00AM +1000, Dave Chinner wrote: > > > In the context of the setup I was talking about, I meant is that sync > > > IO _should_ be unthrottled because it is self-throttling by it's > > > very nature. The current code makes no differentiation between the > > > two. > > > > This isn't entirely true anymore. WB_SYNC_ALL is turned into a sync > > bio, which is sent down with higher priority. There may be a few spots > > that still need to be changed for it, but it is much better than it was. > > Oh, I didn't realise that had changed - when did WRITE_SYNC_PLUG get > introduced?
About 5 months before, when Linus complained something similar :)
http://lkml.org/lkml/2009/4/6/114
Thanks, Fengguang
> FWIW, I notice that __block_write_full_page(), gfs2, btrfs > and jdb use WRITE_SYNC_PLUG to implement this, but it appears that > filesystems that have their own writeback code (e.g. XFS) have not > been converted (gfs2 and btrfs being the exceptions). > > Oh well, something else that needs tweaking in XFS... > > Cheers, > > Dave. > -- > Dave Chinner > david@fromorbit.com
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