| Date | Mon, 12 May 2008 10:24:03 +1000 | From | David Chinner <> | Subject | Re: [patch 10/21] buffer heads: Support slab defrag |
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On Fri, May 09, 2008 at 08:08:41PM -0700, Christoph Lameter wrote: > Defragmentation support for buffer heads. We convert the references to > buffers to struct page references and try to remove the buffers from > those pages. If the pages are dirty then trigger writeout so that the > buffer heads can be removed later.
Oh, no, please don't trigger more random single page writeback from memory reclaim. We shoul dbe killing the VM's use of ->writepage, not encouraging it.
If you are going to clean bufferheads (or pages), please clean entire mappings via ->writepages as it leads to far superior I/O patterns and a far higher aggregate rate of page cleaning.....
Cheers,
Dave. -- Dave Chinner Principal Engineer SGI Australian Software Group
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