On Thu, Sep 03, 2009 at 03:52:01PM +1000, Dave Chinner wrote: > > XFS did the mistake of trusting the VM, while everyone more or less > > overrode it. Removing all those checks and writing out much larger > > data fixes it with a relatively small patch: > > > > http://verein.lst.de/~hch/xfs/xfs-writeback-scaling > > Careful: > > - tloff = min(tlast, startpage->index + 64); > + tloff = min(tlast, startpage->index + 8192); > > That will cause 64k page machines to try to write back 512MB at a > time. This will re-introduce similar to the behaviour in sles9 where > writeback would only terminate at the end of an extent (because the > mapping end wasn't capped like above). Pretty good point, any applies to all the different things we discussed recently. Ted, should be maybe introduce a max_writeback_mb instead of the max_writeback_pages in the VM, too? -- To unsubscribe from this list: send the line "unsubscribe linux-ext4" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
