Excerpts from Christoph Hellwig's message of 2011-04-21 14:08:05 -0400: > On Thu, Apr 21, 2011 at 02:02:43PM -0400, Chris Mason wrote: > > For this program, they are almost all dirty pages. > > > > I tried patching it to give up if we seek but it is still pretty slow. > > There's something else going on in addition to the xfs clustering being > > too aggressive. > > I'm not sure where you this beeing to agressive from - it's doing > exactly the same amount of I/O as a filesystem writing out a single > page from ->writepage or using write_cache_pages (either directly > or as a copy) as ->writepages. The only thing special compared to > the no ->writepages case is that it's submitting a large I/O > from the first ->writepage call. > Ok, I see what you mean. The clustering code stops once it hits nr_to_write, I missed that. So we shouldn't be doing more than a single writepages call. -chris -- 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
