On Wed, Jun 29, 2011 at 10:01:11AM -0400, Christoph Hellwig wrote: > wbc->nonblocking is never set, so this whole code has been unreachable > for a long time. I'm also not sure it would make a lot of sense - > we'd rather finish our writeout after a short wait for the ilock > instead of cancelling the whole ioend. The problem that the non-blocking code is trying to solve is only obvious when the disk subsystem is fast enough to drive the flusher thread to being CPU bound. e.g. when you have a disk subsystem doing background writeback 10GB/s and the flusher thread is put to sleep for 50ms while we wait for the lock, it can now only push 9.5GB/s. If we just move on, then we'll spend that 50ms doing useful work on another dirty inode rather than sleeping onthis one and hence maintaining a 10GB/s background write rate. I'd suggest that the only thing that should be dropped is the wbc->nonblocking check. Numbers would be good to validate that this is still relevant, but I don't have a storage subsystem with enough bandwidth to drive a flusher thread to being CPU bound... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx _______________________________________________ xfs mailing list xfs@xxxxxxxxxxx http://oss.sgi.com/mailman/listinfo/xfs
