On Tue, Jan 31, 2012 at 11:53:53AM +0100, Jan Kara wrote: > On Tue 31-01-12 11:14:15, Dave Chinner wrote: > > I also found this oddity on both XFS and ext4: > > > > flush-253:32-3400 [001] 1936151.384563: writeback_start: bdi 253:32: sb_dev 0:0 nr_pages=-898403 sync_mode=0 kupdate=0 range_cyclic=1 background=1 reason=background > > flush-253:32-3400 [005] 1936151.455845: writeback_start: bdi 253:32: sb_dev 0:0 nr_pages=-911663 sync_mode=0 kupdate=0 range_cyclic=1 background=1 reason=background > > flush-253:32-3400 [006] 1936151.596298: writeback_start: bdi 253:32: sb_dev 0:0 nr_pages=-931332 sync_mode=0 kupdate=0 range_cyclic=1 background=1 reason=background > > flush-253:32-3400 [006] 1936151.719074: writeback_start: bdi 253:32: sb_dev 0:0 nr_pages=-951001 sync_mode=0 kupdate=0 range_cyclic=1 background=1 reason=background > > > > That's indicating the work->nr_pages is starting extremely negative, > > which should not be the case. The highest I saw was around -2m. > > Something is not working right there, as writeback is supposed to > > terminate if work->nr_pages < 0.... > Ugh, what kernel is this? The tracepoint is just a couple of lines after > if (work->nr_pages <= 0) > break; > so I really don't see how that could happen. Neither can I - it is the latest Linus kernel (3.3-rc1+). I even upgraded trace-cmd to the latest in case that was the problem, but it didn't make any difference. I haven't worked it out yet. Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- 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
