On Wed, Jun 30, 2010 at 10:14:52PM +1000, Nick Piggin wrote: > On Wed, Jun 30, 2010 at 08:13:54PM +1000, Dave Chinner wrote: > > On Thu, Jun 24, 2010 at 01:03:04PM +1000, npiggin@xxxxxxx wrote: > > > Problem with inode reclaim is that it puts inodes into I_FREEING state > > > and then continues to gather more, during which it may iput, > > > invalidate_mapping_pages, be preempted, etc. Holding these inodes in > > > I_FREEING can cause pauses. > > > > What sort of pauses? I can't see how holding a few inodes in > > I_FREEING state would cause any serious sort of holdoff... > > Well if the inode is accessed again, it has to wait for potentially > hundreds of inodes to be found from the LRU, pagecache invalidated, > and destroyed. So it's a theoretical concern you have, not something that's actually been demonstrated as a problem? As it is, If the inode is accessed immediately after teardown has started, then we failed to hold on to the inode at a higher level for long enough. Changing the I_FREEING behaviour is trying to address the issue at the wrong level... Cheers, Dave. -- Dave Chinner david@xxxxxxxxxxxxx -- 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
