On Mon, Nov 29, 2010 at 10:42:29AM +0100, Andi Kleen wrote: > Dave Chinner <david@xxxxxxxxxxxxx> writes: > > > > To avoid this problem, keep a count of the number of ->release calls > > made on an inode. For most cases, an inode is only going to be opened > > once for writing and then closed again during it's lifetime in > > cache. Hence if there are multiple ->release calls, there is a good > > chance that the inode is being accessed by the NFS server. Hence > > count up every time ->release is called while there are delalloc > > blocks still outstanding on the inode. > > Seems like a hack. It would be cleaner and less fragile to add a > explicit VFS hint that is passed down from the nfs server, similar > to the existing open intents. Agreed. However, we've been asking for the nfsd to change it's behaviour for various operations for quite some time (i.e. years) to help filesystems behave better, but and we're no closer to having it fixed now than we were 3 or 4 years ago. What the nfsd really needs is an an open file cache so that IO looks like normal file IO rather than every write being an "open-write-close" operation.... While we wait for nfsd to be fixed, we've still got people reporting excessive fragmentation during concurrent sequential writes to nfs servers running XFS, so we really need some kind of fix for the problem... 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
