On Mon, May 12, 2008 at 11:53:57AM +1000, Neil Brown wrote: > On Friday May 9, jesper@xxxxxxxx wrote: > > > > When I disabled the NFS-server and rand my "real-world" program on a > > single processor (make -j 1). It ran through fine. It basically > > gets around 20 million chunks out of differnet file and assemble the > > chuncks in a few other files. This processes more or less 5 individual > > sections, so make can run effectively with a concurrency of 5. > > (For linux-nfs readers: the problem is that repeatedly opening a given > file sometimes returns a ENOENT - http://lkml.org/lkml/2008/5/9/15). > > The mention of an NFS-server made my ears prick up... > > Do I understand correctly that the problem only occurs when you have > 48 clients hammering away at the filesystem in question? > > Could the clients be accessing the same file that you are experiencing > problems with? Or one of the directories in the path (if so, how > deep). > > How many different files to these 20 million chunks come from? And > how does that number compare with the first number from > grep dentry /proc/slabinfo > ?? > > The NFS server does some slighty strange things with the dcache if the > object being access is not in the cache. > > Also, can get a few instances of > grep '^fh' /proc/nfs/rpc/nfsd I think you meant /proc/net/rpc/nfsd. --b. > > while things are going strange. The numbers are: > * fh <stale> <total-lookups> <anonlookups> <dir-not-in-dcache> <nondir-not-in-dcache> > > That will show us if it is looking for things that aren't in the > dcache. > > Finally, if the filesystem export with "subtree_check" or > "nosubtree_check"? > Does it make a difference if you switch the setting of this flag and > re-export? > > NeilBrown > -- > To unsubscribe from this list: send the line "unsubscribe linux-kernel" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > Please read the FAQ at http://www.tux.org/lkml/ -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
