On 01/29/09 21:32, Greg Mason wrote: > This problem only manifests itself when dealing with many small files > over NFS. There is no throughput problem with the network. > > I've run tests with the write cache disabled on all disks, and the cache > flush disabled. I'm using two Intel SSDs for ZIL devices. > > This setup is faster than using the two Intel SSDs with write caches > enabled on all disks, and with the cache flush enabled. > > My test would run around 3.5 to 4 minutes, now it is completing in > abound 2.5 minutes. I still think this is a bit slow, but I still have > quite a bit of testing to perform. I'll keep the list updated with my > findings. > > I've already established both via this list and through other research > that ZFS has performance issues over NFS when dealing with many small > files. This seems to maybe be an issue with NFS itself, where > NVRAM-backed storage is needed for decent performance with small files. > Typically such an NVRAM cache is supplied by a hardware raid controller > in a disk shelf. > > I find it very hard to explain to a user why an "upgrade" is a step down > in performance. For the users these Thors are going to serve, such a > drastic performance hit is a deal breaker...
Perhaps I missed something, but what was your previous setup? I.e. what did you upgrade from? Neil. _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
