On Wed, 31 Mar 2010, Karsten Weiss wrote:
But frankly at the moment I care the most about the single-threaded case because if we put e.g. user homes on this server I think they would be severely disappointed if they would have to wait 2m42s just to extract a rather small 50 MB tarball. The default 7m40s without SSD log were unacceptable and we were hoping that the F20 would make a big difference and bring the performance down to acceptable runtimes. But IMHO 2m42s is still too slow and disabling the ZIL seems to be the only option.
Is extracting 50 MB tarballs something that your users do quite a lot of? Would your users be concerned if there was a possibility that after extracting a 50 MB tarball that files are incomplete, whole subdirectories are missing, or file permissions are incorrect?
The Sun Flash Accelerator F20 was not strictly designed as a zfs log device. It was originally designed to be a database accelerator. It was repurposed for zfs slog use because it works. It is a bit wimpy for bulk data. If you need fast support for bulk writes, perhaps you need something like STEC's very expensive ZEUS SSD drive.
Bob -- Bob Friesenhahn bfrie...@simple.dallas.tx.us, http://www.simplesystems.org/users/bfriesen/ GraphicsMagick Maintainer, http://www.GraphicsMagick.org/ _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
