On Tue, Jun 8, 2010 at 10:33 AM, besson3c <j...@netmusician.org> wrote: > On heavy reads or writes (writes seem to be more problematic) my load > averages on my VM host shoot up and overall performance is bogged down. I > suspect that I do need a mirrored SLOG, but I'm wondering what the best way is
The load that you're seeing is probably iowait. If that's the case, it's almost certainly the write speed of your pool. A raidz will be slow for your purposes, and adding a zil may help. There's been lots of discussion in the archives about how to determine if a log device will help, such as using zilstat or disabling the zil and testing. You may want to set the recordsize smaller for the datasets that contain vmdk files as well. With the default recordsize of 128k, a 4k write by the VM host can result in 128k being read from and written to the dataset. What VM software are you using? There are a few knobs you can turn in VBox which will help with slow storage. See http://www.virtualbox.org/manual/ch12.html#id2662300 for instructions on reducing the flush interval. -B -- Brandon High : bh...@freaks.com _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
