To add to Bob's notes... On Feb 8, 2010, at 8:37 AM, Bob Friesenhahn wrote: > On Mon, 8 Feb 2010, Felix Buenemann wrote: >> >> I was under the impression, that using HW RAID10 would save me 50% PCI >> bandwidth and allow the controller to more intelligently handle its cache, >> so I sticked with it. But I should run some benchmarks in RAID10 vs. JBOD >> with ZFS mirrors to see if this makes a difference. > > The answer to this is "it depends". If the PCI-E and controller have enough > bandwidth capacity, then the write bottleneck will be the disk itself.
If you have HDDs, the write bandwidth bottleneck will be the disk. > If there is insufficient controller bandwidth capacity, then the controller > becomes the bottleneck. We don't tend to see this for HDDs, but SSDs can crush a controller and channel. -- richard _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
