Tim wrote: > > > On Tue, Sep 30, 2008 at 7:15 PM, David Magda <[EMAIL PROTECTED] > <mailto:[EMAIL PROTECTED]>> wrote: > > On Sep 30, 2008, at 19:09, Tim wrote: > > SAS has far greater performance, and if your workload is > extremely random, > will have a longer MTBF. SATA drives suffer badly on random > workloads. > > > Well, if you can probably afford more SATA drives for the purchase > price, you can put them in a striped-mirror set up, and that may > help things. If your disks are cheap you can afford to buy more of > them (space, heat, and power not withstanding). > > > More disks will not solve SATA's problem. I run into this on a daily > basis working on enterprise storage. If it's for just > archive/storage, or even sequential streaming, it shouldn't be a big > deal. If it's random workload, there's pretty much nothing you can do > to get around it short of more front-end cache and intelligence which > is simply a band-aid, not a fix.
I observe that there are no disk vendors supplying SATA disks with speed > 7,200 rpm. It is no wonder that a 10k rpm disk outperforms a 7,200 rpm disk for random workloads. I'll attribute this to intentional market segmentation by the industry rather than a deficiency in the transfer protocol (SATA). -- richard _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
