On Mon, Mar 28, 2005 at 11:35:37PM +0200, shimi wrote: > > --=-iuQFSqE5IfCkytOwtoW6 > Content-Type: text/plain > Content-Transfer-Encoding: 7bit > > On Mon, 2005-03-28 at 23:11 +0200, Ilya Konstantinov wrote: > > > shimi wrote: > > > > > After looking up in Tyan's site, and looking in the specs of the MB > > > (URL: http://www.tyan.com/products/html/tigerk8w_spec.html > > > <http://www.tyan.com/products/html/tigerk8w_spec.html%29,> ), I saw > > > that it contains "Silicon Image Sil3114 SATA Raid Accelerator". > > > > > > I contacted the store I am planning on buying the machine from, and > > > asked them wether it's well supported in Linux. I got a weird answer > > > that "the SATA will work, but you'll have to do the RAID-1 you're > > > planning to do by software..." > > > > > Sounds like a pretty sensible answer.
I would say more - it says very good things about this store. I am yet to have such an experience myself. [snip] > 2. I don't need to control the Hardware RAID from within Linux, as I'll > not be building/removing volumes etc on the live system... (however > reading errors from the controller would be nice). I was surprised about > the fact "the SATA works, but RAID [completely. not only management] > will not". I had the impression that when you do a RAID with hardware > running it, it appears to the OS as one single device (/dev/sda, > probably), and the OS doesn't even KNOW that the drive is mirrored... > (that's how it was for me in the past with an Adaptec doing RAID-5 on > SCSI drives, it just appeared as /dev/sda. But that was native-SCSI, and > maybe SATA is different. I don't know. :)). Are you sure it's hardware raid? I am pretty sure it's not, it's software raid done by the driver. I never used Silicon Image raid, but did use their SATA. Not this chip, though - only SiI3112. And still not with 2.6/libata. Works well. > > Hope to get clarifications, and more importantly, success stories! :) I would personally not use its raid even if it exists and works well. The only advantage you get over native linux software raid (probably md, but other options exist) is that you keep the configuration in an OS- independant way, which allows easily dual-booting over this raid. Not useful for a server. That is, unless they added some very fancy stuff to their driver. But it's still just software. The spec you sent also says "Connected to legacy 32-bit 33MHz PCI bus". I don't know what it means, but you might get better performance by connecting one disk as SATA and one as PATA (which means non-identical disks). At least I did. On some older hardware, but I would check this also today. It was on this machine (don't recall exact board model, but it's a dual xeon 2.4Ghz, 2GB RAM and this sii3112), with two 120GB disks. They were both pata, but were bought with sata convertors. So I could connect them as I wanted, and also knew they are exactly the same (in terms of same partition tables, etc.). They both gave me, when working alone, both though the sii and the ICH4, 55MB/s. When both were through sii, I only got 44MB/s. When one through sii and one through ich4, 55MB - no loss at all. When both through ich4, only 32MB/s. Which means the sii was faster than the ich4, but still not fast enough to handle both disks. If you do make some measurements, I would love to hear your results. All of this, BTW, was with zcav on the disks themselves. I did not measure md raid1 write speed (reading is only from one disk anyway). -- Didi ================================================================= To unsubscribe, send mail to [EMAIL PROTECTED] with the word "unsubscribe" in the message body, e.g., run the command echo unsubscribe | mail [EMAIL PROTECTED]
