On Mon, Sep 27, 2004 at 03:55:48PM +0200, Pep Turr? wrote: > Hi, > > (this is a bit off-topic) > > On Wed, 22 Sep 2004 17:55:50 -0500, Pete Harlan <[EMAIL PROTECTED]> wrote: > > The Asus A8V I bought has both a VIA and a Promise SATA controller, > > and both work fine with Linux. The Promise is better supported under > > Linux (or possibly just a better controller; it does TCQ under Linux, > > where the VIA doesn't (yet?)) as far as I could tell from the SATA > > compatibility page. > > I was wondering: having both a Promise and a VIA SATA controllers and > 2 hard drives: to implement software raid, which of these > configurations would give better performance?: > > 1. One HD attached to a different controller (one to VIA, one to Promise) > 2. Both HDs on the VIA controller > 3. Both HDs on the Promise controller > > I guess that using a single controller would put more load on it but > reduce the PCI bus load, and vice versa... am I right?
Check your motherboard block diagram. If the disk controller is attached directly to the chipset, not through a 32bit/33MHz PCI bus, that's a Good Thing. If that's the case for only one of the controllers, you should obviously use that controller. (esp. don't use a controller that shares a slow bus with gigE if you're going to do any file/web-serving.) > >From the thread discussion, I would say that option 3 is better than 2 > (Promise being a better controller)... but is it better than option 1 > in overall performance on this scenario? what do you think? I agree. Hard drives these days don't saturate 150MB/s SATA, except on burst transfers to/from their cache. W/ 2 drives, you might come close to saturating 133MB/s 32bit 33MHz PCI. faster/wider PCI busses, hypertransport, or VIA's V-link (between north and southbridges) won't be a bottleneck unless you have more drives. -- #define X(x,y) x##y Peter Cordes ; e-mail: X([EMAIL PROTECTED] , des.ca) "The gods confound the man who first found out how to distinguish the hours! Confound him, too, who in this place set up a sundial, to cut and hack my day so wretchedly into small pieces!" -- Plautus, 200 BC
