> -----Original Message----- > From: linux-raid-owner@xxxxxxxxxxxxxxx [mailto:linux-raid- > owner@xxxxxxxxxxxxxxx] On Behalf Of Ming Zhang > Sent: Wednesday, June 22, 2005 8:49 PM > To: bdameron@xxxxxxxxxxxxx > Cc: linux-raid@xxxxxxxxxxxxxxx > Subject: Re: More tales of horror from the linux (HW) raid crypt > > On Wed, 2005-06-22 at 17:14 -0700, bdameron@xxxxxxxxxxxxx wrote: > > Quoting Ming Zhang <mingz@xxxxxxxxxxx>: > > > > > will this 24 port card itself will be a bottleneck? > > > > > > ming > > > > Since the card is PCI-X the only bottleneck on it might be the Processor > since > > it is shared with all 24 ports. But I do not know for sure without > testing it. > > I personally am going to stick with the new 16 port version. Which is a > PCI- > > Express card and has twice the CPU power. Since there are so many > spindles it > > should be pretty darn fast. And remember that even tho the drives are > 150MBps > > they realistically only do about 25-30MBps. > > the problem here is taht each HD can stably deliver 25-30MBps while the > PCI-x will not arrive that high if have 16 or 24 ports. i do not have a > chance to try out though. those bus at most arrive 70-80% the claimed > peak # :P Maybe my math is wrong... But 24 disks at 30 MB/s is 720 MB/s, that is about 68.2% of the PCI-X bandwidth of 1056 MB/s. Also, 30 MB/s assumes sequential disk access. That does not occur in the real world. Only during testing. IMO Guy > > > > > > > Brad Dameron > > SeaTab Software > > www.seatab.com > > - > > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > > the body of a message to majordomo@xxxxxxxxxxxxxxx > > More majordomo info at http://vger.kernel.org/majordomo-info.html - To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
