Greg Freemyer wrote:
I'm most interested in the sequential vs. random i/o nature of your workload. There is a huge difference in throughput. It can be as big as 10x just on that one question.
Since you say you are working with large files, I'll assume sequential.
Yep, very much sequential.
The fastest individual sata drives I've seen deliver speeds approaching 100MB/sec (or 1 Gbit/sec) while doing pure sequential access.
So you seem to be hoping to achieve 1.6 GB/sec (16 Gbit/sec). That is really pushing the limits and you are going to have to very carefully select your components.
Something along those lines, yes. There is a price/performance balance to be struck somewhere of course.
That should not be a problem for the "northbridge". Unfortunately most PCIexpress controllers hang of the "southbridge". I think you will find few if any southbridges that can run at 1.6 GB/sec. on the Northbridge / southbridge interconnect.
If you do, then you have to look at the southbridge to PCIexpress bus. I'd guess you will need multiple of those buses in order to cumulatively handle 1.6 GB/sec.
I think some very high-end motherboards have multiple independent PCIexpress buses in order to handle this sort of thing. I believe that is what you will need.
Thanks, I'll have to check that out. I've not yet looked at any board in detail, although I did see one or two with one PCIe x16 slot that got "split" into two PCIe x8 with two cards plugged in.
At the end of the day, if your serious about building something like this up you are going to have to start reading detailed throughput / bus specs. And once you do I'd post directly on the kernel ide mailing list to ask questions. They occasionally host discussions of very high performance systems, although I don't recall anything attempting to get 1.6 GB/sec out of the disk subsystem.
Ok, thanks. DIdn't even know there was such a list. /Per -- Per Jessen, Zürich (-1.9°C) -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org