Fedora SMP dual core, dual AMD 64 processor system

[Bryan J. Smith]

On Wed, 2005-08-24 at 10:33 -0400, Mark Hahn wrote:
> actually I have.  it works OK, not fast, but stable.

Please detail?

Other than the mistake they did of backporting RAID-5 to the 6000 series
(it was never designed for it, only the 7000+), I've had 0 issues.  The
5000/6000 series were designed for RAID-0/1 and most excellent.  The
7000/8000 series of the last 5 years has been rock solid.  The new 9000
series has only had a few performance bugs, but the 9.1.x firmware works
most excellent for many, and has since shortly after it came out.

And I've been able to take my volumes from the 5000 up to any new
series.  I've had *0* volume incompatibility over 7 years.

> OK, show me the numbers.  show me the 12 GB/s memory interface on your 
> XScale card, show me the r5 engine that can run at 8 GB/s.

Do you even understand what you are talking about?
I/O Processors have different interconnect meshes than CPUs.
You want to talk about DTRs over _single_ points.

And, furthermore, where do you get 12GBps memory interface?
Socket-940 only has 6.4GBps, maximum.

And as far as XOR, the problem isn't the CPU time.  It's the fact that
you're first pushing every single piece of data in a write through the
CPU.

> certainly possible, but I don't think they exist.  and if they did, who
> would use  them?  even high-end scsi raid cards with multiple channels
> and BB-cache seem to run at only a couple hundred MB/s.  and there
> aren't really that  many systems that can sustain that kind of
> throughput.  (I have a $9M cluster arriving next month that will
> sustain about 3 GB/s - 12 object storage servers over quadrics...)

Talk about cost!  Dude, are we even on the same wavelength?

If you have dedicated systems doing your software RAID _separate_ from
your user services, then yes, software RAID _does_ work well!  But then
you're talking 2x system cost!

Don't call me out on cost if you're introducing segmented end-storage
and end-systems!  ;->

> ah, no wonder.  I had the feeling you were actually pining away for something
> other than linux - this used to happen a lot with *BSDers slumming on linux
> lists.

Oh get off it.  Bigot.


-- 
Bryan J. Smith     b.j.smith at ieee.org     http://thebs413.blogspot.com
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