Just fwiw, as something of an outsider, I wasn't able to meaningfully parse this exchange.<br>
Peter<br><br><div><span class="gmail_quote">On 5/19/08, <b class="gmail_sendername">Jeffrey B. Layton</b> <<a href="mailto:laytonjb@charter.net">laytonjb@charter.net</a>> wrote:</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
Perry E. Metzger wrote:<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><span class="q">
"Jeffrey B. Layton" <<a href="mailto:laytonjb@charter.net" target="_blank" onclick="return top.js.OpenExtLink(window,event,this)">laytonjb@charter.net</a>> writes<br>
</span><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
In any case, let me note the most important rule: if your CPUs aren't<span class="q"><br>
doing work most of the time, you're not allocating resources<br>
properly. If the task is really I/O bound, there is no point in having<br>
more CPU than I/O can possibly manage. You're better off having 1/2th<br>
the number of nodes with gargantuan amounts of cache memory than<br>
having CPUs that are spending 80% of their time twiddling their<br>
thumbs. The goal is to have the CPUs crunching 100% of the time, and<br>
if they're not doing that, you're not doing things as well as you can.<br>
<br>
</span></blockquote>
I absolutely disagree.<br>
<br>
</blockquote><span class="q">
<br>
Chacun a son gout. I was under the impression that in scientific<br>
computing the name of the game was having your computation done as<br>
fast as possible at the lowest possible cost.<br>
<br>
If your CPU is idle, why did you pay for it? They're a huge cost<br>
differential these days between fast and slow CPUs. Why didn't you buy<br>
a much cheaper CPU that would remain nearly 100% busy while keeping<br>
the I/O subsystem as fast? You would have saved lots of cash, your job<br>
would be done just as fast, and probably (in a modern system) you<br>
would have saved a whole lot of electricity because slower CPUs eat<br>
fewer Watts.<br>
<br>
</span></blockquote>
<br>
Evidently you don't know jack about real codes. In addition, I've gotten<br>
some off-list messages that you have already been added to a number of<br>
kill files as a troll because of you inability to listen, understand, and explain,<br>
plus your off-list obnoxious emails. I've joined the gang in adding you to my<br>
kill file. Enjoy.<span class="q"><br>
<br>
<br>
<blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;"><blockquote class="gmail_quote" style="border-left: 1px solid rgb(204, 204, 204); margin: 0pt 0pt 0pt 0.8ex; padding-left: 1ex;">
I believe you're thinking of local IO - like a desktop.<br>
<br>
</blockquote>
<br>
No, really, I'm not.<br>
<br>
</blockquote>
<br></span>
B.S.<br>
<br>
Jeff<div><span class="e" id="q_11a0224cfb882fd7_9"><br>
<br>
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