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<DIV><FONT face=Arial size=2>Well, doubling the bandwidth is great of course,
but will it sell more machines?</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Important is the price a socket. I tend to remember
that the initial bare price of a node (12 sockets) is around 50000
dollar</FONT></DIV>
<DIV><FONT face=Arial size=2>and within 1 node you've got a one way pingpong
latency of 1.5 us from cpu to cpu.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>That's pretty expensive, considering that just the
bare machine itself without too much RAM and without too much i/o</FONT></DIV>
<DIV><FONT face=Arial size=2>already gets very expensive.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>A 2400 socket machine is soon then like 200 * 50k =
10 MLN dollar without additional network, without additional RAM</FONT></DIV>
<DIV><FONT face=Arial size=2>and with little i/o. </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So basically money talks too.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>50k for 12 socket node at a great
supercomputer isn't much, but you really want something then that is great
everywhere.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Further the latency within 1 node is not exactly
magnificent. The entire machine has a great latency from node to
node,</FONT></DIV>
<DIV><FONT face=Arial size=2>but majority of scientists in first place run
something at a cpu or 4-12 and want that application to perform fast. In
general</FONT></DIV>
<DIV><FONT face=Arial size=2>that application simply can't handle 1.5 us
latencies in such low number of cpu's.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>IMHO doubling the bandwidth is nice on paper, but
90% of the jobs are jobs of just a few processors, if *those* run
slow</FONT></DIV>
<DIV><FONT face=Arial size=2>then the machine simply doesn't get
bought.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>So theoretically spoken the improvement is great,
practical i doubt it will change decision taking.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>Vincent</FONT></DIV>
<BLOCKQUOTE
style="PADDING-RIGHT: 0px; PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #000000 2px solid; MARGIN-RIGHT: 0px">
<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=edkarns@firewirestuff.com href="mailto:edkarns@firewirestuff.com">Ed
Karns</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=beowulf@beowulf.org
href="mailto:beowulf@beowulf.org">beowulf@beowulf.org</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Monday, April 03, 2006 8:57
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> [Beowulf] Re: next gen /
parallel processing</DIV>
<DIV><FONT face=Arial size=2></FONT><FONT face=Arial size=2></FONT><FONT
face=Arial size=2></FONT><FONT face=Arial size=2></FONT><BR></DIV>"
... <FONT class=Apple-style-span face=Arial>the HyperTransport Consortium
is weeks away from launching HT 3.0, which is expected to at least double the
bandwidth of that interconnect while lowering latency and leaving the
underlying protocol largely unaltered. ..." From <FONT
class=Apple-style-span face="Lucida Grande"><A
href="http://www.eetimes.com/news/latest/showArticle.jhtml?articleID=181502574">http://www.eetimes.com/news/latest/showArticle.jhtml?articleID=181502574</A>
... article on Cray's latest efforts.</FONT></FONT>
<DIV><FONT face=Arial size=2></FONT><FONT face=Arial size=2></FONT><FONT
face=Arial size=2></FONT><FONT face=Arial size=2></FONT><BR
class=khtml-block-placeholder></DIV>
<DIV><FONT class=Apple-style-span face=Arial><FONT class=Apple-style-span
face="Lucida Grande">This next generation of parallel processing scenarios
appears dovetail nicely with the Beowulf concept. Anyone looking into
this? <BR></FONT></FONT>
<DIV></DIV><FONT class=Apple-style-span face=Arial><BR></FONT>
<DIV>
<P style="MARGIN: 0px; FONT: 13px Lucida Grande">Ed Karns</P>
<P
style="MARGIN: 0px; FONT: 13px Lucida Grande">FireWireStuff.com </P><BR
class=Apple-interchange-newline></DIV></DIV>
<P>
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