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<DIV><FONT face=Arial size=2>good all mighty </FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV>"AI39. Cache Data Access Request from One Core Hitting a Modified Line
in<BR>the L1 Data Cache of the Other Core May Cause Unpredictable
System<BR>Behavior<BR>When request for data from Core 1 results in a L1 cache
miss, the request is<BR>Problem:<BR>sent to the L2 cache. If this request hits a
modified line in the L1 data cache<BR>of Core 2, certain internal conditions may
cause incorrect data to be returned<BR>to the Core 1."</DIV>
<DIV> </DIV>
<DIV><FONT face=Arial size=2>with such a hardware bug you just can't garantuee
parallel correctness.</FONT></DIV>
<DIV><FONT face=Arial size=2>my entire parallellism is based upon
this.</FONT></DIV>
<DIV><FONT face=Arial size=2></FONT> </DIV>
<DIV><FONT face=Arial size=2>hope they fix that chip and ship around new ones to
customers. </FONT></DIV>
<DIV><FONT face=Arial size=2>no bios is gonna fix such a cache bug of
course.</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=johannesrs@gmail.com href="mailto:johannesrs@gmail.com">Jones de
Andrade</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Cc:</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, November 13, 2006 11:37
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [Beowulf] Core 2 Duo Bugs:
Any importance in the beowulf field?</DIV>
<DIV><BR></DIV>Hi!<BR><BR>Thanks a lot for the answer.<BR><BR>Anyway, I would
like to go a bit deeper on this subject. I know that there are this kind of
problems in every processor. I know that the number 39 is the one of real
concer. But we also know that still it seems to NOT have a fix, work around ou
bios update for it. So I would like to know if this is of real concern in the
field of clustering and beowulfs, and what are the impressions people are
having on these processors (and what kind of "way-around" is being used).
<BR><BR>Thanks a lot in advance for everything,<BR><BR>Sincerally
yours,<BR><BR>Jones<BR><BR>
<DIV><SPAN class=gmail_quote>On 11/11/06, <B class=gmail_sendername>Douglas
Eadline</B> <<A href="mailto:deadline@clustermonkey.net">
deadline@clustermonkey.net</A>> wrote:</SPAN>
<BLOCKQUOTE class=gmail_quote
style="PADDING-LEFT: 1ex; MARGIN: 0pt 0pt 0pt 0.8ex; BORDER-LEFT: rgb(204,204,204) 1px solid"><BR>Generally
these issues are handled by compilers, BIOS, microcode <BR>updates, and
steppings of the processor. All new processors have<BR>a list of bugs. The
AI 39 seems to be of some concern.<BR><BR>Check this document,<BR><BR><A
href="http://www.intel.com/design/processor/specupdt/313279.htm">http://www.intel.com/design/processor/specupdt/313279.htm</A><BR><BR>Again,
don't be alarmed this is standard for all
processors.<BR><BR>--<BR>Doug<BR><BR><BR><BR>> Hi all.<BR>><BR>>
Wel, let me go straigh to the point: I'm a begginer, more or less <BR>>
enthusiastic about the beowulf world. I've been keeping track of this
list<BR>> for a good time.<BR>><BR>> I would like to aks just one
single (and probably stupid) question: A few<BR>> months ago, Intel
released a small list of bugs of the first version of <BR>> the<BR>>
Core 2 chips family. Much discussion has gone around the web about
whether<BR>> or not these bugs (or some, or any of them) would affect any
class of<BR>> users.<BR>><BR>> I haven't seen such a discussion
here. I would like to know if there <BR>> aren't<BR>> any concerns on
using this chips in the kind ofapplication beowulfs are<BR>> usually
used? Specially for scientific applications?<BR>><BR>> And what's the
experience anyone got with those chips? Good, bad... <BR>><BR>> Thanks
a lot in advance, and sorry for wasting your tie,<BR>><BR>> Sincerally
yours,<BR>><BR>> Jones<BR>>
_______________________________________________<BR>> Beowulf mailing
list, <A href="mailto:Beowulf@beowulf.org">Beowulf@beowulf.org</A><BR>>
To change your subscription (digest mode or unsubscribe) visit<BR>> <A
href="http://www.beowulf.org/mailman/listinfo/beowulf">http://www.beowulf.org/mailman/listinfo/beowulf</A><BR>><BR><BR><BR>--<BR>Doug<BR></BLOCKQUOTE></DIV><BR>
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