<html><head></head><body style="word-wrap: break-word; -webkit-nbsp-mode: space; -webkit-line-break: after-white-space; ">Thanks for the link. I did the tests on an SGI SMP machine that, if I understand correctly, shares the memory much better than most other systems. I will read about these different components and see what I can figure out.<div><br></div><div>Thanks,</div><div>Francis</div><div><br><div><blockquote type="cite"><div><br> You need to understand the issues of memory bandwidth shared between cores and between processors, memory affinity and thread affinity ("binding") see <a href="http://www.mcs.anl.gov/petsc/documentation/faq.html#computers">http://www.mcs.anl.gov/petsc/documentation/faq.html#computers</a><br><br> Barry<br><font class="Apple-style-span" color="#006312"><br></font></div></blockquote></div><br></div></body></html>