Roedy Green <see_webs...@mindprod.com.invalid> writes: > On Fri, 5 Jun 2009 18:15:00 +0000 (UTC), Kaz Kylheku > <kkylh...@gmail.com> wrote, quoted or indirectly quoted someone who > said : > >>Even for problems where it appears trivial, there can be hidden >>issues, like false cache coherency communication where no actual >>sharing is taking place. Or locks that appear to have low contention and >>negligible performance impact on ``only'' 8 processors suddenly turn into >>bottlenecks. Then there is NUMA. A given address in memory may be >>RAM attached to the processor accessing it, or to another processor, >>with very different access costs. > > Could what you are saying be summed up by saying, "The more threads > you have the more important it is to keep your threads independent, > sharing as little data as possible."
Absolutely... not a new observation, either, as it follows directly from Amdahl's law. -- http://mail.python.org/mailman/listinfo/python-list