lkml.org 
[lkml]   [2003]   [Apr]   [22]   [last100]   RSS Feed
Views: [more markup]  [less markup]  [headers]  [forward] 
 
Messages in this thread
/
SubjectRe: several messages
DateTue, 22 Apr 2003 16:38:15 -0700
FromRick Lindsley <>
    Have you done any tests with a threaded process running on a single CPU in
    the siblings? If they are sharing data and locks in the same cache it's
    not obvious (to me at least) that it would be faster in two CPUs having to
    do updates. That's a question, not an implication that it is significantly
    better in just one, a threaded program with only two threads is not as
    likely to be doing the same thing in both, perhaps.

True.  I have a hunch (and it's only a hunch -- no hard data!) that
two threads that are sharing the same data will do better if they can
be located on a physical/sibling processor group.  For workloads where
you really do have two distinct processes, or even threads but which are
operating on wholly different portions of data or code, moving them to
separate physical processors may be warranted.  The key is whether the
work of one sibling is destroying the cache of another.

Rick
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@vger.kernel.org
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/

\
 
 \ /
  Last update: 2005-03-22 12:34    [W:0.164 / U:0.200 seconds]
©2003-2008 Jasper Spaans