Re: Timer updates revision 7 (asm sets predicates/various fixes)

From: David Mosberger <>
Date: 2004-08-02 19:36:17
>>>>> On Fri, 30 Jul 2004 08:34:56 -0700 (PDT), Christoph Lameter <> said:

  >> The numbers above indicate a substantial slowdown going from 1 to
  >> 2 cpus. What happens at higher cpu counts.

  Christoph> The code that uses cmpxchg will always be a scalability
  Christoph> issue.

Also, you need to keep things in perspective: the test programs
_continually_ bangs on gettimeofday().  If the cmpxchg were a
scalability issue for, say, 16-32-way machines with _real_ workloads,
I'd really be surprised.  Now if you have 128 or more CPUs, I do agree
that the picture would be very different and scalability is a much
bigger concern.

To unsubscribe from this list: send the line "unsubscribe linux-ia64" in
the body of a message to
More majordomo info at
Received on Mon Aug 2 05:36:29 2004

This archive was generated by hypermail 2.1.8 : 2005-08-02 09:20:29 EST