Re: gettimeofday resolution seriously degraded in test9

From: Chris Friesen (cfriesen_at_nortelnetworks.com)
Date: 10/30/03

  • Next message: bd: "Re: Post-halloween doc updates." 
    Date:	Thu, 30 Oct 2003 17:50:37 -0500
To: root@chaos.analogic.com

    Richard B. Johnson wrote:

    > There isn't any magic that can solve this problem. It turns out
    > that with later Intel CPUs, one can get CPU-clock resolution
    > from rdtsc. However, this is hardware-specific. If somebody
    > modifies the gettimeofday() and the POSIX clock routines to
    > use rdtsc when available, a lot of problems will go away.

    Its not just x86. PowerPC has a similar call, so does MIPS, and I'm
    sure most other modern cpus do too.

    The only problem with this stuff is that they usually slow down when the
    cpu does, so laptops and other power-managed chips cause complexities.

    Chris 

    -- 
Chris Friesen                    | MailStop: 043/33/F10
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  • Next message: bd: "Re: Post-halloween doc updates."

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