Re: gettimeofday resolution seriously degraded in test9

From: Chris Friesen
Date: Thu Oct 30 2003 - 18:01:28 EST


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

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