Messages in this thread |  | | Date | Sat, 29 Sep 2001 01:37:46 +0100 | From | Jonathan Morton <> | Subject | RE: CPU frequency shifting "problems" |
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> > APM is a lost cause, but the correct solution for ACPI systems is >to use the >> PM timer. > >This is _completely_ untrue. > >The PM timer is (a) inaccurate and (b) slow as hell. > >Linux uses TSC because we want high accuracy (nanosecond scale) without >having slow stuff.
Please, don't confuse accuracy with precision. The TSC is precise but not accurate. The 100Hz timer is more accurate, especially given a SpeedStep CPU, but much less precise. It's a subtle distinction, but an important one.
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