Messages in this thread | | | Date | Thu, 11 Nov 2004 21:52:27 -0800 (PST) | From | dean gaudet <> | Subject | CONFIG_X86_PM_TIMER is slow |
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when using CONFIG_X86_PM_TIMER i'm finding that gettimeofday() calls take 2.8us on a p-m 1.4GHz box... which is an order of magnitude slower than TSC-based solutions.
on one workload i'm seeing a 7% perf improvement by booting "acpi=off" to force it to use tsc instead of the PM timer... (the workload calls gettimeofday too frequently, but i can't change that).
i'm curious why other folks haven't run into this -- is it because most systems have HPET timer as well and that's not nearly as bad as PM timer?
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