Changes between Initial Version and Version 1 of Ticket #1993


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Timestamp:
Mar 31, 2008, 5:53:19 AM (16 years ago)
Author:
axeld
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  • Ticket #1993 – Description

    initial v1  
    11On CPUs that are able to change their frequency, the TSC increment is not invariant. Therefore, we cannot use it to compute time on these machines. Unfortunately, most recent CPUs are affected due to power saving features.
     2
     3Furthermore, in a SMP environment, the TSC of the different CPUs can drift apart. See http://lkml.org/lkml/2005/11/4/173 for an interesting insight on that topic.
     4
     5For HPET (and PM timer) see ACPI 3.0 specification: http://www.acpi.info/spec.htm