Re: Fwd: [GIT PULL] timer changes for v3.10

From: Ingo Molnar
Date: Thu May 09 2013 - 04:59:11 EST



* Pavel Machek <pavel@xxxxxx> wrote:

> [I still wonder how adjtime is going to work in TSC(runtime)+RTC(s2disk)
> case; surely TSC has different drift than RTC, and so adjtime will have
> fun trying to estimate the drift... but that's not new problem and not
> affected by that patch.]

NTP, once it has settled, typically deals with millisecond, microsecond
level adjustments.

The RTC has a basic granularity of 1 second - so s2ram is a ~500 msecs
kick in the guts for NTP and drift is the least of the problems.

On future systems it won't matter, as the TSC will be used for everything
that does not completely power off the system, as Thomas explained it.

Thanks,

Ingo
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