Re: TSC instead of ACPI: powerd doesn't work anymore (to be expected?)

From: David O'Brien (obrien_at_freebsd.org)
Date: 10/30/05

  • Next message: Bjoern A. Zeeb: "LOR on kldunload nve/radix node head (v6?)" 
    Date: Sun, 30 Oct 2005 01:37:18 -0800
To: David Xu <davidxu@freebsd.org>

    On Sun, Oct 30, 2005 at 02:39:40PM +0800, David Xu wrote:
    > David O'Brien wrote:
    > >On Fri, Oct 28, 2005 at 03:34:57PM +0200, Alexander Leidinger wrote:
    > >>I don't have the message at hand. I just had time to write the mail, but I
    > >>don't have my laptop with me to reproduce the message. But it's easy to
    > >>reproduce, just take a PC which is able to make use of powerd and switch
    > >>to
    > >>using TSC as the timecounter.
    > >
    > >What is the motivation to use the TSC as a timecounter?
    >
    > TSC is faster than any others, on many systems, so-called ACPI-fast
    > timer is really a slow chip,

    Correct, but why is it felt the latency of the ACPI timer is an issue?
    Of course we all want things to as fast as possible, but is that just an
    abstract desire, or a real issue was run into? 

    -- 
-- David  (obrien@FreeBSD.org)
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