Re: clock works slowly when I change CPU speed

I changed 3 files in quoted mail below (tsc.c  clock.h  clock.c)
back to the previous revision, 
on my ThinkPad A22e (the last cvsup was on Aug 13), 
and recompiled kernel (the config file is almost the same as GENERIC), 
and compared behavior of the clock between 2 kernels as:

    kernel with the latest (on Aug 13) revision of these 3 files
    kernel with the previous revision of these 3 file

On condition of hw.acpi.cpu.performance_speed as 8, 
the clock works
    normally ... for both of the latest and the previous revision
                 of these 3 files

On condition of hw.acpi.cpu.performance_speed as 4, 
the clock works
    slowly  ... for the latest revision of these 3 files
    normally ... for the previous revision of these 3 files

In details, when the clock works slowly, 
the clock works at the half of normal speed. 

For comparing clock, 
I used /usr/bin/top and another machine that has a reliable clock. 
                                              (ex. video recorder)
/bin/date is also suitable for comparing. 

On condition of the clock working slowly, 
snd_ich.ko said double of normal value for link rate (48000Hz is expected)
when I execute "kldload snd_ich" by hand. 


I read the diff between the revisions, 
but I could not find out reason why the change of 3 files affects
relations between clock and CPU speed setting. 
But it does affect. 


 On Fri, 15 Aug 2003 07:24:59 +0900 (JST) MATOBA Hirozumi wrote:
|  On Thu, 2003-08-14 at 19:50, Nate Lawson wrote:
| > This indicates that the problem was introduced in a kernel change between
| > Aug 2 and Aug 9 and that acpi is not at fault.  Try searching the cvs-all
| > archives between those dates (and perhaps narrowing the date more).
| 
| I misunderstood Nate Lawson's words at the first time I read, 
| but he said about the cvs-all *mailing-list* archive. 
| And I found the mail about keyword "clock" in it. 
| 
| I will try going back to before this change (by using cvsup etc). 
| 
| >> Message-Id: <200308061505.h76F5Sih048392_at_repoman.freebsd.org>
| >> From: Poul-Henning Kamp <phk_at_FreeBSD.org>
| >> Date: Wed, 6 Aug 2003 08:05:28 -0700 (PDT)
| >> To: src-committers_at_FreeBSD.org, cvs-src_at_FreeBSD.org,
| >>         cvs-all_at_FreeBSD.org
| >> X-FreeBSD-CVS-Branch: HEAD
| >> Subject: cvs commit: src/sys/i386/i386 tsc.c src/sys/i386/include clock.h
| >>  src/sys/i386/isa clock.c
| >> 
| >> phk         2003/08/06 08:05:28 PDT
| >> 
| >>   FreeBSD src repository
| >> 
| >>   Modified files:
| >>     sys/i386/i386        tsc.c 
| >>     sys/i386/include     clock.h 
| >>     sys/i386/isa         clock.c 
| >>   Log:
| >>   Dont initialize a TSC timecounter until we know if it is broken or not.
| >>   
| >>   Revision  Changes    Path
| >>   1.201     +6 -0      src/sys/i386/i386/tsc.c
| >>   1.45      +1 -0      src/sys/i386/include/clock.h
| >>   1.201     +1 -0      src/sys/i386/isa/clock.c

-- 
matoba_at_st.rim.or.jp