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Re: (ITS#5668) Invalid entryCSN generated, and slapd will not restart



Hallvard B Furuseth wrote:
> Looking at liblutil/utils.c:lutil_gettime() led me to
>
>     Beware of QueryPerformanceCounter()
>     http://www.virtualdub.org/blog/pivot/entry.php?id=106
>
> Is warning relevant to slapd?  I don't know Windows programming at all.
>
Yes, it's relevant. People running on Windows should probably boot with 
/usepmtimer to make sure the ACPI timer is used (which runs at 3.5MHz). Then 
again, the simplest solution is "don't run mission-critical servers on 
Windows" because the platform is so completely inadequate, for this and many 
other reasons. Probably should read this as well
http://support.microsoft.com/kb/895980

Of course, not all of this uncertainty is Microsoft's fault - AMD documented 
that their dual-core processors would keep their TSCs in sync between both 
cores, but in reality the TSCs never stay in sync. So if you happen to be 
running an old-enough Windows release, written when the TSC was still believed 
to be a reliable clock source, you may have problems unless you explicitly 
tell Windows to use the ACPI PM timer.

If you're running on a very old motherboard that doesn't support ACPI, you 
won't have a PM timer to use; but in that case you're probably also running 
with a processor that doesn't have TSC issues.
-- 
   -- Howard Chu
   CTO, Symas Corp.           http://www.symas.com
   Director, Highland Sun     http://highlandsun.com/hyc/
   Chief Architect, OpenLDAP  http://www.openldap.org/project/