Skip site navigation (1)Skip section navigation (2)
Date:      Thu, 23 Jul 1998 14:01:38 +1000
From:      Bruce Evans <bde@zeta.org.au>
To:        bde@zeta.org.au, phk@critter.freebsd.dk
Cc:        brian@Awfulhak.org, freebsd-current@FreeBSD.ORG, jak@cetlink.net
Subject:   Re: tickadj -t not changing tick
Message-ID:  <199807230401.OAA09064@godzilla.zeta.org.au>

next in thread | raw e-mail | index | archive | help
>>The whole problem may be caused by APM.  APM's time handling is of low
>>quality.
>
>As currently designed, there is only the RTC chip which is reliably keeping
>track of time on a APMized system, and only reading the registers is reliable,
>the number of interrupts and their frequency is subject to change without
>notice.

The RTC is sufficiently reliable.  One reason that APM's time handling is
of low quality because it doesn't sync with the RTC; it just reads it.
Another reason is that it doesn't honour the current spl; it uses
splsoftclock() to force the ipl to the level for timeout routines.
This may be just a no-op if suspend/resume are always called as timeout
routines.

My version of inittodr() syncs with the RTC.  This takes a second or two.
The delay would be bad if suspension intervals are short enough for the
innaccurate reading of the RTC to casue negative times.

Bruce

To Unsubscribe: send mail to majordomo@FreeBSD.org
with "unsubscribe freebsd-current" in the body of the message



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199807230401.OAA09064>