Date: Tue, 31 Oct 1995 10:05:22 -0800 From: "Justin T. Gibbs" <gibbs@freefall.FreeBSD.org> To: "Garrett A. Wollman" <wollman@lcs.mit.edu> Cc: "Justin T. Gibbs" <gibbs@freefall.FreeBSD.org>, current@FreeBSD.org, wollman@FreeBSD.org Subject: Re: Time problems Message-ID: <199510311805.KAA08628@aslan.cdrom.com> In-Reply-To: Your message of "Tue, 31 Oct 1995 12:47:55 EST." <9510311747.AA29686@halloran-eldar.lcs.mit.edu>
next in thread | previous in thread | raw e-mail | index | archive | help
>If that doesn't work, then just #ifdef out the body of >the function, which will cause the 8254-alike to act as the reference >for timekeeping. Can we do occasional 8254 based sanity checking of the system time to either automatically revert to the 8254 on systems that the new code yields poor results, or simply to fix up the time occasionally? I thought the main reason for using this approach was to remove the overhead of going out to the 8254, so doing so only every once in a while gives the same type of reduction we have know, but should work on all systems that have a working 8254. >Needless to say, on the three different motherboards we have here >(60, 100, and 120-MHz CPUs), we have never seen this problem, so it's >a bit hard to diagnose. For those machines on which the results are >reasonable, I expect timekeeping to be rather better than it was. >According to xntpd, my machine is within about 3 seconds per day, >which is about the same as it was before. (It's the precision, rather >than the accuracy, where this technique gives a benefit.) > >-GAWollman Precision and overhead right? Why is it that xntpd doesn't either complain about my large offset (I started it just after using ntpdate), or keep my time in sync? >-- >Garrett A. Wollman | Shashish is simple, it's discreet, it's brief. ... >wollman@lcs.mit.edu | Shashish is the bonding of hearts in spite of distance. >Opinions not those of| It is a bond more powerful than absence. We like peopl >e >MIT, LCS, ANA, or NSA| who like Shashish. - Claude McKenzie + Florent Vollant -- Justin T. Gibbs =========================================== Software Developer - Walnut Creek CDROM FreeBSD: Turning PCs into workstations ===========================================
Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?199510311805.KAA08628>