Date: Fri, 26 Oct 2001 14:34:48 -0700 (PDT) From: John Baldwin <jhb@FreeBSD.org> To: Matthew Dillon <dillon@apollo.backplane.com> Cc: Poul-Henning Kamp <phk@critter.freebsd.dk>, arch@FreeBSD.ORG, Peter Wemm <peter@wemm.org>, Bakul Shah <bakul@bitblocks.com> Subject: Re: 64 bit times revisited.. Message-ID: <XFMail.011026143448.jhb@FreeBSD.org> In-Reply-To: <200110262128.f9QLSX838762@apollo.backplane.com>
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On 26-Oct-01 Matthew Dillon wrote: > >:>::so far for the in-kernel time keeping, IMO. >:> >:> And I will also note that trying to represent both seconds and >:> sub-seconds >:> in a single fixed point integer is a real bad idea. It makes life >:> unnecessarily difficult for the 95% of the code that only needs the >:> seconds portion. Any fractional representation should be a SEPARATE >:> field. >: >:Err it is a separate field. You have a 128-bit counter. The high 64-bits >:are >:the seconds portion. You just shift to get the seconds. This is not hard. >:Computers have been good at doing shift right's for quite some time now. >: >:-- >: >:John Baldwin <jhb@FreeBSD.org> -- http://www.FreeBSD.org/~jhb/ > > The phrase 'no freaking way' comes to mind. > > You guys are outsmarting yourselves. Seconds, ok. That's it. Nothing > else. The *VAST* majority of programs only need seconds, it would be > utterly stupid to require that they mess around with some weird fixed > point quantity when all they want is seconds, no matter how supposedly > 'simple' that messing around is (i.e. '>> 64' is not acceptable). > > -Matt Umm. Dude, this is for the kernel's internal representations. We can massage it in libc or in the kernel before it gets to userland. We do have to maintain compatibility. Slow down and think about this for a second. -- John Baldwin <jhb@FreeBSD.org> -- http://www.FreeBSD.org/~jhb/ PGP Key: http://www.baldwin.cx/~john/pgpkey.asc "Power Users Use the Power to Serve!" - http://www.FreeBSD.org/ To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-arch" in the body of the message
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