From owner-freebsd-hackers Fri Nov 3 20:49:51 2000 Delivered-To: freebsd-hackers@freebsd.org Received: from peach.ocn.ne.jp (peach.ocn.ne.jp [210.145.254.87]) by hub.freebsd.org (Postfix) with ESMTP id 5260237B4C5 for ; Fri, 3 Nov 2000 20:49:49 -0800 (PST) Received: from newsguy.com (p03-dn03kiryunisiki.gunma.ocn.ne.jp [210.232.224.132]) by peach.ocn.ne.jp (8.9.1a/OCN/) with ESMTP id NAA25298; Sat, 4 Nov 2000 13:46:53 +0900 (JST) Message-ID: <3A039460.15D4C593@newsguy.com> Date: Sat, 04 Nov 2000 13:45:20 +0900 From: "Daniel C. Sobral" X-Mailer: Mozilla 4.7 [en] (Win98; I) X-Accept-Language: en,pt-BR MIME-Version: 1.0 To: Poul-Henning Kamp Cc: Joerg Micheel , Zhiui Zhang , freebsd-hackers@FreeBSD.ORG Subject: Re: granularity of gettimeofday() References: <2017.973277815@critter> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG Poul-Henning Kamp wrote: > > But the two *really* interesting things about the FreeBSD code is: > > You can change your timecounter on the fly. This allows > the machine to boot using maybe the TSC, then load the > bitcode on the xrpu board, initialize the hardware on the > xrpu and start to use that as the timecounter. > > If the hardware can be read atomically, no interrupt > locking is used. This means on a multi-CPU system you > will not have block interrupts to figure out what time > it is, in fact all CPUs can find out what time it is > *at the same time*, without interferring with each other. > > I belive those two features are unique to FreeBSD at this time. We need to write benchmarks that place heavy emphasis on these features, then. :-) -- Daniel C. Sobral (8-DCS) dcs@newsguy.com dcs@freebsd.org capo@world.wide.bsdconspiracy.net He has been convicted of criminal possession of a clue with intent to distribute. To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message