From owner-freebsd-current Sat Aug 25 23: 8:14 2001 Delivered-To: freebsd-current@freebsd.org Received: from mailman.zeta.org.au (mailman.zeta.org.au [203.26.10.16]) by hub.freebsd.org (Postfix) with ESMTP id A12BF37B401; Sat, 25 Aug 2001 23:08:10 -0700 (PDT) (envelope-from bde@zeta.org.au) Received: from bde.zeta.org.au (bde.zeta.org.au [203.2.228.102]) by mailman.zeta.org.au (8.9.3/8.8.7) with ESMTP id QAA28229; Sun, 26 Aug 2001 16:07:07 +1000 Date: Sun, 26 Aug 2001 16:06:57 +1000 (EST) From: Bruce Evans X-X-Sender: To: Mike Smith Cc: Thierry Herbelot , David Hill , , Subject: Re: options HZ [MFC for pr=28143] In-Reply-To: <200108260115.f7Q1FNn22234@mass.dis.org> Message-ID: <20010826155534.E15196-100000@besplex.bde.org> MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-current@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On Sat, 25 Aug 2001, Mike Smith wrote: > It should be a tunable, not a compile-time option. > > > David Hill wrote: > > > > > > Hello - > > > Could someone please document "options HZ" into LINT?. I found it whil > > e > > > reading the dummynet(4) manpage. It must remain a compile-time option for those of us who don't believe in tunables. Notes: - Making HZ non-constant (almost everything uses `hz' instead of HZ) mainly pessimizes time-critical code that computes hz/CONST, except: - on alphas, the HZ option has no effect. The initial value of hz = HZ is not used except to compute wrong values for `tick' and `tickadj' (`tick' is fixed up later but `tickadj' remains wrong). `hz' is initialized to hwprb->rpb_intr_freq >> 12 in alpha/machdep.c. So, hz needs to be non-constant and the HZ option and tunables just get in the way for alphas and for other arches where the hardclock frequency is not programmable. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message