From owner-freebsd-current Fri Nov 29 23:14:17 2002 Delivered-To: freebsd-current@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id 2CA5237B401 for ; Fri, 29 Nov 2002 23:14:16 -0800 (PST) Received: from mailman.zeta.org.au (mailman.zeta.org.au [203.26.10.16]) by mx1.FreeBSD.org (Postfix) with ESMTP id 33C9C43EA9 for ; Fri, 29 Nov 2002 23:14:15 -0800 (PST) (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 SAA01093; Sat, 30 Nov 2002 18:12:05 +1100 Date: Sat, 30 Nov 2002 18:25:50 +1100 (EST) From: Bruce Evans X-X-Sender: bde@gamplex.bde.org To: David Syphers Cc: Kris Kennaway , Subject: Re: 5.0-DP2 questions In-Reply-To: <200211291304.47766.dsyphers@uchicago.edu> Message-ID: <20021130180108.F3539-100000@gamplex.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 Fri, 29 Nov 2002, David Syphers wrote: > On Friday 29 November 2002 12:12 pm, Kris Kennaway wrote: > > On Fri, Nov 29, 2002 at 12:11:42PM -0500, Robert Ames wrote: > > > > > 2. My machine is a Pentium 166 with only 16 MB of RAM. I'm trying > > > to rebuild the kernel and so far the compile has been running for > > > almost 24 hours and it's not finished yet. Is this to be expected? > > > > Yes. gcc 3.x is slower, and the kernel contains more code. Your > > machine is probably swapping a lot just doing the compilation, which > > will make it even slower. > > Out of curiosity, how much slower is a 5.x kernel compilation than a 4.x, on > average? I'm not sure about 4.x, but a -current kernel with no modules takes about 3 times as long as a RELENG_3 kernel compiled by the 4.x compiler used to take (about 130 seconds instead of 43 seconds on an Athlon 1600 overclocked. The kernels are supposed to have a similar set of options. All times are all times are after running "make depend" which takes about 8 seconds for RELENG_3 and 11 seconds for -current. gcc-3 in April 2002 pessimized the compile times from 76 seconds to 114 seconds for -current and from 43 seconds to 66 seconds for RELENG_3. Further development of -current pessimized the compile time from 114 seconds to 130 seconds. Compiling LINT took 437 seconds on Sep 22. IIRC, compiling modules takes about the same time as compiling LINT. > My 486, 66 MHz and 16 MB RAM, compiles a 4.x kernel in about 3 > hours. Thus by Robert's data point, -current seems at least 10-15 times > slower... Ouch. I remember being happy when upgrading from a 486/33 with 16MB to a 486DX2/66 with 32MB reduced my kernel compile time from about 16 minutes to about 9 minutes. Your 16MB of RAM is probably not nearly enough for today's bloat. Look at the real, user and system times and systat/vmstat/top to see if there is a lot of idle time caused by waiting for disks and/or paging to disk. Bruce To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-current" in the body of the message