From owner-freebsd-hackers Thu Feb 18 12:18:51 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from alpo.whistle.com (alpo.whistle.com [207.76.204.38]) by hub.freebsd.org (Postfix) with ESMTP id 9D06E113B8 for ; Thu, 18 Feb 1999 12:16:07 -0800 (PST) (envelope-from julian@whistle.com) Received: (from daemon@localhost) by alpo.whistle.com (8.8.5/8.8.5) id MAA18269; Thu, 18 Feb 1999 12:08:44 -0800 (PST) Received: from current1.whistle.com(207.76.205.22) via SMTP by alpo.whistle.com, id smtpdS18262; Thu Feb 18 20:08:36 1999 Date: Thu, 18 Feb 1999 12:08:25 -0800 (PST) From: Julian Elischer To: Robert Sexton Cc: freebsd@digistar.com, freebsd-hackers@FreeBSD.ORG Subject: Re: data buffers, disk i/o jsb In-Reply-To: <19990218111456.A2658@kudra.com> Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG On Thu, 18 Feb 1999, Robert Sexton wrote: > > Also, if I boot from the boot floppy for installtion and install the ports > > collection, the install moves at a much faster pace, like 15K/s. If I > > install the ports collection after the install is completed (booting from > > the hard disk) the install takes FOREVER, like 2K/s and there is a HUGE > > amount of disk access. The install mounts the disk in ASYNC mode. if you do ityourself you leave it in sync mode which os slow for file creation and directory operations (which is about ll there is in the ports tree). In 3.x you can run in "soft updates" mode and get much better performance. > > This really can't be helped. The ports filesystem on one of my > production machines contains almost 30k inodes. > Building it is a nightmare. I'm told it'll build quite quickly on an > asyncronous filesystem. (See Below) > > > Is there a compile-time option that I can compile into the kernel to > > improve disk caching/buffering? > > None that I'm aware of. However, there are a number of other, better options. > > a. Mount filesystems with the noatime flag. > This elimates a lot of inode updates when walking a large tree. > b. Mount filesystems async. This provides terrific performance > on large trees like ports, but is the digital equivalent of > no seatbelts in a convertable. > c. Switch to 3.0 and uses soft updates. This gives you most of the > performance of async, but with a high degree of safety. yep julian To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message