From owner-freebsd-questions@FreeBSD.ORG Wed Dec 1 03:48:02 2004 Return-Path: Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id BA9A316A4CE for ; Wed, 1 Dec 2004 03:48:02 +0000 (GMT) Received: from obsecurity.dyndns.org (CPE0050040655c8-CM00111ae02aac.cpe.net.cable.rogers.com [69.194.102.143]) by mx1.FreeBSD.org (Postfix) with ESMTP id 87F5E43D41 for ; Wed, 1 Dec 2004 03:48:02 +0000 (GMT) (envelope-from kris@obsecurity.org) Received: by obsecurity.dyndns.org (Postfix, from userid 1000) id E52F3512B1; Tue, 30 Nov 2004 19:53:16 -0800 (PST) Date: Tue, 30 Nov 2004 19:53:16 -0800 From: Kris Kennaway To: r.p.demarco@att.net Message-ID: <20041201035316.GA20429@xor.obsecurity.org> References: <20041201032716.8FBA043D5C@mx1.FreeBSD.org> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-sha1; protocol="application/pgp-signature"; boundary="YZ5djTAD1cGYuMQK" Content-Disposition: inline In-Reply-To: <20041201032716.8FBA043D5C@mx1.FreeBSD.org> User-Agent: Mutt/1.4.2.1i cc: freebsd-questions@freebsd.org Subject: Re: Can 10M Buffer Ceiling be lowere? X-BeenThere: freebsd-questions@freebsd.org X-Mailman-Version: 2.1.1 Precedence: list List-Id: User questions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Wed, 01 Dec 2004 03:48:02 -0000 --YZ5djTAD1cGYuMQK Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Wed, Dec 01, 2004 at 03:27:11AM +0000, r.p.demarco@att.net wrote: > A technical question: >=20 > I have an old NEC computer (c. 1997) running 5.3-RELEASE with > 48M of RAM. Getting a new computer isn't an option right now, but > I would like to get as much out of my memory as possible. > My /boot/kernel/kernel file is about 3M, and from the initial > boot:=20 > real memory =3D 50331648 (48 MB) > avail memory =3D 43896832 (41 MB) > it appears this kernel takes up about 7M of memory with one screen saver > kld loaded. With a few unneeded services (cron, sendmail) disabled, I > start off with about 26M free after a fresh reboot with just root logged = in, > running `top'. Looking at top, I noticed: >=20 > Mem: 4320K Active, 15M Inact, 12M Wired, 10M Buf, 11M Free > ^^^ >=20 > From TOP(1): >=20 > Buf: number of pages used for BIO-level disk caching >=20 > Actually, the 10M is after some disk usage (it starts ~6M). > It never gets above 10M. Is there anyway to adjust this, to > (say) a maximum of 5M? Yes, a new 256 MB RAM system would be nice, > but until then, I would like to avoid serious paging running xclock :) > Thanks, There's no point, that memory will be used if demanded. Note that you still have 11M free in your example, so throwing away 6MB that is used for caching would only *reduce* performance. Kris --YZ5djTAD1cGYuMQK Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.2.6 (FreeBSD) iD8DBQFBrUAsWry0BWjoQKURAvDIAKCo3JETaDZgVQaZkTF+5kkoXZQ4ggCgyDFM bEkMBZiuvQuJ3H8062gRcBg= =NBok -----END PGP SIGNATURE----- --YZ5djTAD1cGYuMQK--