From owner-freebsd-questions Mon Jan 22 2:52:59 2001 Delivered-To: freebsd-questions@freebsd.org Received: from citusc17.usc.edu (citusc17.usc.edu [128.125.38.177]) by hub.freebsd.org (Postfix) with ESMTP id 222C837B400 for ; Mon, 22 Jan 2001 02:52:41 -0800 (PST) Received: (from kris@localhost) by citusc17.usc.edu (8.11.1/8.11.1) id f0MAtfT84157; Mon, 22 Jan 2001 02:55:41 -0800 (PST) (envelope-from kris) Date: Mon, 22 Jan 2001 02:55:41 -0800 From: Kris Kennaway To: cjclark@alum.mit.edu Cc: questions@FreeBSD.org Subject: Re: small program eats lot of memory Message-ID: <20010122025541.B84078@citusc17.usc.edu> References: <14955.1209.195848.394006@guru.mired.org> <01012121054701.03293@buffy> <20010121152246.X10761@rfx-216-196-73-168.users.reflex> <20010121165041.A76170@citusc17.usc.edu> <20010121203207.F10761@rfx-216-196-73-168.users.reflex> Mime-Version: 1.0 Content-Type: multipart/signed; micalg=pgp-md5; protocol="application/pgp-signature"; boundary="/WwmFnJnmDyWGHa4" Content-Disposition: inline User-Agent: Mutt/1.2.5i In-Reply-To: <20010121203207.F10761@rfx-216-196-73-168.users.reflex>; from cjclark@reflexnet.net on Sun, Jan 21, 2001 at 08:32:07PM -0800 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG --/WwmFnJnmDyWGHa4 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline Content-Transfer-Encoding: quoted-printable On Sun, Jan 21, 2001 at 08:32:07PM -0800, Crist J. Clark wrote: > > No, I believe he is correct. If you have two shared programs in > > memory, the VM system will only have one copy of the libc code shared > > between them (similarly with any other common libraries). >=20 > That's really something if it's true. I don't see any mention of > features like that on rtld(1). It's a generic feature of the VM system which shared libraries happen to incidentally benefit from. If you map the same object more than once, it only maintains one copy of it in VM, until one of the users dirties a page (changes something), at which point the page is copied ("copy on write"). Kris --=20 NOTE: To fetch an updated copy of my GPG key which has not expired, finger kris@FreeBSD.org --/WwmFnJnmDyWGHa4 Content-Type: application/pgp-signature Content-Disposition: inline -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.0.4 (FreeBSD) Comment: For info see http://www.gnupg.org iD8DBQE6bBGsWry0BWjoQKURAvWnAKDzBOgXq9r6aWTHxkXfnCVcx9IIgACeN8eL j3xBsYoKmjyHxiYYsJzvJ98= =sxQi -----END PGP SIGNATURE----- --/WwmFnJnmDyWGHa4-- To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message