From owner-freebsd-hackers Thu Mar 7 10:53:38 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from goose.prod.itd.earthlink.net (goose.mail.pas.earthlink.net [207.217.120.18]) by hub.freebsd.org (Postfix) with ESMTP id 4DE5837B400 for ; Thu, 7 Mar 2002 10:52:56 -0800 (PST) Received: from pool0314.cvx21-bradley.dialup.earthlink.net ([209.179.193.59] helo=mindspring.com) by goose.prod.itd.earthlink.net with esmtp (Exim 3.33 #1) id 16j30X-00027u-00; Thu, 07 Mar 2002 10:52:54 -0800 Message-ID: <3C87B6F6.C56CC50C@mindspring.com> Date: Thu, 07 Mar 2002 10:52:38 -0800 From: Terry Lambert X-Mailer: Mozilla 4.7 [en]C-CCK-MCD {Sony} (Win98; U) X-Accept-Language: en MIME-Version: 1.0 To: Zhihui Zhang Cc: freebsd-hackers@freebsd.org Subject: Re: A question of VM page ownership References: Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG Zhihui Zhang wrote: > Is there any fundamental reason why a page can not be owned by more than > one VM object? If that was the case, the bogus page stuff in vfs_bio.c > could be made cleaner IMHO. When you need to reclaim the page, you would have to identify all owners, rather than a single owner. THis converts the lookup fron an O(1) to an O(N) problem. Keeping a linked list of owners doesn't really help, either, since it introduces locking issues that will cause -current to blow chunks. -- Terry To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message