From owner-freebsd-hackers Tue Jun 18 7:50:36 2002 Delivered-To: freebsd-hackers@freebsd.org Received: from gate.nentec.de (gate2.nentec.de [194.25.215.66]) by hub.freebsd.org (Postfix) with ESMTP id AB12F37B407 for ; Tue, 18 Jun 2002 07:50:23 -0700 (PDT) Received: from nenny.nentec.de (root@nenny.nentec.de [153.92.64.1]) by gate.nentec.de (8.11.3/8.9.3) with ESMTP id g5IEoGA27241; Tue, 18 Jun 2002 16:50:16 +0200 Received: from nentec.de (andromeda.nentec.de [153.92.64.34]) by nenny.nentec.de (8.11.3/8.11.3/SuSE Linux 8.11.1-0.5) with ESMTP id g5IEoAZ22415; Tue, 18 Jun 2002 16:50:10 +0200 Message-ID: <3D0F48A2.9080902@nentec.de> Date: Tue, 18 Jun 2002 16:50:10 +0200 From: Andy Sporner User-Agent: Mozilla/5.0 (X11; U; Linux i686; de-AT; rv:0.9.8) Gecko/20020204 X-Accept-Language: de-at, de, en, en-us MIME-Version: 1.0 To: joy ganguly Cc: freebsd-hackers@FreeBSD.ORG Subject: Re: mmap and MAP_NOSYNC References: <20020618143756.42830.qmail@web8007.mail.in.yahoo.com> Content-Type: text/plain; charset=us-ascii; format=flowed Content-Transfer-Encoding: 7bit X-Virus-Scanned: by AMaViS-perl11-milter (http://amavis.org/) 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 joy ganguly wrote: >Hi all, > >Hi, > >I want to use mmap as a means of doing IPC between >unrelated processes. I do *not* want the data to hit >the disk. So this is what I do :- > >fd = open(file, O_RDWR); >p = mmap(fd, MAP_NOSYNC | MAP_SHARED); >mlock(p, len); > >/* Whack around with shmem */ > > >Now my question is , once I have wired the shared >memory region, is it possible that the data still hits >the disk ? One would think the pager will not look at >wired pages. Is that correct ? > Is there some reason not to use SYSV shared memory??? Andy To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message