From owner-freebsd-hackers Mon Nov 23 17:47:31 1998 Return-Path: Received: (from majordom@localhost) by hub.freebsd.org (8.8.8/8.8.8) id RAA17244 for freebsd-hackers-outgoing; Mon, 23 Nov 1998 17:47:31 -0800 (PST) (envelope-from owner-freebsd-hackers@FreeBSD.ORG) Received: from apollo.backplane.com (apollo.backplane.com [209.157.86.2]) by hub.freebsd.org (8.8.8/8.8.8) with ESMTP id RAA17239 for ; Mon, 23 Nov 1998 17:47:30 -0800 (PST) (envelope-from dillon@apollo.backplane.com) Received: (from dillon@localhost) by apollo.backplane.com (8.9.1/8.9.1) id RAA11543; Mon, 23 Nov 1998 17:47:24 -0800 (PST) (envelope-from dillon) Date: Mon, 23 Nov 1998 17:47:24 -0800 (PST) From: Matthew Dillon Message-Id: <199811240147.RAA11543@apollo.backplane.com> To: Terry Lambert Cc: joelh@gnu.org (Joel Ray Holveck), tlambert@primenet.com, DBECK@ludens.elte.hu, freebsd-hackers@FreeBSD.ORG Subject: Re: SYSV Semaphores & mmap problems References: <199811231937.MAA25048@usr02.primenet.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG The difference between mmap() and SysV shared memory isn't so bad. The mmap()'d file will basically get synced every 30 seconds or so by the syncer daemon. madvise() can be used to pre-fault any pages already in the cache. I think all that is needed is a way to flag a file so the syncer doesn't touch it under normal circumstances, instead allowing its pages to be synced by normal paging activity. You can then madvise(... MADV_FREE) the pages after you are through with the shared memory segment to throw them away. -Matt Matthew Dillon Engineering, HiWay Technologies, Inc. & BEST Internet Communications & God knows what else. (Please include original email in any response) To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message