From owner-freebsd-hackers Wed Feb 28 13:37:38 2001 Delivered-To: freebsd-hackers@freebsd.org Received: from earth.backplane.com (earth-nat-cw.backplane.com [208.161.114.67]) by hub.freebsd.org (Postfix) with ESMTP id BC54837B719 for ; Wed, 28 Feb 2001 13:37:36 -0800 (PST) (envelope-from dillon@earth.backplane.com) Received: (from dillon@localhost) by earth.backplane.com (8.11.2/8.9.3) id f1SLbMs91698; Wed, 28 Feb 2001 13:37:22 -0800 (PST) (envelope-from dillon) Date: Wed, 28 Feb 2001 13:37:22 -0800 (PST) From: Matt Dillon Message-Id: <200102282137.f1SLbMs91698@earth.backplane.com> To: Peter Dufault Cc: Anton Berezin , hackers@FreeBSD.ORG Subject: Re: how to actually find out whether data hit the disk? References: <200102281357.f1SDvVW27830@hda.hda.com> Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG :> is it possible to actually find out whether data hit the disk or not for :> a particular run of 1-7? : :Answer to your question: : :Do an msync with MS_SYNC someplace. Also, use MAP_NOSYNC in :mmap until 4.3 when Matt Dillon plans to make that the default behavior. I plan on making it the default behavior only for Linux emulation, to emulate what Linux does. For FreeBSD native you still need to specify MAP_NOSYNC. Eventually I hope to make it the default behavior for FreeBSD native but some work needs to be done on the VM heuristics first (or on an incremental system sync) to avoid collecting too many dirty pages. -Matt To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message