From owner-freebsd-hackers@FreeBSD.ORG Thu Mar 12 18:55:57 2015 Return-Path: Delivered-To: freebsd-hackers@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115]) (using TLSv1.2 with cipher AECDH-AES256-SHA (256/256 bits)) (No client certificate requested) by hub.freebsd.org (Postfix) with ESMTPS id BDF4F502 for ; Thu, 12 Mar 2015 18:55:57 +0000 (UTC) Received: from mail.westryn.net (mail.westryn.net [199.48.135.251]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 86D3C94E for ; Thu, 12 Mar 2015 18:55:56 +0000 (UTC) Received: from ice.westryn.net (225x169.ouraynet.com [204.16.225.169]) (using TLSv1 with cipher ECDHE-RSA-AES256-SHA (256/256 bits)) (No client certificate requested) by mail.westryn.net (Postfix) with ESMTPSA id 890B994323E; Thu, 12 Mar 2015 12:55:54 -0600 (MDT) Content-Type: text/plain; charset=utf-8 Mime-Version: 1.0 (Mac OS X Mail 8.2 \(2070.6\)) Subject: Re: file system change notifications From: Kim Shrier In-Reply-To: <85EE0305-5D79-4C66-A6F4-05219655DAD5@mail.turbofuzz.com> Date: Thu, 12 Mar 2015 12:55:52 -0600 Content-Transfer-Encoding: quoted-printable Message-Id: References: <237A50A5-FAB7-4FC1-B8F1-0E40DCBF6137@dons.net.au> <5786089D-414D-485C-B675-35B5A62C5950@gmail.com> <85EE0305-5D79-4C66-A6F4-05219655DAD5@mail.turbofuzz.com> To: Jordan Hubbard X-Mailer: Apple Mail (2.2070.6) Cc: FreeBSD Hackers , "O'Connor, Daniel" , Guy Helmer X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.18-1 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Thu, 12 Mar 2015 18:55:57 -0000 On Mar 12, 2015, at 10:24 AM, Jordan Hubbard = wrote: >=20 >=20 >> On Mar 12, 2015, at 6:37 AM, Guy Helmer wrote: >>=20 >> How are Darwin (OS X) fsevents implemented? It=E2=80=99s a been a = handy interface for some of my work. >=20 > They have their own tap from the kernel and their own daemon = (fseventsd) to handle coalescing and a publish/subscribe model that will = feed multiple consumers without duplicating or losing events (I = haven=E2=80=99t looked deeply into the implementation, but presumably = all the cache management is there as well so that memory consumption can = be kept manageable. >=20 > Maybe someone should keep a list of =E2=80=9COS X features we would = really like in FreeBSD=E2=80=9D (add purgeable memory and memory = pressure bands to that list while you=E2=80=99re at it) and parcel them = out as GSoC projects. :-) >=20 > - Jordan I was curious if the OS X code, which I believe adds some functionality = to VFS along with fseventd for actually handling the notifications, = would be a good model for FreeBSD. I need to study the OS X code some = more to make sure I understand it. Also, to clarify, I am not proposing this as a GSoC project. I was just = referring to a GSoC project that seemed to address this problem. If I = can figure out a good approach for adding this to FreeBSD, I would do it = myself. Kim