From owner-freebsd-hackers@freebsd.org Sun Dec 6 03:17:23 2015 Return-Path: Delivered-To: freebsd-hackers@mailman.ysv.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:1900:2254:206a::19:1]) by mailman.ysv.freebsd.org (Postfix) with ESMTP id 7C601A3B0B2 for ; Sun, 6 Dec 2015 03:17:23 +0000 (UTC) (envelope-from lists@eitanadler.com) Received: from mail-wm0-x22d.google.com (mail-wm0-x22d.google.com [IPv6:2a00:1450:400c:c09::22d]) (using TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)) (Client CN "smtp.gmail.com", Issuer "Google Internet Authority G2" (verified OK)) by mx1.freebsd.org (Postfix) with ESMTPS id 2B60A1A30 for ; Sun, 6 Dec 2015 03:17:23 +0000 (UTC) (envelope-from lists@eitanadler.com) Received: by wmvv187 with SMTP id v187so123330662wmv.1 for ; Sat, 05 Dec 2015 19:17:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=eitanadler.com; s=0xdeadbeef; h=mime-version:in-reply-to:references:from:date:message-id:subject:to :content-type; bh=jClvSs7UwWJAglVnTVshmTBnbtHD+pdplgIXVB/CP4o=; b=pf93EdzVbsegCId7UrzFZu4sG1poxhCAi0C9hZLnZZNbISGnqVMbClGCWjmwgZD/Wi jF0EkKDgkjK6sOgqJawbczn/mZbiMcWXvmybUL0CrkhtahlR4L+WG0rIxwXT5SzoS0xl OJXnRxRdERoNjm9dUr95jpmsrRM1GLvlPdswE= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20130820; h=x-gm-message-state:mime-version:in-reply-to:references:from:date :message-id:subject:to:content-type; bh=jClvSs7UwWJAglVnTVshmTBnbtHD+pdplgIXVB/CP4o=; b=ir8hnEh7HjJTVIwIHSw/iPcs5wwrly3El1qsm0MnBgIpvtq/igNe/9KU3n+/41ixrA 3gmOk2MEo8TK5ZcTgnVhBBuOdfULu8m6F5OMWEtIciWFRrjinbAKl8knGCCEcBRf2Aff A7yVOGXYhor/143QgWHL/uXkvdDVRrabXlYYnp9JJvaK6QjiQcQrJSTzriMUcSDjcacK 7MsolBour0IpZBwkLc8vpeM699xH6uMRRQ7dULySN2lCOiMc/2NYYapZ57qFvSBjY5CS CuGq11OWZDJeALYSyjNzUTKMVz/3+MDkcfRqZsb8mx4YYZMEKx8Vlm73piAja8T3WdgL rXeQ== X-Gm-Message-State: ALoCoQkIbn8zy02olA8MXzkEmr1Mm3uwV+UT2wb7md19nvbLL6nWvHvVRq4e4MH6fZVIZ3fegBDl X-Received: by 10.28.128.210 with SMTP id b201mr12724149wmd.69.1449371841085; Sat, 05 Dec 2015 19:17:21 -0800 (PST) MIME-Version: 1.0 Received: by 10.28.43.1 with HTTP; Sat, 5 Dec 2015 19:16:51 -0800 (PST) In-Reply-To: References: From: Eitan Adler Date: Sat, 5 Dec 2015 19:16:51 -0800 Message-ID: Subject: Re: DELETE support in the VOP_STRATEGY(9)? To: Maxim Sobolev , FreeBSD Hackers , Pawel Jakub Dawidek Content-Type: text/plain; charset=UTF-8 X-BeenThere: freebsd-hackers@freebsd.org X-Mailman-Version: 2.1.20 Precedence: list List-Id: Technical Discussions relating to FreeBSD List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 Dec 2015 03:17:23 -0000 + correct mailing list - non-technical list On 4 December 2015 at 21:38, Maxim Sobolev wrote: > Hi folks, do we support delete operation in the vnode layer? This comes from > observation that md(4) converts from DELETE into sector-size zero buffer > write before it feeds it to the vnode. It's shame that a trim operation is > getting lost when you run md(4)+ufs atop a vnode. With the magnetic spinning > storage joining home particle accelerators, aka CRTs in the hall of fame > soon, we better make sure it's turtles all the way down in either direction. > By which I mean make sure that trim can not only propagate from VFS to BIO > but also the other way around . I believe having this would also allow > "punch-hole" API in the userland to be implemented trivially, syscall that > VM's out there would love to have. > > -Max -- Eitan Adler