From owner-freebsd-pkg@FreeBSD.ORG  Thu May 15 16:38:59 2014
Return-Path: <owner-freebsd-pkg@FreeBSD.ORG>
Delivered-To: freebsd-pkg@freebsd.org
Received: from mx1.freebsd.org (mx1.freebsd.org [8.8.178.115])
 (using TLSv1 with cipher ADH-AES256-SHA (256/256 bits))
 (No client certificate requested)
 by hub.freebsd.org (Postfix) with ESMTPS id BEB717D6
 for <freebsd-pkg@freebsd.org>; Thu, 15 May 2014 16:38:59 +0000 (UTC)
Received: from kithrup.com (Kithrup.COM [64.142.31.202])
 (using TLSv1 with cipher DHE-RSA-AES256-SHA (256/256 bits))
 (Client did not present a certificate)
 by mx1.freebsd.org (Postfix) with ESMTPS id 8BFF729C9
 for <freebsd-pkg@freebsd.org>; Thu, 15 May 2014 16:38:59 +0000 (UTC)
Received: from kithrup.com (localhost [127.0.0.1])
 by kithrup.com (8.14.4/8.14.4) with ESMTP id s4FGcpUx075878
 for <freebsd-pkg@freebsd.org>; Thu, 15 May 2014 09:38:51 -0700 (PDT)
 (envelope-from sef@kithrup.com)
Received: (from sef@localhost)
 by kithrup.com (8.14.4/8.14.4/Submit) id s4FGcpk8075877;
 Thu, 15 May 2014 09:38:51 -0700 (PDT) (envelope-from sef)
Date: Thu, 15 May 2014 09:38:51 -0700 (PDT)
From: Sean Eric Fagan <sef@Kithrup.COM>
Message-Id: <201405151638.s4FGcpk8075877@kithrup.com>
To: freebsd-pkg@freebsd.org
Subject: Re: Delta packages
X-BeenThere: freebsd-pkg@freebsd.org
X-Mailman-Version: 2.1.18
Precedence: list
List-Id: Binary package management and package tools discussion
 <freebsd-pkg.freebsd.org>
List-Unsubscribe: <https://lists.freebsd.org/mailman/options/freebsd-pkg>,
 <mailto:freebsd-pkg-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-pkg/>
List-Post: <mailto:freebsd-pkg@freebsd.org>
List-Help: <mailto:freebsd-pkg-request@freebsd.org?subject=help>
List-Subscribe: <https://lists.freebsd.org/mailman/listinfo/freebsd-pkg>,
 <mailto:freebsd-pkg-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Thu, 15 May 2014 16:38:59 -0000

>It is my understanding that pkgng keeps the old packages in
>/var/cache/pkg. Wouldn't it be easier to implement delta packages as
>binpatches between the decompressed tar streams of the two package versions?

That is a cache only, and cannot be counted upon.  And in our environment, we
are not going to keep the package file around after it's been installed.