From owner-freebsd-hackers@FreeBSD.ORG  Sun Aug 11 06:47:12 2013
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
Delivered-To: freebsd-hackers@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 ESMTP id 84F5E6F9
 for <freebsd-hackers@freebsd.org>; Sun, 11 Aug 2013 06:47:12 +0000 (UTC)
 (envelope-from yuri@rawbw.com)
Received: from shell0.rawbw.com (shell0.rawbw.com [198.144.192.45])
 by mx1.freebsd.org (Postfix) with ESMTP id 6F6B225E3
 for <freebsd-hackers@freebsd.org>; Sun, 11 Aug 2013 06:47:12 +0000 (UTC)
Received: from eagle.yuri.org (stunnel@localhost [127.0.0.1])
 (authenticated bits=0)
 by shell0.rawbw.com (8.14.4/8.14.4) with ESMTP id r7B6lBOf011438;
 Sat, 10 Aug 2013 23:47:11 -0700 (PDT) (envelope-from yuri@rawbw.com)
Message-ID: <5207336F.5070307@rawbw.com>
Date: Sat, 10 Aug 2013 23:47:11 -0700
From: Yuri <yuri@rawbw.com>
User-Agent: Mozilla/5.0 (X11; FreeBSD amd64;
 rv:17.0) Gecko/20130628 Thunderbird/17.0.7
MIME-Version: 1.0
To: Patrick Dung <patrick_dkt@yahoo.com.hk>
Subject: Re: Discussing ideas or wish list
References: <mailman.7.1376049601.82585.freebsd-hackers@freebsd.org>
 <1376066075.81690.YahooMailNeo@web193503.mail.sg3.yahoo.com>
In-Reply-To: <1376066075.81690.YahooMailNeo@web193503.mail.sg3.yahoo.com>
Content-Type: text/plain; charset=ISO-8859-1; format=flowed
Content-Transfer-Encoding: 7bit
Cc: "freebsd-hackers@freebsd.org" <freebsd-hackers@freebsd.org>
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.14
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
 <freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/options/freebsd-hackers>, 
 <mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
 <mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 11 Aug 2013 06:47:12 -0000

On 08/09/2013 09:34, Patrick Dung wrote:
> Some (crazy?) ideas:
> a) Is it possible to install multiple Perl versions in the same server?
> Each third party Perl packages would linked to the corresponding Perl versions?
> Users have to update /usr/bin/perl to link to the desired Perl version (or using wrapper mechanism like /etc/mail/mail.conf).

Being able to create multiple unique environments on the same host is 
very beneficial.

I believe Oracle Solaris on ZFS is able to install individual packages 
into separate zones, and ZFS can share certain zones between each other.
Manipulating sharing rules allows creation of exactly this: various 
unique set of packages in top-level zones. So for example, perl and all 
its dependent packages can be installed multiple times in multiple 
versions in different ZFS zones on top of shared dependency packages.

Unfortunately, FreeBSD version of ZFS lacks zones.

Yuri