Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 2 Apr 2014 12:48:08 -0400
From:      Glen Barber <gjb@FreeBSD.org>
To:        Brooks Davis <brooks@freebsd.org>
Cc:        svn-src-head@freebsd.org, svn-src-all@freebsd.org, src-committers@freebsd.org, Nikolai Lifanov <lifanov@mail.lifanov.com>
Subject:   Re: svn commit: r264027 - in head: release share/man/man7
Message-ID:  <20140402164808.GJ14379@glenbarber.us>
In-Reply-To: <20140402164128.GB70867@lor.one-eyed-alien.net>
References:  <201404012241.s31MfRW6020684@svn.freebsd.org> <20140402154022.GA70867@lor.one-eyed-alien.net> <20140402155134.GG14379@glenbarber.us> <533C32F5.9050809@mail.lifanov.com> <20140402160650.GH14379@glenbarber.us> <533C3992.9030203@mail.lifanov.com> <20140402163350.GI14379@glenbarber.us> <20140402164128.GB70867@lor.one-eyed-alien.net>

next in thread | previous in thread | raw e-mail | index | archive | help

--tKy6e3LXpfmanBFM
Content-Type: text/plain; charset=us-ascii
Content-Disposition: inline
Content-Transfer-Encoding: quoted-printable

On Wed, Apr 02, 2014 at 11:41:29AM -0500, Brooks Davis wrote:
> On Wed, Apr 02, 2014 at 12:33:50PM -0400, Glen Barber wrote:
> > On Wed, Apr 02, 2014 at 12:23:46PM -0400, Nikolai Lifanov wrote:
> > > On 04/02/14 12:06, Glen Barber wrote:
> > > > On Wed, Apr 02, 2014 at 11:55:33AM -0400, Nikolai Lifanov wrote:
> > > >> On 04/02/14 11:51, Glen Barber wrote:
> > > >>> On Wed, Apr 02, 2014 at 10:40:22AM -0500, Brooks Davis wrote:
> > > >>>> On Tue, Apr 01, 2014 at 10:41:27PM +0000, Glen Barber wrote:
> > > >>>>> Author: gjb
> > > >>>>> Date: Tue Apr  1 22:41:26 2014
> > > >>>>> New Revision: 264027
> > > >>>>> URL: http://svnweb.freebsd.org/changeset/base/264027
> > > >>>>>
> > > >>>>> Log:
> > > >>>>>   Add a new release build variable, WITH_COMPRESSED_IMAGES.
> > > >>>>>  =20
> > > >>>>>   When set to a non-empty value, the installation medium is
> > > >>>>>   compressed with gzip(1) as part of the 'install' target in
> > > >>>>>   the release/ directory.
> > > >>>>>  =20
> > > >>>>>   With gzip(1) compression, downloadable image are reduced in
> > > >>>>>   size quite significantly.  Build test against head@263927
> > > >>>>>   shows the following:
> > > >>>>>  =20
> > > >>>>>    bootonly.iso:		64% smaller
> > > >>>>>    disc1.iso:		44% smaller
> > > >>>>>    memstick.img:		47% smaller
> > > >>>>>    mini-memstick.img:	65% smaller
> > > >>>>>    dvd1.iso:		untested
> > > >>>>>  =20
> > > >>>>>   This option is off by default, I would eventually like to
> > > >>>>>   turn it on by default, and remove the '-k' flag to gzip(1)
> > > >>>>>   so only compressed images are published on FTP.
> > > >>>>
> > > >>>> I'd recommend testing xz compression as well.  With UFS images o=
f a full
> > > >>>> world the savings vs gzip are significant (more than 30% IIRC, b=
ut it's
> > > >>>> need more than a year since I checked so I'm a bit unsure of the=
 exact
> > > >>>> numbers).
> > > >>>>
> > > >>>
> > > >>> delphij also brought this up.
> > > >>>
> > > >>> I have concerns with xz(1), since there was mention in IRC that W=
indows
> > > >>> users may have problems decompressing xz-compressed images.  So, =
gzip(1)
> > > >>> is used because it seems to be the more commonly-supported archive
> > > >>> mechanisms.
> > > >>>
> > > >>> The benefit of xz(1) over gzip(1) was only 50M-ish.
> > > >>>
> > > >>>   -rw-r--r--  1 root  wheel   601M Mar 28 20:18 disc1.iso
> > > >>>   -rw-r--r--  1 root  wheel   381M Mar 28 20:18 disc1.iso.bz2
> > > >>>   -rw-r--r--  1 root  wheel   392M Mar 28 20:18 disc1.iso.gz
> > > >>>   -rw-r--r--  1 root  wheel   348M Mar 28 20:18 disc1.iso.xz
> > > >>>
> > > >>> Glen
> > > >>>
> > > >>
> > > >> How about 7zip (Windows program, not file format)? What would a Wi=
ndows
> > > >> user use that can decompress gzip and not xz? It was a problem aro=
und
> > > >> ~2007, but xz support is no longer rare or exotic.
> > > >>
> > > >=20
> > > > I don't know, to be honest.  I have no Windows machines to test, so
> > > > I can only go by what I am told.
> > > >=20
> > > > Glen
> > > >=20
> > >=20
> > > I just verified it with 7zip for Windows version 9.22. It extracts
> > > .tar.xz archives and decompresses .xz images.
> > >=20
> >=20
> > Great, thank you for confirming.
> >=20
> > So, the question I have now is, considering the time it takes to
> > compress the image with xz(1) compared to gzip(1), is that worth saving
> > the 50MB space?
> >=20
> > I do not object to using xz(1), but the compression time difference was
> > quite significant.  (I do not have numbers off-hand, but can run the
> > compression again.)
>=20
> xz is quite slow, but who cares if it's something we do once for the
> benefit of many.  One thing I did do in my build system is use pxz from
> ports.  It speeds things up quite a bit on many-core machines with lots
> of ram.
>=20

Based on the feedback received on this, I think it's clear that xz(1)
is the better choice, so I'll make the relevant changes shortly.

I was more worried about Windows users needing to go through pain to
decompress the images, which seems like a non-issue now.

Thanks Brooks and Nikolai for the input.

Glen


--tKy6e3LXpfmanBFM
Content-Type: application/pgp-signature

-----BEGIN PGP SIGNATURE-----
Version: GnuPG v2.0.22 (FreeBSD)
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=sPvA
-----END PGP SIGNATURE-----

--tKy6e3LXpfmanBFM--



Want to link to this message? Use this URL: <https://mail-archive.FreeBSD.org/cgi/mid.cgi?20140402164808.GJ14379>