Subject: Re: [vserver] Debian Support
From: Christoph Lukas <christoph.lukas@gmx.net>
Date: Tue, 29 Sep 2009 16:28:43 +0200

Hi Mark,

> I've only recently started using Linux-VServer but I am really impressed
> by its performance so far.  I was initially having problems with the Lenny
> kernel's but then discovered Ben's beautiful repository and have had some
> servers running stable for weeks now.
> 
> Anyway, I was wondering how much work is actually involved in maintaining
> a kernel image?  With Debian's slow release cycle it seems that once they
> stick with a kernel for a release, you only get updated kernel's when the
> whole release gets updated or there are major security fixes required.  

Yes, once you have setup a kernel for one Debian release you just have
to keep up with the security updates and apply those to your kernel.

> So
> I figured generally there is going to be a /trunk kernel image updated and
> then you just need to apply the current VS patch against it and package it?

Hm. As the Debian / Ubuntu kernel teams applies quite some additional
patches to the vanilla kernel, applying a Linux-VServer patch against a
Debian kernel tree might not be that easy. 

I have build vserver kernels for the last 4 or 5 Ubuntu releases and
using an original Linux-VServer patch as a base I always got 5 to 15
rejects which I had to fix manually.
This sometimes is very easy. But sometimes it requires some real work
(at least for me). :)

> I am definitely overdue for giving back to FOSS so this is something I may
> be able to commit some time to.. however I want to make sure I am not
> getting in over my head here and end up letting the project down.
> 
> Can anyone estimate how much time they think it would take per week/month,
> etc?  and if it would generally be in waves of some busy weeks then quiet
> for a month or two, or pretty steady?

I would estimate I have spent about 5 days in setting up a working build
environment, scripts, package archive...

For every Debian release I would estimate another 1-2 days for the
initial Linux-VServer kernel. This includes: choosing a vserver patch,
adapting it till it applies cleanly, build and test the kernel.

For every security update I would estimate about 2 hours for building,
testing and uploading the kernel image.

I have found the Ubuntu Launchpad build service [1] extremely useful. I
would strongly suggest using something similar for Debian kernel images.

If you are interested in the work I did for the Ubuntu kernels please
take a look at [2] and [3].

Cheers,
Christoph

[1]: https://launchpad.net/ubuntu/+ppas
[2]: https://launchpad.net/~christoph-lukas/+archive/ppa
[3]: http://git.pingworks.net/