Re: [OE-core] Add package managers as a plugin

["Fredrik Gustafsson" <fredrik.gustafsson@axis.com>]

Hi Ross,
those 5 seconds will increase to minutes for my use case and we build a lot
hence I hope this will save us a lot of computer power and engineering time.
For example I've sent numbers on building a bigger image (core-image-sato-sdk-ptest)
to Alex and Alex:
out.apk.1: 1:13.35
out.apk.2: 1:13.51
out.apk.3: 1:13.23
out.apk.4: 1:14.07
out.apk.5: 1:13.00
out.deb.1: 3:49.37
out.deb.2: 3:50.77
out.deb.3: 3:51.39
out.deb.4: 3:53.40
out.deb.5: 3:53.99
out.ipk.1: 2:38.99
out.ipk.2: 2:39.07
out.ipk.3: 2:35.34
out.ipk.4: 2:36.15
out.ipk.5: 2:34.55
out.rpm.1: 1:58.61
out.rpm.2: 1:59.42
out.rpm.3: 1:59.70
out.rpm.4: 1:58.96
out.rpm.5: 1:58.11

Also consider that if we've a target without python with limited space, rpm is out
of the question. So the real comparison would be between ipk and apk. Let's
say we can save 80 seconds in each build. Now multiply that with the number of
builds, and we do a lot (I guess we might approach 100 000 builds/week in the
next year). Then this will save 92.5 days build time each week.

That's why I'm passionated about this.

/Fredrik
________________________________________
From: Ross Burton <ross@burtonini.com>
Sent: Friday, June 26, 2020 12:52 PM
To: Fredrik Gustafsson
Cc: OE-core; tools-cfpbuild-internal; Hugo Cedervall
Subject: Re: [OE-core] Add package managers as a plugin

On Thu, 25 Jun 2020 at 11:14, Fredrik Gustafsson
<fredrik.gustafsson@axis.com> wrote:
> Poky today has three different package managers, the well-known formats deb
> and rpm is supported as well as ipkg that is good for embedded devices.
>
> When building and having a good cache hit, a significant amount of time is
> spent in the phase of generating a rootfs, which is really about the
> performance of the package manager. ipkg is way slower than deb or rpm. To
> save build time and also get a package manager that is suitanle for use on
> targets where flash memory is a concern, support for apk is suggested.
>
> However, it might or might not be what's wanted for Poky since it increases
> the test matrix. Therefore this patch series refactors the package
> management code so that it's possible to add more package managers in other
> own layer. I will send another patch serie that will add apk.

As to the code review I mostly second what Paul said.

However, obviously you actually have strong feelings on this as the
series represents a fair amount of work.  What are the compelling
reasons to use apk?  Five seconds on core-image-minimal doesn't really
sell it to me, I don't think anyone ever claimed that opkg has been
performance optimised, dpkg isn't really used that much: maybe we
should re-evaluate what package managers are supported if apk has
feature parity but is significantly faster or has other advantages.

Ross