Gentoo Archives: gentoo-user

From: Alan McKinnon <alan.mckinnon@×××××.com>
To: gentoo-user@l.g.o
Subject: Re: [gentoo-user] Re: Emerge order not deterministic !?
Date: Thu, 12 Nov 2015 08:31:16
Message-Id: 56444E0A.5030309@gmail.com
In Reply to: [gentoo-user] Re: Emerge order not deterministic !? by "Jörg Schaible"
1 On 12/11/2015 10:29, Jörg Schaible wrote:
2 > Alan McKinnon wrote:
3 >
4 >> On 11/11/2015 21:35, Walter Dnes wrote:
5 >>> Ongoing installation. I looked at 2 instances of
6 >>> "emerge -pv x11-base/xorg-server" and the order was somewhat different.
7 >>> Here are a couple of outputs, just a few seconds apart. Is this a bug
8 >>> or a feature? See attachments.
9 >>>
10 >>
11 >>
12 >> Emerge order is not deterministic, especially with parallel builds. The
13 >> reason is that it does not need to be according to the dep graph - if
14 >> two packages are at the same level and do not depend on each other, then
15 >> the order they are built in does not affect the final result.
16 >> Practically all parallel processing works this way.
17 >>
18 >> What is deterministic, is that if you build the same set of packages
19 >> twice and even if portage does them in different order, the binaries
20 >> produced are functionally identical
21 >
22 > Hmmm. And how can you then ever use
23 >
24 > emerge --resume --skip-fist
25 >
26 > if not even the first build is deterministic? I skip the first package
27 > anyway only if the problematic package is the first one to build after
28 > resume, but if I cannot even rely on that?
29
30
31 Because it re-uses the previous build order, not re-generate a new one.
32
33
34 --
35 Alan McKinnon
36 alan.mckinnon@×××××.com

Replies

Subject Author
[gentoo-user] Re: Re: Emerge order not deterministic !? "Jörg Schaible" <joerg.schaible@×××××××××.com>