Gentoo Archives: gentoo-portage-dev

From: "Michał Górny" <mgorny@g.o>
To: gentoo-portage-dev@l.g.o
Cc: Zac Medico <zmedico@g.o>
Subject: Re: [gentoo-portage-dev] [PATCH] Enable FEATURES=parallel-install by default (bug 715110)
Date: Tue, 12 May 2020 10:39:34
Message-Id: 09cf04ac74982e40ce62c87af31c24eff7052b57.camel@gentoo.org
In Reply to: Re: [gentoo-portage-dev] [PATCH] Enable FEATURES=parallel-install by default (bug 715110) by Zac Medico
1 W dniu wto, 12.05.2020 o godzinie 01∶40 -0700, użytkownik Zac Medico
2 napisał:
3 > On 5/11/20 10:54 PM, Michał Górny wrote:
4 > > W dniu nie, 10.05.2020 o godzinie 21∶32 -0700, użytkownik Zac
5 > > Medico
6 > > napisał:
7 > > > The feature enables finer grained locks for install operations,
8 > > > and
9 > > > everyone agrees that it's safe to enable by default.
10 > >
11 > > Who's 'everyone' and where's their analysis of the problem?
12 > > The manpage doesn't really help understand what this does, exactly.
13 >
14 > Before parallel-install there was just one big lock, so only one
15 > package
16 > slot could enter the merge/unmerge state at a given time.
17 >
18 > With parallel install, there are a few finer-grained locks that come
19 > into play. [...]
20
21 I'm sorry but I was asking of a more high-level implications.
22
23 I presume that this means that more than files of more than one package
24 can be merged simultaneously. However:
25
26 1. Are collisions handled correctly then? i.e. if you start installing
27 A, and then B, and the two packages collide will portage fail before
28 starting to install any file from B?
29
30 2. Are preinst/postinst phases called simultaneously or serialized?
31
32 --
33 Best regards,
34 Michał Górny

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