Bug#973412: libdune-istl-dev: package should recommend libscotchparmetis-dev

[Markus Blatt]

Package: libdune-istl-dev
Version: 2.6.0-2
Severity: normal

Dear Maintainer,

I think that libdune-istl-dev should at least recommend libscotchparmetis-dev
(or better: even depend on it like for superlu and libsuitesparse). The
parallel version of the AMG will suffer from scalability issues otherwise. Note
that the non-free libparmetis-dev would resolve this, too, but is not usable by
everybody.

   * What led up to the situation?

Installing libdune-istl-dev without installing either libparmetis-dev or
libptscotchparmetis-dev.
Write an example program that uses AMG and run it on a parallel computer with
more than 32 processes.
>From a certain number of processes you will see a warning : "Successive
accumulation of data on coarse levels only works with ParMETIS installed."

   * What exactly did you do (or not do) that was effective (or
     ineffective)?

To remedy I need to install libscotchparmetis-dev and recompile the program.

   * What was the outcome of this action?

Having libscotchparmetis-dev makes the warning go away

   * What outcome did you expect instead?

I expected that just installing libdune-istl-dev would actually install
libscotchparmetis-dev to make using the more scalable version of the parallel
AMG solver the default in other/user DUNE modules.

Thanks a lot in advance!

Cheers,

Markus



-- System Information:
Debian Release: 10.6
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable-debug'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 4.19.0-12-amd64 (SMP w/32 CPU cores)
Kernel taint flags: TAINT_PROPRIETARY_MODULE, TAINT_OOT_MODULE, TAINT_UNSIGNED_MODULE
Locale: LANG=de_DE.UTF-8, LC_CTYPE=de_DE.UTF-8 (charmap=UTF-8), LANGUAGE=de_DE.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)
LSM: AppArmor: enabled

Versions of packages libdune-istl-dev depends on:
ii  libdune-common-dev  2.6.0-3
ii  libsuitesparse-dev  1:5.4.0+dfsg-1
ii  libsuperlu-dev      5.2.1+dfsg1-4

libdune-istl-dev recommends no packages.

Versions of packages libdune-istl-dev suggests:
pn  libdune-istl-doc  <none>

-- no debconf information