Bug#989550: suitesparse: enhance 64-bit support in suitesparse

[M. Zhou]

Hi Drew,

Thanks for the proposal. Just for your information,
there is a WIP branch on suitesparse64:
https://salsa.debian.org/science-team/suitesparse/-/commits/lumin

I just ... ummm ... need some time to finish it.
Of course, any help would be appreciated.


On Mon, 2021-06-07 at 12:56 +0200, Drew Parsons wrote:
> Package: suitesparse
> Severity: normal
> Control: block -1 by 961183
> Control: block 961977 by -1
> 
> We've been introducing a 64 bit-build for the computational stack.
> This refers mainly to 64-bit indexing, enabling computation of
> extremely large systems (billions of degrees of freedom)
> 
> Some packages are already 64-bit enabled, including BLAS, PETSc.
> 
> SuiteSparse handles the 64-bit question by defining SuiteSparse_long
> (and using idx_t with metis). If I understand the SuiteSparse
> configuration correctly, this means a specific configuration option
> doesn't need to be set for SuiteSparse to compute large systems.
> 
> But as part of the 64-bit computation stack in Debian, we'd need to
> provide a separate suitesparse64 build in order to link suitesparse
> against blas64 or metis64. (I'm assuming this is a thing we would
> want
> to do in the context of 64-bit computation).
> 
> This affects cholmod, for instance, in the sense that cholmod uses
> idx_t defined in metis.h.  IDXTYPEWIDTH is the quantity in metis.h
> which we'll need to set to 64, in order to provide 64-bit Metis (this
> is requested in Bug#961183).
> 
> Once metis64 is available, we'll be free to provide suitesparse64
> i.e. libsuitesparse64-dev (it might be that header files can be
> transferred to a libsuitesparse-common-dev to share with
> libsuitesparse-dev),
> libcholmod64-3 (or similar), etc.
> 
> Once suitesparse64 is available, we'll be able link it from petsc64,
> which is currently linking to the standard build of suitesparse.
> 
> Drew
> 
> 
> -- System Information:
> Debian Release: 11.0
>   APT prefers testing-security
>   APT policy: (500, 'testing-security'), (500, 'unstable'), (1,
> 'experimental')
> Architecture: amd64 (x86_64)
> Foreign Architectures: i386
> 
> Kernel: Linux 5.10.0-7-amd64 (SMP w/8 CPU threads)
> Kernel taint flags: TAINT_OOT_MODULE
> Locale: LANG=en_AU.UTF-8, LC_CTYPE=en_AU.UTF-8 (charmap=UTF-8),
> LANGUAGE=en_AU:en
> Shell: /bin/sh linked to /usr/bin/dash
> Init: systemd (via /run/systemd/system)
> LSM: AppArmor: enabled
>