[Pkg-db-devel] Bug#520926: Bug#520926: Bug#520926: should be built with --enable-posixmutexes --with-mutex=POSIX/pthreads

[Clint Adams]

On Wed, Apr 22, 2009 at 09:13:50PM -0400, John Morrissey wrote:
> Hm, I'm really not sure I'm the one to answer that question (if it's indeed
> me you're asking it of). I've already backported and forked libdb4.7
> locally, so I filed this bug mostly as an FYI that this is a change you
> might want to make to the Debian packaging, since it seems to result in more
> optimal outcomes on NPTL systems.

Just to catch you up on history:

During our transition to NPTL, it was possible for Berkeley DB to be built
on a system with NPTL support and then be installed on a system without
working NPTL, where libdb would be completely unable to function.

We solved this problem by forcing BDB to build with assembly mutexes
(which were rife with portability problems on some of the less popular
architectures).

When it once again became safe to use NPTL-built packages, we returned
to the vendor defaults.  In the case of amd64, the default is 
POSIX/pthreads/library/x86_64/gcc-assembly, and as I recall, this is
the only architecture for which people complain about performance.