[Pvfs2-developers] disabling NPTL

[Phil Carns]

The configure script for pvfs2 has an option called 
"--enable-nptl-workaround" that will replace the pvfs2-server executable 
with a shell script that sets an environment variable before launching 
the real executable.  The environment variable causes PVFS2 to run 
against the old style pthread implementation that does not use NPTL.

This is the environment variable that the script currently uses:

LD_ASSUME_KERNEL=2.2.5

However, on newer distributions that doens't work.  You have to use this 
value instead:

LD_ASSUME_KERNEL=2.4.1

I don't know if there is any good way to tell which you are supposed to 
use in general, or if there is one good value that works everywhere.

It probably isn't a big deal anymore, since all of the NPTL 
implementations that ship with major distributions are stable now.  It 
is a handy option to be able to have for debugging thread problems, though.

-Phil