lockfile doesn't work on some lustre systems

[jlinford]

[TAU] Unable to acquire lock on /lustre/scratch1/turquoise/sameer/taucmdr-120/system/.lock [TAU] due to [Errno 38] Function not implemented

[jlinford]

This may be related to a variety of 'NoneType' object has no attribute errors on knl01.

[zbeekman]

To be clear, the lockfile is for atomically updating the project file, correct?

This may be overkill, but this blog post has some interesting ideas: https://renatocunha.com/blog/2015/11/ctypes-mmap-rwlock/

It looks like you can use mmap to share state between processes, even if they aren't launched from the same python script using multiprocessing etc.

The post in question uses ctypes to wrap posix rwlocks. This could be overkill.

Additional potentially helpful info:

• https://blog.schmichael.com/2011/05/15/sharing-python-data-between-processes-using-mmap/
• https://stackoverflow.com/questions/1829116/how-to-share-variables-across-scripts-in-python