[metis-users] New --time-limit command line argument

[Joe Hurd]

Responding to a feature request made by Andrés Sicard-Ramírez, I have
implemented a --time-limit N command line argument, which will cause
Metis to give up if it cannot complete within N seconds. Metis will
return "SZS status Unknown" it if is working on a problem and the time
limit kicks in.

The feature is implemented in Metis 2.3 (release 20100928), which can
be downloaded from

http://www.gilith.com/software/metis/

There are some caveats to this feature:

1. The timer is checked every time a clause is removed from the
waiting set and added to the active set. This is an expensive
operation, so Metis might continue to run past the time limit.

2. Metis has many failure modes beyond running out of time, such as
eating up all the memory it can find, so in most circumstances it is
preferable to use the ulimit shell command to set limits rather than
this command line argument.

Cheers,

Joe