Firefly offers lots of options for MP2 energy and MP2 gradient
computations. Normally, defaults work just fine on almost every
system. Additional options can be used to fine tune Firefly and
to save some memory. There is no single universal set of best
options. You may need to perform some numerical experiments.
If you run Firefly on clusters with distributed network filesystem
like Lustre, gpfs, panfs etc... the most important parameters are
various record sizes. The default record sizes are good for local
disks but should be increased to 100000 or so for optimum
performance when running on non-local filesystems.
On Thu Jul 28 '16 12:34pm, GrEv wrote
>I found in the manual the following recommendations for MP2 geom. optimization for large systems:
>$MP2GRD DBLBF=.F. FUSED=.F. ASYNC=.T. $END
>I wonder why it is better to have DBLBF=.F. FUSED=.F., which are both .T. by default?