SPEC Benchmark Specifications - 094.fpppp
Fpppp is a double precision floating point FORTRAN benchmark. It is
difficult to vectorize because it contains very large basic
blocks.
Fpppp is a quantum chemistry benchmark which measures perfor-
mance on one style of computation (two electron integral
derivative) which occurs in the GaussianXX series of pro-
grams. It does very little I/O. The input to the program is
the number of atoms. The amount of computation to be done is
proportional to the fourth power of the number of atoms.
Fpppp has been run on machines ranging from PC's to supercom-
puters. A discussion of the algorithm implemented in fpppp
may be found in an article by H.B.Schlegel, Journal of Chemi-
cal Physics, volume 77, page 3676 (1982).
H.B. Schlegel, Wayne State University, Detroit, Michigan.
Elapsed time in seconds.
Elapsed time. On most systems, the sum of system+user time
should be very close to the elapsed time, as this benchmark
does little I/O. The SPEC reference time (to 3 sig. fig.) is
9200 seconds.
Emits a short table of floating point values and an integer
count of the number of calls to FMTGEN. The floating point
results should agree exactly except for a possible rounding
error in the last place. The number of calls to FMTGEN may
vary by 1 or 2 %.
FORTRAN
Many. See next section.
Fpppp has run on Unix machines, VMS machines, and others in-
cluding Macintosh and Cray XMP.
Difficult if not impossible to vectorize.
The executable should be well under 1MB. Optimized compila-
tion may require substantial swap space (because of the large
basic blocks).
time ./fpppp < ./input.ref/natoms
Floating point results should agree exactly except for a pos-
sible rounding error in the last place. The number of calls
to FMTGEN may vary by 1 or 2 %.