HINT(1)

NAME
hint - scalable benchmark for CPU and memory

SYNOPSIS
hint

DESCRIPTION
The program hint reveals many aspects of computer performance: operation speed, precision, memory bandwidth, and usable memory size. HINT measures "QUIPS" (QUality Improvement Per Second) as a function of time. "Net QUIPS" is a single number that summarizes the QUIPS over time.

As provided, hint tests double-precision floating point arithmetic. The original source can be re-compiled to test other data types (such as long integers). The original source should be available directly from ftp://ftp.scl.ameslab.gov/pub/HINT/. See http://www.scl.ameslab.gov/Projects/HINT/ for more information on HINT, including technical reports and an on-line database of HINT results.

The output of hint is a file in the directory data named DOUBLE which contains five columns:

1.  Time

2.  QUIPS

3.  Quality

4.  Subintervals

5.  Memory Used

The first two columns are used to produce the QUIPS graph. The third and fourth columns are Quality and subintervals. These columns can be used to check for loss of quality due to insufficient precision and poor choices of which rectangle to split. The fifth is useful for finding the sizes of memory regimes, like where primary cache saturates or where virtual memory is first invoked.

The file is set up in a format suitable for gnuplot(1) or similar plotting packages. QUIPS graphs should be plotted on a semi-log scale with log of time as the horizontal axis and QUIPS as the vertical axis. The following gnuplot commands would be suitable to display the QUIPS graph from the file data/DOUBLE:
set logscale x
plot "data/DOUBLE"
QUIPS vs. memory use can also be plotted to reveal memory regime sizes, by using the following gnuplot(1) command:
plot "data/DOUBLE" using 5:2

FILES
DOUBLE output file in the directory
    data

SEE ALSO
gnuplot(1)

AUTHOR
HINT was developed by the Scalable Computing Laboratory (SCL) of Ames Laboratory, a US Department of Energy laboratory.

BUGS
hint only writes its output file in the directory data.