interfaces/blas/C/testing/sanity.out|\\

fgrep-v PASSED

make[1]:[sanity_test]Error1(ignored)

DONE

SCOPING FOR FAILURES IN F77BLAS TESTS:

fgrep-e fault-e FAULT-e error-e ERROR-e fail-e FAIL\\

interfaces/blas/F77/testing/sanity.out|\\

fgrep-v PASSED

make[1]:[sanity_test]Error1(ignored)

DONE

make[1]:Leaving directory‘/home/whaley/TEST/ATLAS3.7.36.0/obj64’Notice that the Error1(ignored)commands come from make,and they indicate that fgrep is not?nding any errors in the output?les(thus this make output does not represent the?nding of an error).When true errors occur,the lines of the form

8cases:8passed,0skipped,0failed

will have non-zero numbers for failed,or you will see other tester output discussing errors,such as the printing of large residuals.

As mentioned,this is really sanity checking,and it runs only a few tests on a handful of problem sizes.This is usually adequate to catch most blatant problems(eg.,compiler producing incorrect output).More subtle or rarely-occurring bugs may require running the LAPACK and/or full ATLAS testers.The ATLAS developer guide[24]provides instructions on how to use the full ATLAS tester,as well as help in diagnosing problems.The developer guide is provided in the ATLAS tar?le as ATLAS/doc/atlas devel.pdf

6The ATLAS time step

In this optional step,ATLAS times certain kernel routines and reports their performance as a percentage of clock rate.Its purpose is to provide a quick way to ensure that your install has resulted in a library that obtains adequate performance.If you are installing using architectural defaults,this step will print a timing comparison against the performance that the ATLAS maintainer got when creating the architectural defaults.To invoke this step,issue the following command in your BLDdir:

make time

In Figure2we see a typical printout of a successful install,in this case ran on my2.4Ghz Core2Duo.The Refrenc columns provide the performance achieved by the architectural defaults when they were originally created,while the Present columns provide the results obtained using the new ATLAS install we have just completed.We see that the Present columns wins occasionally(eg.single precision real kSelMM),and loses sometimes(eg.single precision complex kSelMM),but that the timings are relatively similar across the board.This tells us that the install is OK from a performance angle.

As a general rule,performance for both data types of a particular precision should be roughly comparable,but may vary dramatically between precisions(due mainly to di?ering vector lengths in SIMD instructions).