On 2 Aug 2013, at 13:21, David Matthews <David.Matthews at prolingua.co.uk> wrote:
?. Please try out the SVN version and let me know how it goes. ?
I am grateful to Phil Clayton for pointing out a surprising performance issue that he noticed while building ProofPower. He found that the elapsed time for the build was over 3 minutes with the latest development version and less than 1.5 minutes with version 5.5, even though the user and system times were about the same. I repeated the experiments and got similar results.
The problem is easy to reproduce. E.g., construct a source file perftest.ML containing the following:
structure PerfTest = struct fun f x = x; end;
Then run
time echo 'use"perftest.ML"' | poly
WIth 5.5, I get:
real 0m0.016s user 0m0.003s sys 0m0.010s
With the latest version (SVN rev 1838), I get:
real 0m0.416s user 0m0.003s sys 0m0.010s
The ProofPower build runs Poly/ML about 180 times. The results I am seeing are compatible with an overhead of about 400ms on each of these runs.
Regards,
Rob.