I ran the JavaWorld article's Tcl scripts and got similar (but slightly
slower) results
for the four tests (JDK 1.3.1, Jacl CVS 1.3).
Using a Profiler, I found a hot spot in Expression.java.
The code attempts to see if the parsed value is an integer (or double).
Unfortunately, it is passing non-numbers into strtod which is throwing
an expensive RuntimeException.
The attached fix was straightforward and borrows from the Tcl C code.
The performance improvement is significant:
Test 1 - For loop counting from 1 to 1,000,000
Before: 180 seconds
After: 50 seconds
Test 2 - Compare 1,000,000 integers for equality
Before: 368 seconds
After: 94 seconds
--
Shawn Boyce
QCOM, Inc.
Quality Software is Our Business
http://www.qcominc.com
|
