Completely agree with you here. This is an edge case. Indeed the job of the script is to extract a subset of the columns from the original data set and reduce amount of data.

Presently the desire to preserve original ordering together with some infrastructural limitations hinder migration to Hadoop-like platforms.

Nonetheless the present version in use already is quite fast in comparison to the version used before (could speed up the python version I got as a legacy to about using about 1/2 of original time and at same time still improve stability.) Ideas of migration to other languages (as Perl, ...) were born out of academic interest (after seeing the improvements possible just in the legacy code) but didn't result in much progress yet. (Finally another step forward came with a multithreaded tcl implementation.)

During the process I at least learned to admire the guys who created the string splitting and joining routines in the various scripting languages. These are enlightening examples of highly optimized code.

P.S.: perl version is embarrassingly short, use of global variables is definitly no issue; I only was amazed to see that the use of lexical variables resulted in a performance penalty.

In reply to Re^2: "my" slowing down programs? by jf1
in thread "my" slowing down programs? by jf1

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