Benchmark isn't useful here. We don't have two snippets here. Benchmark finds the average of mulitple runs of different code. We want the times of two runs of the same code.

The problem at hand is not a comparison of perfomance of two snippets. The problem at hand is a slowdown (presumably related to virtual-memory) on the second run, even though the second run should be reusing the memory of the first run.

In reply to Re^2: Use of undef slowing down perl? by ikegami
in thread Use of undef slowing down perl? by thalej

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