Okay. Since you are not getting much help so far, here is a second half-brained idea: maybe what you are seeing is related to the deallocation of the @orders array created during the previous run. You could test that theory by keeping those around and see if your timings change at all.

In reply to Re^3: Performance oddity when splitting a huge file into an AoA by roubi
in thread Performance oddity when splitting a huge file into an AoA by Xenofur

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