I had the thought that the extreme bais for the first run I demonstrated above (with large numbers of smallish allocations going on), might be due to the first run having 'virgin' heap to allocate from?

On second and subsequent runs, the heap has a long chain of free blocks that have to be traversed and/or coallesed when allocating the memory.

That seems to be born out by the fact that the bias reduces markedly with each extra iteration the first test completes.

Am I venting hot air again?

Examine what is said, not who speaks.
"Efficiency is intelligent laziness." -David Dunham
"Think for yourself!" - Abigail
"Memory, processor, disk in that order on the hardware side. Algorithm, algoritm, algorithm on the code side." - tachyon

In reply to Re^2: Benchmark.pm: Does subroutine testing order bias results? (twice is nice) by BrowserUk
in thread Benchmark.pm: Does subroutine testing order bias results? by jkeenan1

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