what exactly is the difference between the usr and the sys seconds in the Benchmark reported timings?

In this particular example, the thing that will account for most of the system time is the program requesting more virtual memory (mostly heap) from the OS.

This is why the single loop over a large array spend a substantially larger proportion of the total time in systime relative to the large number of iterations over a small array.

In the former, the large amount of memory is allocated once and used once.

In the latter, the smaller amount of memory is allocated once for the first run and then reused many times.

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re: for v. map v. pdl by BrowserUk
in thread for v. map v. pdl by punkish

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