Array append performance

[Walter Bright]

Lionello Lunesu wrote:
> The problem is that the timing for the small arrays cannot be trusted as 
> there's more overhead than actual code being tested. I've changed your 
> code by doing each test 100_000_000/i times. I've also added 'cpuid' for 
> synchronization, as Don suggested:

I suspect that copying the same data over and over again is not 
representative of actual usage, and so is not giving useful results.

I also do not understand the usage of cpuid here. I've used rdtsc for 
years for profiling purposes, and it has given me results that match the 
clock-on-the-wall results.