>Try (4) only for starters ( you may want to play with 64 and try different values) , and take it to 500 iterations so you can compare with the previous results
Same thing - start with ~0.14 sec. and end with 1.73 sec.
I'm thinking - can it help to sleep for, say, 2 sec. after 50 iterations?
If it's not broken, fix it until it is.
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