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A comment on JavaScript Array.push is 945x faster than Array.concat. Parent comment

Re:JavaScript Array.push is 945x faster than Array.concat by skohan on Thursday May 23, 2019 @11:39AM (#19992724)
Is this really done? It seems like this approach would require all arrays to be allocated with at least a page's worth of memory, which seems incredibly wasteful if you have a bunch of small arrays with a handful of floats or something.
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Re:JavaScript Array.push is 945x faster than Array.concat by Someone on Thursday May 23, 2019 @02:37PM (#19994553)
”It seems like this approach would require all arrays to be allocated with at least a page's worth of memory”

I don’t know whether it is done in practice, but you can postpone doing that until the array gets ‘big’, for some definition of ‘big’.

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Re:JavaScript Array.push is 945x faster than Array.concat by BubRoss on Thursday May 23, 2019 @02:59PM (#19994792)
Allocating a bunch of small arrays is going to be wasteful (performance wise) anyway. That being said, I'm not sure if this is done frequently or not.
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