Buffers don't free up memory / OS doesn't return freed up memory

[Br3ikros]

Version

16.13.1

Platform

Windows, repl, heroku

Subsystem

No response

What steps will reproduce the bug?

simply run this:

function getPrintFile() {

    let buffer = Buffer.alloc(1000000);

    return

}

function test() {

    for (let i = 0; i < 10; i++) {
        console.log(process.memoryUsage())
        getPrintFile()
    }


}

test()
console.log(process.memoryUsage())

How often does it reproduce? Is there a required condition?

every time

What is the expected behavior?

the external and rss memory not building up and actually releasing memory. this is a big issue when using a lot of buffers for example for image manipulation

What do you see instead?

external and rss memory building up and not freeing

Additional information

It doesn't even work if you assign to the buffer a null value after declaring it

[bnoordhuis]

I've converted this to a discussion because it's pretty much expected behavior, not a bug. Variations of what you see have been reported many times before, the keywords you're looking for are 'memory fragmentation' and 'garbage collector'.

[Br3ikros]

hi. ok. but the garbage collector doesn't work when using it. i installed jemalloc on my server, same thing. how is it not a bug or an issue if every single buffer doesn't free up the memory used?