sbrk(2) broken

Peter Schuller peter.schuller at
Wed Jan 9 10:22:46 PST 2008

> Actually, malloc(3) can use madvise(2) to notify the kernel that
> arbitrary pages in the arena are unused and can be discarded.  The
> current implementation will do so if the H option is specified.

Ah, interesting. I was not aware of that.

However, in this context it will likely only help partially since you still 
need a full page to be free (and with a lot of programs many allocations will 
be significantly smaller than that, and I have to assume no real-life malloc 
will align all allocations to pages, or the overhead would be extreme).

/ Peter Schuller

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