(gcc returns mem) Re: When is it time for a 1.0 feature freeze?

[Walter Bright]

Bruno Medeiros wrote:
> Hum, I modified the program and tried 4 more tests:
> 
> Allocating 10000 (sequential) chunks of size 10000 bytes. Free them all.
> -> All the 100Mb of memory is returned to the OS.
> 
> Allocating 100000 (sequential) chunks of size 1000 bytes. Free them all.
> -> All the 100Mb of memory is returned to the OS.
> 
> Allocating 10000 (sequential) chunks of size 10000 bytes. Free only half 
> of them, the even numbered ones, so that the total freed memory is not 
> contiguous.
> -> Of the 50Mb memory free'd, about 30Mb of memory is returned to the 
> OS. Expected due to page segmentantion/rounding.
> 
> Allocating 100000 (sequential) chunks of size 1000 bytes. Again free 
> only the even numbered ones.
> -> 50Mb memory is free'd, but no memory is returned to the OS. Expected 
> due to page segmentantion/rounding.
> 
> So it seems glibc does its best, it returns any page if it is all free. 

So it does seem to, and so my statement is obsolete.