Eli Zaretskii <eliz@gnu.org> writes:

>> From: Ihor Radchenko <yantar92@gmail.com>
>> Date: Sat, 23 Nov 2019 22:37:44 +0800
>> 
>> If I open a large (>250) photos using the code below, the memory usage
>> increases permanently even after I close all the image buffers and wait
>> for some time. 
>
> For some background on this, see
>
>   https://unix.stackexchange.com/questions/53447/does-free-unmap-the-memory-of-a-process
>   https://stackoverflow.com/questions/1421491/does-calling-free-or-delete-ever-release-memory-back-to-the-system
>
> I think what you see is just normal behavior of memory allocation in
> glibc.