Emscripten memory leak

Question

I have a javascript function compiled from C with Emscritpen which use some amount of memory (about 8mb), and I need to call it often. (One call per 20 sec).

But after every call the amount of used memory increases. And eventually it starts to fail with:

Cannot enlarge memory arrays. Either (1) compile with -s TOTAL_MEMORY=X with X higher than the current value 100663296, (2) compile with ALLOW_MEMORY_GROWTH which adjusts the size at runtime but prevents some optimizations, or (3) set Module.TOTAL_MEMORY before the program runs.

If I increase an amount of memory, it works longer, but still fails eventually. I don't understand why EMScripten tries to enlarge a HEAP size after each call.

Some code samples:

var render = Module.cwrap('render_djvu', 'number', ['string']);

call:

FS.createDataFile("/", "test.djvu", byteArray, true, true);
removeRunDependency();
var heapPointer = render('test.djvu');
FS.truncate('test.djvu', 0);
FS.unlink('test.djvu');

UP: The problem was a memory leak in C++ code, we didn't free an allocated by C code memory. Eventually we were running out of space for heap and it required an increase. The HEAP array is persistent and is not cleared after each invocation as I initially thought.

Answer 1

I solved the issue. I didn't understand that if you are allocating memory in C/C++ program which will be compiled in JS. I though that on every call EMScripten will generate the new clear environment, which is not the case and the environment will be reused. So we still care about memory leaks.