My machine has 8GB of RAM and is running Windows Server 2008. malloc()/realloc() fails to allocate more memory when my application has 1.5~1.7GB already allocated. I tried switching to HeapAlloc()/HeapRealloc() instead and the same situation happens.
Is there something I am missing here? What could be causing my application to be unable to allocate more memory when there is clearly available RAM?
What could be causing my application to be unable to allocate more memory when there is clearly available RAM?
Heap fragmentation. Allocation doesn't simply ask for memory. It asks for a contiguous piece of memory.
Of course, given the sparse data you provided (how much are you trying to re-alloc when that happens? is this a 32bit or a 64bit app?), there could be other problems as well.