Retrieves statistics about the global memory utilization.
Returns FALSE on failure, or an array consisting of the following information on success:
The current memory load in percent of physical memory.
This is always 1024, and indicates that the following values are the count of 1024 bytes.
The amount of total physical memory.
The amount of still available physical memory.
The amount of total pageable memory (physical memory + paging file).
The amount of still available pageable memory (physical memory + paging file).
The amount of total virtual memory for a process.
The amount of still available virtual memory for a process.