What do the various Virtual Memory metrics indicate?
Ah, the ever-so-confusing virtual memory defintions. Even programmers are sometimes confused by them. Here I’ll try to clear them up. I haven’t much time, so its just a quick explanation. You will need to know the basics of virtual memory to understand it. Virtual memory is an abstraction layer, allowing what you (and processes) think of as ‘memory’ to be stored in any combination of phsyical media and shared between processes. It has numerous benefits. For one, it lets you have a very large amount of memory, since virtual memory is limited only by the space available on the page files’ storage medium (hard drives or SSDs). Secondly, it is easily shared since duplicated memory can simply ‘point’ to the first copy of it. There are many sother benefits as well. When virtual memory is accessed (a hard page fault), it is moved into RAM (page in or swapped in). When it is unused for a longe period, it is moved to the SWAP file (paged out). All this is transparent to the process. The process
