What is the difference between physical and virtual memory on a computer?

Question

I have used almost all of my physical memory, but I have alot of virtual memory. What is the virtual memory for?

Answer 1

Phishical Refers to anything pertaining to hardware. The opposite of physical is logical or virtual, which
describe software objects. For example, physical memory refers to the actual RAM chips installed in a
computer. Virtual memory, on the other hand, is an imaginary storage area used by programs.

Answer 2

Physical Memory : This is electronic memory of a computer. also a main memory.
Virtual Memory - This is system memory that is simulated by the hard drive. When all the RAM is being used (for example if there are many programs open at the same time) the computer will swap data to the hard drive and back to give the impression that there is slightly more memory. This is your hard disk memory. You can decide how much virtual memory you need in windows by setting the parameters in Performance option.

Answer 3

The computer hardware that is the primary memory system of a computer (normally RAM). The term is only used in contrast to logical memory or Virtual memory.

Virtual memory or virtual memory addressing is a memory management technique, used by computer operating systems, more common in multitasking OSes, wherein non-contiguous memory is presented to a software (aka process) as contiguous memory. This contiguous memory is referred to as the virtual address space.

Virtual memory addressing is typically used in paged memory systems. This in turn is often combined with memory swapping (also known as anonymous memory paging), whereby memory pages stored in primary storage are written to secondary storage (often to a swap file or swap partition), thus freeing faster primary storage for other processes to use.

In technical terms, virtual memory allows software to run in a memory address space whose size and addressing are not necessarily tied to the computer's physical memory. To properly implement virtual memory the CPU (or a device attached to it) must provide a way for the operating system to map virtual memory to physical memory and for it to detect when an address is required that does not currently relate to main memory so that the needed data can be swapped in. While it would certainly be possible to provide virtual memory without the CPU's assistance it would essentially require emulating a CPU that did provide the needed features.

Answer 4

32 bit machines can address 4GB's

64 bit machines can effectives address unlimited (about 16e18 bytes)

You don't have that much memory so when you run out of physical memory...The computer writes out some not heavily used bits of memory to disk and opens up that area for a needed present memory...Also known as paging out...And when it needs the info, it gets it from disk and puts some other bits of memory on disk if physical memory is still full.

Answer 5

physical--> RAM in the computer
vitual---> logical memory allocated on the hard drive

hope that helps =D