I was wondering if there are any slight difference between the definitions of :
As I understand that we are using multithreading to achieve multiprogramming . Should the parallel processing the same as multiprogramming ,or it's related to hardware ?
Thanks
Multiprogramming describes that you are able to run multiple programms on a computer at the same time (compared to an old eg DOS system where only one program at a time could run) (also sometimes refered as mutlitasking) -> multiprogramming
Multithreading has to be seen differently on description: -> multithreading
Hardware Multithreading or Architecture: a Processor is able to run multiple Threads in parallel (for real, counterexample: Multiprogramming)
Software Mutlithreading: is when one Process consists of multiple threads those threads are not independent to each other, like processes, especially those threads can have race conditions while working on the same data (-> difference between thread & process )
Parallel processing desribes that there are some ( > 1) CPU's working togehter in any kind. This includes one PC with a multi-core, one server with multiple processors (eg on cards) or even a network of computers -> Parallel processing
The way I've usually seen your 2nd and 3rd terms used:
Parallel processing refers to two or more threads running at the same time, each working with their own data. That is, beyond starting and stopping, there are few, if anym synchronization problems. Multithreading refers to much the same thing, except that the threads share data and must be very careful about this. That is, synchronization is everything.
Proper parallel processing is not much harder than running a single thread. (Most platforms provide all kinds of support to help keep it simple.) Multithreading is a lot of very hard work.
