Does standby affect computing program execution?

Question

I have a Windows notebook on which I'm running some heavily computing program. Since I cannot easily stop that program, and since I needed to move my laptop and I couldn't keep it on for a long time, I put it into standby mode. When I turned it on again, I found my program apparently working exactly as if it never stopped. So I wonder: does standby mode suspend program execution and then start it back again EXACTLY as it was? Or could that affect program execution causing errors over computing results or something? Thank you very much

Matteo

Answer 1

When the OS enters standby mode, it suspends normal running programs and powers down unnecessarily system components. Everything is maintained in RAM, however, which is why the system continues to draw power. When the system wakes up, your program is un-suspended. Unless it listens for the relevant power events (or detects the large jump in time from the realtime clock), it doesn't even know it was suspended.

So for instance, if you had a program that was working its way through 10,000,000 records, and it was processing record 4,000,000 when it was suspended, it would continue processing that record when it was un-suspended (picking up exactly where it left off).

Answer 2

I'm not an expert on this but just wanted to add a thought- the state (and environment) of the computer may change when moving in and out of standby mode.

The most common example I can think of is moving between wireless networks while in standby mode. If your program uses network specific identifiers these will have changed and hence the program may not recover well.

Another example is big jumps in time if you are using the internal clock for say timestep calculations.

I guess the observed impact depends on the properties of the executing program itself.