Usually the SFX are in fact stored directly into RAM. Depending on RAM budgets and file size of SFX I've seen them streamed before, but it's not the best way to go typically...

If for sure a specific sound effect isn't going to be used then I'm sure you can dump it from the buffer if you're trying to squeeze in another sfx.

Do you have some RAM limitiations with something or what?

Tony

Disk I/O of any kind during a game level will typicall cause a glitch in the frame rate; it's a very noticeable jerk when that happens. Thus, most games pre-load everything they'll need for a level.

Some games, notably those with extremely large, "streaming" or "paging" worlds, will load and unload data as needed, and will use asynchronous I/O (on UNIX), overlapped I/O (on Windows), or a separate disk loading thread (any platform) to get rid of that glitch, because most of the glitch is just spent doing nothing while waiting for the call to read() to return (which in turn is waiting for hardware, so the CPU is idle).