sleep function duration changes when system clock is modified

rubyonrails-talk
1

My problem is related to the behaviour of sleep function. If, during the execution of sleep function, I change the system clock of my PC, sleep function will not recover from sleeping when it should.

Example:

My controller:

def index   logger.info "Start sleeping at:"+Time.now.to_s   sleep 5   logger.info "Sleeping finished at:"+Time.now.to_s end

Everythink works well if I don't change the system time during the execution of sleep function. However, if during the execution of sleep function I shift the system time, let's say 1 minute back, I'll need to wait 1 minute and 5 seconds until the sleep function finishes.

I'd need to force sleep function to sleep always 5 seconds, even if the system time changes during the call of the sleep function.

If I try somethink similar in pure ruby (no rails), everythink works as expected, I can change system time without any consequences to the behaviour of sleep function.

I am using Rails 1.2.1 under WinXP.

Thanks for your help.

2

The server application will be running on customer's PC and the sleep function is used in a background thread. In these conditions, the manual change of system clock may happen and I would'nt like if this freezed the background thread.