[Interest] Scalability of QTimer or QObject::startTimer

[Bo Thorsen]

Den 26-10-2012 11:18, Prashant skrev:
>
> Hi.
> I intend to have quite a few QObject inherited classes each 
> implementing a couple of timers. The resolution of these timers is 
> expected to be around 1000ms. However, QTimer documentation states that
> "If Qt is unable to deliver the requested number of timer clicks, it 
> will silently discard some."
> I don't know how to interpret this statement. Does it mean that if a 
> timer has a very low resolution, some clicks are neglected. OR does it 
> mean that if a significant number of clicks from various timers 
> happens at around the same time, clicks will be discarded.
> In my application, it is not so important to have the click delivered 
> at the exact same time, it doesn't matter if clicks are off by x ms. 
> However, if no clicks are delivered there is a problem. I intend to 
> have around 2000 objects. However, I intend to scale it to around 
> 100,000 QTimers.

It means if the thread is busy for so long that the timer should have 
fired X times, it may fire anything from 1 to X times. But it will at 
least fire once.

One note: If you have that many timers, Qt will have to do some tricks 
for you. It would normally use hardware timers, but I don't know of any 
system that offer 100.000 timers.

You might be better off implementing some sort of distribution object if 
that's possible.

Bo Thorsen.

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