jkelly061597
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sleep() versus wait(obj) performance
I have a multithreaded app where threads pause for a certain amounts of time. In some cases I also wake them up part way through the process.
Is using Object.wait() a more expensive operation than Thread.sleep() when using them for a threading pause? I.e. memory or processing costs... etc.
Is using Object.wait() a more expensive operation than Thread.sleep() when using them for a threading pause? I.e. memory or processing costs... etc.
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ASKER
I know the abilities of each. I am looking for performance information.
ASKER
Possible question: Are they implemented in the JVM in a way that makes one worse off than the other?
I suspect that both Wait and Sleep behave the same way about counting the time before they resume control of the Thread. However, since Java isn't meant to be a real-time langauge, I suppose there could be variances between different JVM implementations and also about how each method is naitivly implemented within the same JVM. Best bet about getting performance information is to conduct tests on your own with a program that performs calls on both Wait and Sleep and logs the data.
neithe sleep nor wait 'count time' they just hang themself up in a que designed for processes 'waiting for a time interrupt' after telling the system when they want the interrup.
wait has some slightly more complex admin-chores to do because it can also be reactivated by a notify.
The difference is miniscule though. If your appication is so timecritical that it matters you should probably be using C or C++ instead.
wait has some slightly more complex admin-chores to do because it can also be reactivated by a notify.
The difference is miniscule though. If your appication is so timecritical that it matters you should probably be using C or C++ instead.
>> If your appication is so timecritical that it matters you should probably be using C or C++ instead
Just what I was thinking ;-)
Also, if the general principle is that the pause should occur for a specific amount of time, you'll need extra code (eg. a Timer) in order to manage the wait/notify anyway.
Just what I was thinking ;-)
Also, if the general principle is that the pause should occur for a specific amount of time, you'll need extra code (eg. a Timer) in order to manage the wait/notify anyway.
ASKER
Thanks everyone,
Just FYI: This is not a time critical app, but a performance critical app so I'm just checking.
Just FYI: This is not a time critical app, but a performance critical app so I'm just checking.
wait allows you to pause, and get restarted when some other thread "notifies" that the situation may have changed. Depending on your situation, the latter may be more efficient.