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Threads in Java

Kontham Satish

Joined: Jun 19, 2006
Posts: 1
How many thread types are in java?(i know only one daemon thread)
Nishant Verma
Ranch Hand

Joined: Jun 14, 2006
Posts: 41
These are some of the JVM thread types, I know :

1. Daemon threads - used in the background to implement a service. To create daemon thread thread.setDaemon(true). JVM exits when the only running threads are daemon.

2. Green threads - are pseudo threads. These are user level threads. Sun wrote green threds to enable thread support where native threds cannot be used. But I am not sure, if that means that green threads **CANNOT** be time sliced or round robin'ed. However this should depend strictly on the scheduler.

3. Native threads - To create native thread you need to run native VM use "-native" option. These threads can definitely be scheduled by OS scheduler.

I am not sure if Sun's Hot Spot VM still uses green threads on Solaris. But if they do then I think it shouldnt run faster than native implementation.


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subject: Threads in Java
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