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Re: java thread question

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Roedy Green於 2014年4月4日星期五UTC+8上午8時52分54秒寫道：
> On Thu, 3 Apr 2014 07:51:16 -0700 (PDT), mcheung63@gmail.com wrote,
> 
> quoted or indirectly quoted someone who said :
> 
> 
> 
> >    I have write a little program to keep running some threads, i got questions:
> 
> >1) All threads are running within one process (ps command show me this), but it will eat up all cpu cores, how to explain this?
> 
> >2) If thread will eat multiple cpu core, why wee need fork/join in java?
> 
> 
> 
> what do you mean by "eat"?
> 
> 
> 
> Threads join the queue of processes to execute. the OS schedules them
> 
> on the next available CPU core.  So if you have 7 threads and 4 cores,
> 
> you can have 4 of those threads running at once.
> 
> 
> 
> Your threads compute just like independent jobs, though the OS can do
> 
> proprietary clever things.
> 
> 
> 
> When you exec/fork, you spin off a separate job than runs
> 
> independently in a separate address space.   The spawner can fail and
> 
> the child keeps going.  The child can be written in a different
> 
> language. The child have very limited ability to communicate with the
> 
> spawner.  A thread has access to the shared address space directly.
> 
> 
> 
> -- 
> 
> Roedy Green Canadian Mind Products http://mindprod.com
> 
> "The question of whether machines can think is about as relevant 
> 
> as the question of whether submarines can swim"
> 
> ~ Edsger Wybe Dijkstra (born: 1930-05-11 died: 2002-08-06 at age: 72)

thanks Roedy

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java thread question mcheung63@gmail.com - 2014-04-03 07:51 -0700
  Re: java thread question Nigel Wade <nmw@ion.le.ac.uk> - 2014-04-03 16:17 +0100
  Re: java thread question Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-04-03 11:43 -0400
    Re: java thread question mcheung63@gmail.com - 2014-04-03 15:10 -0700
      Re: java thread question Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-04-03 19:00 -0400
        Re: java thread question mcheung63@gmail.com - 2014-04-04 09:29 -0700
  Re: java thread question Roedy Green <see_website@mindprod.com.invalid> - 2014-04-03 17:52 -0700
    Re: java thread question mcheung63@gmail.com - 2014-04-04 09:31 -0700
    Re: java thread question Roedy Green <see_website@mindprod.com.invalid> - 2014-04-04 09:49 -0700
      Re: java thread question mcheung63@gmail.com - 2014-04-05 09:41 -0700

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