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Re: A question about synchronized threads

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From	Deeyana <d.awlberg@hotmail.invalid>
Newsgroups	comp.lang.java.programmer
Subject	Re: A question about synchronized threads
Date	Wed, 4 May 2011 00:17:06 +0000 (UTC)
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On Tue, 03 May 2011 18:57:19 -0400, Lew wrote:

> byhesed wrote:
>> I thought that synchronizing entire methods would be wasteful.
>
> Why?

It is well known that shorter critical sections and finer lock 
granularity can increase concurrency, Lew.

> Also, if two methods are "totally unrelated to each other" then you
> don't need any synchronization at all.

Classic unsubstantiated and erroneous claim. They may still need 
synchronization to prevent the simultaneous use of a) the SAME one by two 
different threads on the same object or b) one of them and some third 
method on the same object. But you may want an explicit lock object 
instead of the default effects of declaring the methods synchronized.

> The single best, most effective way to optimize concurrent code is not
> to share data.  The second-best way is to make shared-data immutable
> (read-only).

Clojure can help a lot with the latter.

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Thread

A question about synchronized threads byhesed <byhesed@gmail.com> - 2011-04-29 08:35 -0700
  Re: A question about synchronized threads Lew <noone@lewscanon.com> - 2011-04-29 11:53 -0400
    Re: A question about synchronized threads byhesed <byhesed@gmail.com> - 2011-04-29 09:12 -0700
      Re: A question about synchronized threads Eric Sosman <esosman@ieee-dot-org.invalid> - 2011-04-29 21:01 -0400
        Re: A question about synchronized threads byhesed <byhesed@gmail.com> - 2011-04-29 18:43 -0700
  Re: A question about synchronized threads Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-04-29 17:58 +0200
    Re: A question about synchronized threads byhesed <byhesed@gmail.com> - 2011-04-29 09:09 -0700
      Re: A question about synchronized threads markspace <-@.> - 2011-04-29 11:11 -0700
        Re: A question about synchronized threads Daniele Futtorovic <da.futt.news@laposte-dot-net.invalid> - 2011-04-29 20:19 +0200
          Re: A question about synchronized threads markspace <-@.> - 2011-04-29 15:21 -0700
          Re: A question about synchronized threads Patricia Shanahan <pats@acm.org> - 2011-04-29 21:10 -0700
  Re: A question about synchronized threads dagon@dagon.net (Dagon) - 2011-04-29 15:55 -0700
    Re: A question about synchronized threads Alice <quaxx1108@example.com> - 2011-04-29 20:08 -0400
    Re: A question about synchronized threads markspace <-@.> - 2011-04-29 19:07 -0700
    Re: A question about synchronized threads byhesed <byhesed@gmail.com> - 2011-04-29 18:49 -0700
      Re: A question about synchronized threads Lew <noone@lewscanon.com> - 2011-05-03 18:57 -0400
        Re: A question about synchronized threads Deeyana <d.awlberg@hotmail.invalid> - 2011-05-04 00:17 +0000
          Re: A question about synchronized threads Lew <noone@lewscanon.com> - 2011-05-04 12:45 -0400
            Re: A question about synchronized threads Deeyana <d.awlberg@hotmail.invalid> - 2011-05-04 19:59 +0000

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