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From Alexey Solofnenko <A.Solofne...@mdl.com>
Subject Re: Tomcat with 8 GB memory
Date Sat, 28 Jul 2007 04:45:55 GMT
No, each of two 4GB processes will have only a half of the objects under 
the same load. And I heard that GC does not scale linear with heap size. 
And this is without multi-threading performance considerations.  As 
usual, your mileage may vary and only tests can tell for sure.

- Alexey.

Caldarale, Charles R wrote:
>> From: Alexey Solofnenko [mailto:A.Solofnenko@mdl.com] 
>> Subject: Re: Tomcat with 8 GB memory
>>
>> I was under impression that GC does not scale linearly. That 
>> means one 8GB process will be slower than two 4GB processes.
>>     
>
> Not true.  The time of a full GC using modern algorithms depends mostly
> on the number and type of live objects, not the amount of heap space.
> The number and type of live (reachable) objects stays relatively
> constant for most application once the ramp-up period is over.
> Consequently, running a single JVM with the largest heap you can fit in
> the process space is the most efficient from a GC point of view.  (Of
> course, there are plenty of other reasons not to put all your eggs in
> one basket.)
>
>  - Chuck
>
>
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-- 
------------------------------------------------------------------------
Alexey N. Solofnenko <http://trelony.cjb.net/>
Pleasant Hill, CA (GMT-8 usually)

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