Quick question: I see the following formula used for determining the initial JVM Max Heap Size documented in the VE InfoCenter and Redbooks.
+Initial heap calculation = 90MB + 0.05 MB/req * peak req./sec * Desired time between garbage collections (GC)+
This is compared to the suggested calculation from the IMPACT 2012 VE Best Practices presentation:
+JVM heap size (in MB) = 90 + MR (max requests per second ODR is to handle)+
Is the best practice from the IMPACT 2012 session the new accepted practice?
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 20120530T17:20:30Z by SystemAdmin
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Pinned topic ODR Initial JVM Heap Size setting
20120529T15:30:17Z

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Updated on 20120530T17:20:30Z at 20120530T17:20:30Z by SystemAdmin

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Re: ODR Initial JVM Heap Size setting
20120530T12:25:41Z in response to SystemAdminIt turns out that the 2nd formula is a simplification of the 1st formula.
You can try both and you will come out with the same or very close to the same answer.
Keith
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Re: ODR Initial JVM Heap Size setting
20120530T12:28:00Z in response to KeithSTo clarify a bit ...
The 2nd formula is a simplification of the 1st formula in which we determine the recommended time between GCs for you.
Keith
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Re: ODR Initial JVM Heap Size setting
20120530T14:13:02Z in response to KeithSKeith,
Thanks for clarifying. Two follow up questions then:
 This calculation is for max heap size, correct?
 For the new calculation, if I expected my ODRs to handle 1000 requests per second then my initial max heap size would be 1090MB, correct?

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Re: ODR Initial JVM Heap Size setting
20120530T15:39:50Z in response to SystemAdminYes, and yes.
Keith
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Re: ODR Initial JVM Heap Size setting
20120530T17:20:30Z in response to KeithSAwesome! Thanks!!


