[jira] Updated: (DERBY-3731) Improve calculation of refSize in ClassSize.java

> Improve calculation of refSize in ClassSize.java
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>
>                 Key: DERBY-3731
>                 URL: https://issues.apache.org/jira/browse/DERBY-3731
>             Project: Derby
>          Issue Type: Bug
>          Components: SQL
>            Reporter: Kathey Marsden
>            Priority: Minor
>         Attachments: derby-3731-1a-refsize_from_properties.diff, DERBY-3731_diff.txt
>
>
> java/engine/org/apache/derby/iapi/services/cache/ClassSize.java has a static code block which calculates the size of a reference for the architecture.  This code could be improved by adding garbage collection before measuring memory, to give a consistent  reading.     Also there have been suggestions that we use os.arch or sun.arch.data.model to make the measurement more reliable, especially on 64bit machines.