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question

dmngaya avatar image
dmngaya asked ·

Why is a 32 GB heap allocation not recommended?

What can happend if someone use 32GB not 31 GB?

cassandratuning
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1 Answer

Erick Ramirez avatar image
Erick Ramirez answered ·

@dmngaya 32GB of heap can fit less objects in it than a 31GB heap due to the way the Java VM object addresses get allocated in a 64-bit system. It's a quirk of Java's memory management.

If you're interested, this blogpost on blog.codecentric.de has sample code and a more detailed explanation of why you can't use the extra space in heap sizes between 31GB and ~45GB. Cheers!

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