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vishaljain02_104484 asked Erick Ramirez edited

How does a memtable go off-heap?

How a memtable goesout of jvm heap memory?

memtables
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Erick Ramirez answered Erick Ramirez edited

[EDITED] Memtables are data structures stored on the JVM heap.

If you configure set memtable_allocation_type: offheap_objects, the memtable pool will be allocated from the available off-heap space. Otherwise, it will be allocated from the available heap. Cheers!

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vishaljain02_104484 avatar image vishaljain02_104484 commented ·

My initial understanding was Memtables will reside on JVM heap only but cassandra.yaml has memtable_heap_space_in_mb and memtable_offheap_space_in_mb properties because of which I got confused.

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Erick Ramirez avatar image Erick Ramirez ♦♦ vishaljain02_104484 commented ·

You should have asked that question instead. Let me update my response. Cheers!

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