get_range_slice leads to java.lang.OutOfMemoryError?

[Gautam Singaraju]

I call the get_range_slice method in Java to get the list of all keys
in Cassandra db. The db is pretty small, about 1.3GB on disk. I
received the following error on the server:

"java.lang.OutOfMemoryError: Requested array size exceeds VM limit"

I changed the JVM size from 1 GB to 2 GB in
cassandra/bin/cassandra.in.sh. But, the error still persists.

Any help will be much appreciated.
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Gautam