The first thing that comes to mind is to look into the caching options that HBase provides, unfortunately I am not too familiar with them to give more detail.
Sidenote: The general recommendation for urgent performance matters is to contact the account team, perhaps they can arrange specialist knowledge to be available. Or if you are already connected to someone from the Proffesional Services organization, they may be able to help you with an in depth analysis.
- Dennis Jaheruddin
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