How can I check which tables app requests are hitting?

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vkayanala_42513 asked May 7, '20 Erick Ramirez answered May 7, '20

How can I check which tables app requests are hitting?

Hello DS Community,

I'm facing hard to find which keyspace/table being hit more while cluster is under load.

Is there any tool or logging which can give numbers of read and write requests going to? and how Opscenter get the stats of application requests in Cassandra?

We are using OpsCenter, and added dashboard of TBL: Local Read requests to a specific keyspace.table but it's not showing any number on it. It would be grate if we have straight forward commands that will give all these numbers for specific timeline.

Please help me.

-Varun

cassandra

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Answer 1 · 2020-05-07T22:39:31Z

Erick Ramirez answered May 7, '20

@vkayanala_42513 You won’t be able to see the queries coming through to the cluster unless you have audit logging enabled.

If you are collecting slow queries, it might give you some idea on which tables are problematic but it’s not a direct correlation to the most accessed tables. It’s more a side-effect since queries start to slow down when nodes are under load.

As a last resort, you can monitor the local read count in the output of nodetool tablestats. There isn’t an out-of-the-box solution for it so you’ll need to write a script of some sort to make it easier to track it over a certain period. Cheers!

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