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debasis.tcs_69445 avatar image
debasis.tcs_69445 asked ·

Slowness observed during load test

We are seeing some queries are appearing in debug.log and our memory and CPU got saturated during the load test.

<SELECT * FROM cam.cam_counter WHERE target = U-Son0048004168 LIMIT 5000>, time 1610 msec - slow timeout 500 msec/cross-node
<SELECT * FROM cam.cam_counter WHERE target = U-Son0048004730 LIMIT 5000>, time 1010 msec - slow timeout 500 msec

Table definition:-


CREATE TABLE IF NOT EXISTS cam_counter (
    target text,
    counter text,
    zoneid text,
    value int,
    last_updated_timestamp bigint,
    expiry_timestamp bigint,
    PRIMARY KEY(target, counter, zoneid)
) WITH gc_grace_seconds=3600;

We are using Cassandra 3.11.5 open source.

We have 11 nodes C* cluster with single data center. We are using SSD storage.

Can you please suggest what might be the problem?

performance
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1 Answer

Erick Ramirez avatar image
Erick Ramirez answered ·

What you're seeing is that your nodes are getting overloaded so it is expected that queries will be slow.

You will need to throttle your load test if you don't like seeing the nodes get overloaded. Cheers!

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