[CASSANDRA-16078] Performance regression for queries accessing multiple rows

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Cannot Reproduce
• Fix Version/s: 4.0-rc1, 4.0
• Component/s: Consistency/Coordination
• Bug Category: Degradation - Performance Bug/Regression
• Severity: Critical
• Complexity: Normal
• Discovered By: Performance Regression Test
• Platform: All
• Assignee: Caleb Rackliffe
• Reporter: David Capwell

Authors

Caleb Rackliffe

• Created: 27/Aug/20 18:28
• Updated: 25/Feb/21 10:25
• Resolved: 27/Jan/21 17:19

Description

This is spin off from CASSANDRA-16036.

In testing 4.0 relative to 3.0* I found that queries which accessed multiple rows to have a noticeable performance decrease; two queries were used in the test (more may be impacted, others might not): query partition (table has clustering keys) with LIMIT, and query clustering keys using IN clause.

In the below graphs the green line is 3.0 and the other lines are 4.0 (with and without chunk cache)

Partition with LIMIT

Cluster with IN clause

Issue Links

• is related to: CASSANDRA-16036 Add flag to disable chunk cache and disable by default