[CASSANDRA-884] get_range_slice returns multiple copies of each row for ConsistencyLevel > ONE

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 0.6

Environment

4-cluster Gentoo Linux 2.6.18 with a ReplicationFactor of 2

• Severity: Normal
• Assignee: Omer van der Horst Jansen
• Reporter: Omer van der Horst Jansen

Authors

Omer van der Horst Jansen

• Created: 12/Mar/10 20:50
• Updated: 16/Apr/19 09:33
• Resolved: 19/Mar/10 20:36

Description

I've noticed that both 0.5.1 and 0.6b2 return multiple identical copies of the data stored in my keyspace whenever I make a call to get_range_slice or get_range_slices using
ConsistencyLevel.QUORUM and ReplicationFactor is greater than one.

So with ReplicationFactor set to 2 for my application's KeySpace I get double the number of KeySlices that I expect to get. When using ConsistencyLevel.ONE I get only one KeySlice for each row.

I've seen this happen with Cassandra 0.5.1 and with 0.6 beta 2. The behavior on 0.6 beta 2 is exhibited with both get_range_slice and get_range_slices.

The attached Java program demonstrates the issue for 0.6 beta 2. The program writes a series of single-column rows into the Standard1 table, and then uses get_range_slice to receive a list of all row. The returned number of rows is consistently twice the number of rows written to the database. I wipe out the database completely before running the test.