[CASSANDRA-18697] Skip ColumnFamilyStore#topPartitions initialization when client or tool mode

• Type: Bug
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.1.4
• Component/s: Tool/bulk load
• Bug Category: Correctness - API / Semantic Implementation
• Severity: Low
• Complexity: Low Hanging Fruit
• Discovered By: Adhoc Test
• Platform: All
• Since Version: 4.1.0

Source Control Link

https://github.com/apache/cassandra/commit/9c796dfb272daa3ce57a2dc5cbeadd9273e1ac72

Test and Documentation Plan

Added a unit test that showcases the issue

• Assignee: Francisco Guerrero
• Reporter: Francisco Guerrero

Authors

Francisco Guerrero

Reviewers

Dinesh Joshi, Yifan Cai

• Created: 26/Jul/23 17:19
• Updated: 01/Aug/23 22:03
• Resolved: 01/Aug/23 20:26

Description

In org.apache.cassandra.db.ColumnFamilyStore the topPartitions is initialized when the keyspace is not a system keyspace. However, when running the cassandra library as client mode or tool mode, the initialization also happens. However, TopPartitionTracker performs queries to the system keyspace, which might not be available in most of the cases. For that reason, we should skip initialization of topPartitions when running on client mode or tool mode.

In utilities and external libraries, this can produce a warning that is displayed with a stack trace. This warning can be misleading for end users, and can cause confusion. But more importantly, the initialization of topPartitions is not required in this mode.

The warning is similar to this:

    WARN org.apache.cassandra.db.SystemKeyspace: Could not load stored top SIZES partitions for ...
    org.apache.cassandra.db.KeyspaceNotDefinedException: keyspace system does not exist
            at org.apache.cassandra.schema.Schema.validateTable(Schema.java:xxx) ~[?:?]
            at org.apache.cassandra.cql3.statements.SelectStatement$RawStatement.prepare(SelectStatement.java:xxx) ~[?:?]
            at org.apache.cassandra.cql3.statements.SelectStatement$RawStatement.prepare(SelectStatement.java:xxx) ~[?:?]
            at org.apache.cassandra.cql3.statements.SelectStatement$RawStatement.prepare(SelectStatement.java:xxx) ~[?:?]
            at org.apache.cassandra.cql3.QueryProcessor.parseAndPrepare(QueryProcessor.java:xxx) ~[?:?]
            ... 

Issue Links

• links to: GitHub Pull Request #2519
• links to: GitHub Pull Request #2535