[CASSANDRA-15318] sendMessagesToNonlocalDC() should shuffle targets

• Type: Improvement
• Status: Resolved
• Priority: Normal
• Resolution: Fixed
• Fix Version/s: 4.0-alpha3, 4.0
• Component/s: Messaging/Internode
• Change Category: Quality Assurance
• Complexity: Normal
• Platform: All

Source Control Link

https://github.com/dineshjoshi/cassandra/commit/311891f35e538f4a8be0309f6d7045fef59dee71

Test and Documentation Plan

Jon's added tests.

• Assignee: Jon Meredith
• Reporter: Jon Meredith

Authors

Jon Meredith

Reviewers

Dinesh Joshi

• Created: 08/Sep/19 21:34
• Updated: 18/Jul/22 21:20
• Resolved: 19/Nov/19 19:25

Description

To better spread load and reduce the impact of a node failure before detection (or other issues like issues host replacement), when forwarding messages to other data centers the forwarding non-local dc nodes should be selected at random rather than always selecting the first node in the list of endpoints for a token.
 

Issue Links

• fixes: CASSANDRA-11170 Uneven load can be created by cross DC mutation propagations, as remote forwarding node is not randomly picked