[GEODE-7814] Unnecessary Object Allocations in DistributionMessage

• Type: Bug
• Status: Closed
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 1.12.0, 1.13.0
• Component/s: membership
• Labels: GeodeCommons
• Assignee: Ernest Burghardt
• Reporter: Juan Ramos
• Created: 25/Feb/20 11:34
• Updated: 30/Mar/20 23:34
• Resolved: 27/Feb/20 09:42

Description

The DistributionMessage class unnecessary allocates instances of java.util.Collection$SingletonList and InternalDistributedMember[] through the attributes EMPTY_RECIPIENTS_ARRAY and ALL_RECIPIENTS_LIST.
These attributes are final and only used to execute internal comparisons but, since they are not declared as static, every instance of DistributionMessage will have its own instance, generating unnecessary garbage.
Using one of our internal testing scenarios and a java profiler we detected that, under the current develop branch, we create 14.824 and 11.212  more instances of java.util.Collection$SingletonList and InternalDistributedMember[] than when using Geode 1.10.
The increase in the memory footprint is not much (around 1MB all together), and the time spent on this operation is around 1.5 seconds slower overall (screenshots attached).

Issue Links

• links to: GitHub Pull Request #4731