[ASTERIXDB-2361] Memory Leak Due to Netty Close Listeners

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 0.9.3
• Fix Version/s: 0.9.4.1
• Component/s: HYR - Hyracks
• Assignee: Murtadha Makki Al Hubail
• Reporter: Till Westmann
• Created: 10/Apr/18 00:05
• Updated: 10/Apr/19 18:33
• Resolved: 10/Apr/19 18:33

Description

Currently, each ChunkedResponse object creates a PrintWriter that allocates 8K for its StreamEncoder. There is a channel close listener that is registered in ChunkedNettyOutputStream that prevents the ChunkedResponse from being garbage collected until the request connection is closed. However, if the connection keepAlive is set, the connection will not be closed until the client decides to close it and therefore the ChunkedResponse can't be garbage collected until then. We need to revisit registering the close listeners and ensure all request based resources can be released as soon as the response is closed.