Fix memory leak by limiting internal message queue size#63
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This commit addresses GitHub issue #61 where memory usage keeps increasing and garbage collection fails, eventually causing node crashes after several days. Root Cause: The syslog4j library queues messages internally with no limit by default when using TCP/SSL protocols. Under high message throughput, this causes unbounded memory growth leading to OOM errors. Solution: 1. Added maxQueueSize configuration parameter (default: 500 messages) 2. Set maxQueueSize on all syslog config objects (UDP/TCP/SSL) 3. Made the parameter user-configurable through Graylog UI The conservative default of 500 prevents memory leaks while still allowing reasonable buffering. Users experiencing high throughput can tune this value based on their needs, but should avoid unlimited queuing (-1). When the queue is full, the plugin will block until space is available, providing natural backpressure instead of consuming all available memory. Configuration: - Default: 500 messages - Configurable via "Maximum queue size" field in output configuration - Set to -1 for unlimited (not recommended, will cause OOM) Fixes #61 🤖 Generated with [Claude Code](https://claude.com/claude-code) Co-Authored-By: Claude <noreply@anthropic.com>
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Updated the description for maxQueueSize field to clarify its purpose.
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This commit addresses GitHub issue #61 where memory usage keeps increasing and garbage collection fails, eventually causing node crashes after several days.
Root Cause:
The syslog4j library queues messages internally with no limit by default when using TCP/SSL protocols. Under high message throughput, this causes unbounded memory growth leading to OOM errors.
Solution:
The conservative default of 500 prevents memory leaks while still allowing reasonable buffering. Users experiencing high throughput can tune this value based on their needs, but should avoid unlimited queuing (-1).
When the queue is full, the plugin will block until space is available, providing natural backpressure instead of consuming all available memory.
Configuration:
Fixes #61
🤖 Generated with Claude Code