netty5/codec-mqtt
Francesco Nigro 319a4bc3ba Reduce garbage on MQTT (#10509)
Reduce garbage on MQTT encoding

Motivation:

MQTT encoding and decoding is doing unnecessary object allocation in a number of places:
- MqttEncoder create many byte[] to encode Strings into UTF-8 bytes
- MqttProperties uses Integer keys instead of int
- Some enums valueOf create unnecessary arrays on the hot paths
- MqttDecoder was using unecessary Result<T>

Modification:

- ByteBufUtil::utf8Bytes and ByteBufUtil::reserveAndWriteUtf8 allows to perform the same operation GC-free
- MqttProperties uses a primitive key map
- Implemented GC free const table lookup/switch valueOf
- Use some bit-tricks to pack 2 ints into a single primitive long to store both result and numberOfBytesConsumed and use byte[].length to compute numberOfByteConsumed on fly. These changes allowed to save creating Result<T>.

Result:
Significantly less garbage produced in MQTT encoding/decoding
2020-09-04 18:31:53 +02:00
..
src Reduce garbage on MQTT (#10509) 2020-09-04 18:31:53 +02:00
pom.xml Correcting Maven Dependencies (#8622) 2018-12-06 09:02:00 +01:00