wang-jiahua opened a new issue, #11002: URL: https://github.com/apache/rocketmq/issues/11002
### Before Creating the Enhancement Request - [x] I have confirmed that this should be classified as an enhancement rather than a bug/feature. ### Summary Cache the topic bytes in `MessageExtEncoder` and the CRC32 property-key bytes in `MessageDecoder` to avoid two per-message `String.getBytes()` allocations on the broker write path. ### Motivation - `MessageExtEncoder.encode()` / `encodeWithoutProperties()` call `msgInner.getTopic().getBytes(UTF_8)` for every message. Broker traffic is highly repetitive per thread, and the encoder instance is already `ThreadLocal`, so the same topic string is re-encoded over and over. - `MessageDecoder.createCrc32()` re-encodes the constant property key `MessageConst.PROPERTY_CRC32` on every message when CRC32 stamping is enabled. ### Solution - `MessageExtEncoder`: keep a single-slot `cachedTopic`/`cachedTopicData` pair (no synchronization needed — the encoder is `ThreadLocal`). Hit returns the cached bytes; miss falls back to `getBytes` and refreshes the slot, so mixed-topic traffic is never worse than today apart from one string comparison. - `MessageDecoder`: pre-encode `PROPERTY_CRC32` into a `private static final byte[]`. ### Verification - `AppendCallbackTest` 4/4, `AppendPropCRCTest` 2/2 (covers the CRC32 constant path), `LmqDispatchTest` 5/5, `CompactionLogTest` 4/4, `MessageDecoderTest` 7/7; checkstyle clean. - 4-node cluster A/B (256-thread sync producer, 1KB, per-arm clean store + restart): broker TPS and young GC per million messages are flat versus baseline — the saving (one short `byte[]` per message) is below GC-count resolution at this load, so this is a cleanup-level allocation reduction, not a measurable throughput win. -- This is an automated message from the Apache Git Service. To respond to the message, please log on to GitHub and use the URL above to go to the specific comment. To unsubscribe, e-mail: [email protected] For queries about this service, please contact Infrastructure at: [email protected]
