v2.4.0-release-note_en.txt

The main modifications of V2.4.0-release version focus on:
1. Distributed computing performance improvement:
● hasAggs/having/sort/limit/Stable function/ is optimized and pushed down to DN for execution, improving performance by nearly a hundred times.
● Distributed process ProcLock segmented lock optimization reduces lock conflicts and increases execution efficiency by approximately 5 times.
● Execution plan optimization: When the number of redistributed nodes is 1, the remote operator is skipped and the execution plan is streamlined.

2. 2PC transaction optimization:
● Deadlock check performance optimization: obtain gxid in batches; change traversal search gxid to binary search; increase try round limit.
● 2PC adds a protection mode to prevent partial submission.
● drop database adds a prepare process to ensure that no node failure remains.

3. Enhanced ease of use:
● Added pooler multi-thread logging function to facilitate problem analysis by users.
● GTM log optimization, logs are aggregated into one file, and active logs are automatically split, making it easier for users to view at any time.
● Supports gtm_ctl -l to specify the log file path to start, making it convenient for users to manage logs.

4. New feature support:
● Self-developed partition table pruning, adding IN syntax pruning, accelerating pruning in advance.
● Data shuffle supports user-defined functions.
● Allow deletion of columns of the main table with distributed foreign key constraints.