* (feature)(cloud) Use dynamic allocator instead of static buffer pool for better elasticity. (#28983)
* [fix](outfile) Fix unable to export empty data (#30703)
Issue Number: close#30600
Fix unable to export empty data to hdfs / S3, this behavior is inconsistent with version 1.2.7,
version 1.2.7 can export empty data to hdfs/ S3, and there will be exported files on S3/HDFS.
* [fix](file-writer) avoid empty file for segment writer (#31169)
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Co-authored-by: AlexYue <yj976240184@gmail.com>
Co-authored-by: zxealous <zhouchangyue@baidu.com>