What's Changed

New features

• After the Pika slave instance executes slaveof no one to remove the replication relationship with the master node, the slaveof information is persisted into the configuration file. #2973 @cheniujh
• Added support for backup and recovery in master-slave mode for Pika-Operator. #2968 @buzhimingyonghu
• Added the log-net-activities parameter in the configuration file to dynamically enable or disable the logging of certain connection-related activities. This can be adjusted with config get/set. #2964 @cheniujh
• Added the repl_connect_status metric to Pika info and integrated it into pika_exporter to facilitate monitoring of the replication status. #2961 @cheniujh
• Upgraded kubeblocks to version 0.9, improving and optimizing Pika-Operator to simplify code and support instance scale-down. #2860 @XiaoLiang2333
• Pika-Operator now supports starting in master-slave mode. See the README document for more details. #2903 @XiaoLiang2333
• Added keyspace_hits and keyspace_misses metrics to pika_exporter, enabling users to monitor key hit rates. #2579 @chenbt
• RedisCache now avoids storing large keys to prevent excessive memory usage or the eviction of frequently accessed hot keys, which could impact performance. #2557 @QlQlqiqi
• Solved the problem of consistency between Pika database and cache #3034 #3037 @Mixficsol
• The statistics on Pika time in each period, RocksDB execution time, lock acquisition time, Binlog write time, and Redis-Cache read time are increased #3036 @wangshao1
• Fixed version information viewing for Pika, Pika_exporter, Codis components #3054 #3057 @Mixficsol
• Added the Auth command to manage the command thread pool #3048 @Mixficsol
• The maximum number of elements in RedisCache and the size of all Key types can be updated to the threshold of Redis-Cache by using the configuration file and dynamically modified by using the Config command #3043 #3047 @Mixficsol

Improvement

• Pika now supports dynamically modifying the max-subcompactions parameter to optimize the compact operation for L0 layers at runtime. #2965 @cheniujh
• Improved the log-retention-time parameter to dynamically adjust the number of days for log retention. #2963 @cheniujh
• Moved the Pika-Migrate code to the tools folder to simplify binary compilation in different environments for data migration. #2941 @chenbt-hz
• Added Go tests for Pika complex data types and management commands to ensure service stability. [#2840](https://github.com/OpenAtomFoundation
• Updated the actions/checkout in GitHub Actions workflow to v5 for enhanced security and performance. #2833 @baerwang

Bugfix

• Fixed the rpoplpush command cache update issue, which caused inconsistency between the database and cache. #2976 @cheniujh
• Fixed compatibility issues between different versions of Pika-Exporter, which caused excessive logging and wasted disk resources. #2971 @buzhimingyonghu
• Adjusted the log level of slowlog to INFO to address the issue of triple logging, which consumed excessive disk space. #2948 @buzhimingyonghu
• Improved CI stability by resolving specific failure issues. #2937 @chejinge
• Fixed an issue where Pika instances could not set administrator passwords independently. #2920 @

📒 Documentation: PikiwiDB

Full Changelog: https://github.com/OpenAtomFoundation/pika/compare/v4.0.1...v4.0.2 Thanks to @007gzs, @baerwang , @cheniujh , @buzhimingyonghu , @chejinge , @Mixficsol , @QlQlqiqi , @chenbt-hz , @XiaoLiang2333, @wangshao1, @pro-spild and @tsinow for making this release possible.