Optimizing Memory Management in Percona Server for MySQL with RocksDB Configuration

To configure the rocksdb_strict_capacity_limit and rocksdb_soft_pending_compaction_bytes_limit variables in Percona Server for MySQL for memory management:

1. rocksdb_strict_capacity_limit: This variable, when enabled, enforces a strict limit on the amount of memory RocksDB can use. Set it in the MySQL configuration file like so:

    rocksdb_strict_capacity_limit=1
   

   Enabling this can help avoid out-of-memory scenarios, but it may also cause write stalls if the limit is reached.

2. rocksdb_soft_pending_compaction_bytes_limit: This variable sets a soft limit on the size of compaction. When this limit is approached, RocksDB tries to slow down write operations to allow compaction to catch up, helping to manage memory usage more efficiently. It can be set as follows:

    rocksdb_soft_pending_compaction_bytes_limit=2147483648  # Example value
   

   Adjust the value based on your server's memory capacity and workload.

Remember to restart the MySQL server after making these changes. It's crucial to monitor the server's performance after adjustments and tweak the settings as necessary based on observed behavior and resource utilization. For detailed configuration options and best practices, refer to the Percona Server for MySQL documentation.