bk_server_rocksdb_rowcache_example.conf

# Example configuration for enabling RocksDB row cache in BookKeeper
# This configuration demonstrates how to enable row cache for improved read performance

# Use DbLedgerStorage (required for RocksDB features)
ledgerStorageClass=org.apache.bookkeeper.bookie.storage.ldb.DbLedgerStorage

# RocksDB Block Cache Configuration
# Block cache caches compressed/uncompressed blocks
# Default: 10% of direct memory / number of ledger directories
# dbStorage_rocksDB_blockCacheSize=536870912  # 512MB

# RocksDB Row Cache Configuration (NEW)
# Row cache stores actual key-value pairs for faster lookups
# This avoids SST file reads for frequently accessed keys
# Default: 0 (disabled)
# Recommended values: 64MB to 512MB depending on available memory
dbStorage_rocksDB_rowCacheSize=268435456  # 256MB

# Memory allocation example for a server with 8GB RAM:
# - Write cache: 25% of direct memory (~2GB)
# - Read-ahead cache: 25% of direct memory (~2GB)
# - Block cache: 10% of direct memory (~800MB)
# - Row cache: 256MB (configured above)
# - Total RocksDB memory usage: ~5GB

# Other RocksDB tuning parameters
dbStorage_rocksDB_writeBufferSizeMB=64
dbStorage_rocksDB_sstSizeInMB=64
dbStorage_rocksDB_blockSize=65536
dbStorage_rocksDB_bloomFilterBitsPerKey=10

# Enable compression for better storage efficiency
dbStorage_rocksDB_lz4CompressionEnabled=true

# Note: Row cache is most effective for:
# - Hot keys that are accessed frequently
# - Small to medium-sized values
# - Read-heavy workloads
# - Low-latency requirements (sub-millisecond reads)