Skeena: Efficient and Consistent Cross-Engine Transactions

Skeena enables consistent ACID cross-engine transactions over two database engines (e.g., storage-centric InnoDB and memory-optimized ERMIA, both in MySQL) without intrusive changes to individual engines.

This repository implements Skeena. See details in our SIGMOD 2022 paper below. If you use our work, please cite:

Skeena: Efficient and Consistent Cross-Engine Transactions.
Jianqiu Zhang, Kaisong Huang, Tianzheng Wang and King Lv.
ACM SIGMOD/PODS International Conference on Management of Data 2022

The implementation integrates the ERMIA (SIGMOD 2016) main-memory database engine into MySQL alongside with its default InnoDB engine to enable cross-engine transactions.

Directory structure and notable source files:

• mysql/ - modified MySQL to support ERMIA and Skeena
• mysql/storage/innobase/trx/trx0trx.cc - modified InnoDB transaction code for snapshot selection
• mysql/sql/gtt.{h,cc} - core Skeena implementation

Build ERMIA:

• Follow sample instructions in ermia/README.md

Build MySQL:

• Follow sample instructions under mysql/ermia-contrib/BUILD

Environment:

• MySQL settings: follow the mysql/ermia-contrib/my.cnf file and put it in your ~/.my.cnf
• Useful variables in my.cnf:
  • ermia-ermia-log-dir: Path to the ERMIA engine log dir
  • ermia-gtt-recycle-capacity: The size of each GTT(CSR) Tree
  • ermia-gtt-recycle-threshold: The threshold to trigger the recycle
• To start MySQL Server: ./build/bin/mysqld

Experiments:

• All scripts are stored under mysql/ermia-contrib
  • Microbenchmark: see the mysql/ermia-contrib/skeena-benchrunner folder
  • TPC-C: see ermia-contrib/tpcc/README and check the scripts there