What is Pstress?

Pstress is an open-source, probability-based database testing tool designed to simulate concurrent workloads and test database recovery under failure conditions. It generates random SQL transactions based on user-provided options, allowing you to test features, regression, and crash recovery. It can stress-test a single server or a cluster with multi-threaded workloads.

Pstress consists of two main components:

• Workload Module: A multi-threaded C++ program that creates random metadata and SQL queries to execute.
• Driver Script: A Bash script that manages concurrency and crash recovery testing by integrating with the workload module.

What’s New in Pstress?

• Flexible Execution: Run Pstress standalone against an active server or use the driver script with a configuration file. With the script, the server starts automatically, and Pstress executes with options from the config file. The script stops the server after a set time, saves the data directory, restarts with varied settings, and resumes the load—each cycle is called a “step.”
• Concurrent Load: During each step, multiple threads execute diverse SQL combinations across separate connections.
• Crash Recovery Testing: After each step, Pstress performs crash recovery using the previous step’s data directory.
• Customizable Workloads: Generate anything from single-threaded INSERTs to complex multi-threaded transactions, depending on your options.
• Server Failure Simulation: Force a shutdown or kill the server to test recovery.
• Detailed Logging: Issues are logged in Pstress run logs. By default, each trial saves the data directory, server error logs, thread logs, binaries, and configuration file.

How to Build Pstress?

1. Prerequisites: Install CMake (version 2.6 or higher), a C++ compiler (GCC 4.7+ or equivalent), and development files for MySQL or DuckDB. You may also need OpenSSL or other dependencies based on your setup.
2. Navigate: Change to the pstress directory.
3. Run CMake: Use the appropriate options:
   • -DMYSQL=ON: Build Pstress with MySQL support.
   • -DDUCKDB=ON: Build Pstress with DuckDB support.
   • Add -DSTATIC_LIBRARY=OFF for dynamic linking (default is dynamic).
4. Custom Paths: If MySQL or DuckDB is in a non-standard location, set:
   • -DMYSQL_INCLUDE_DIR and -DMYSQL_LIBRARY (for MySQL).
   • -DDUCKDB_INCLUDE_DIR and -DDUCKDB_LIBRARY (for DuckDB).
   • Or use -DBASEDIR to point to an extracted binary directory for automatic detection (recommended).
5. Binary Naming: The resulting binary gets a suffix:
   • pstress-ms for MySQL.
   • pstress-dd for DuckDB.

Example of compiling pstress with MySQL

cd pstress
mkdir bld && cd bld
cmake .. -DMYSQL=ON -DMYSQL_LIBRARY=$MYSQL_BUILD_DIR/library_output_directory/libmysqlclient.so -DMYSQL_INCLUDE_DIR=$EXTERNAL_OUTPUT_DIRECTORY/include
make

Example of compiling pstress with Duckdb

cd pstress
mkdir bld2 && cd bld2
cmake .. -DDUCKDB=ON -DDUCKDB_LIBRARY=$DUCKDB_BUILD_DIR/src/libduckdb.so -DDUCKDB_INCLUDE_DIR=$DUCKDB_BUILD_DIR/src/include
make

Help Section

First, take a quick look at ./pstress-dd --help --verbos, ./pstress-ms --help --verbose to see available modes and options.

Example of commad to run pstress

pstress-ms --table=1 --column=10 --seconds=10 --threads=10 --socket=$SOCKET

Contributors

• Alexey Bychko - C++ code, cmake extensions
• Roel Van de Paar - invention, scripted framework
• Rahul Malik - pstress developer
• Mohit Joshi - pstress developer
• For the full list of contributors, please see CONTRIBUTORS