When it comes to optimizing the performance of your Postgres database, there are some simple yet essential steps you can take that will make all the difference. Whether you’re setting up a new database or already running it in production, this guide will help you prepare your Postgres for better performance troubleshooting. In just five minutes, you’ll have everything in place to ensure smooth and efficient database operations.
1. Record Queries with pg_stat_statements
The pg_stat_statements is a powerful tool that records and parameterizes queries and provides critical information about their execution. You’ll be able to see how long each query takes to run, how often it’s executed, and more. With pg_stat_statements, you can answer questions such as:
- Which queries take the most cumulative time to execute
- Which queries are run the most frequently
- The average execution time of each query
To enable this feature, simply run the following query:
CREATE EXTENSION pg_stat_statements;
2. Log Slow Queries
Postgres can automatically log slow queries into your standard logs, and you can specify the threshold for slow queries. For most web applications, a threshold of 100 milliseconds or 1 second is recommended. To set the threshold, use the following command:
ALTER DATABASE us SET log_min_duration_statement = '1s';
3. Log Explain Plans for Slow Queries
With the auto_explain feature, you can log the explain plan for slow queries, which provides valuable insights into their execution. You can use tools like despez EXPLAIN or HypoPG to analyze the explain plans and identify performance bottlenecks. To enable auto_explain, run the following query:
ALTER SYSTEM SET session_preload_libraries = 'auto_explain'; SELECT pg_reload_conf();
Next, set your configuration for auto_explain to log all queries over 2 seconds:
ALTER SYSTEM SET auto_explain.log_min_duration = 2000; ALTER SYSTEM SET auto_explain.log_analyze = on; ALTER SYSTEM SET auto_explain.log_triggers = on; ALTER SYSTEM SET auto_explain.log_nested_statements = on; SELECT pg_reload_conf();
4. Kill Long Running Queries
Postgres has the ability to automatically kill long-running queries, which can prevent other performance issues from affecting your customers. You can set a statement timeout for queries that run longer than your specified threshold. To set the statement timeout, use the following command:
ALTER DATABASE mydatabase SET statement_timeout = '30s';
With these simple steps in place, you’ll be prepared for any performance troubleshooting that may arise.
In conclusion, there are several steps you can take to improve the performance of your Postgres database. By enabling pg_stat_statements, logging slow queries, logging explain plans for slow queries, and killing long-running queries, you’ll be able to quickly identify and resolve performance issues. With pg_stat_statements, you’ll be able to see which queries are taking the most time to execute, which ones are run the most frequently, and how long they take on average to execute. Logging slow queries and the explain plans for slow queries will provide you with the information you need to make changes to improve performance. And by setting a statement timeout, you can prevent long-running queries from impacting other areas of your database. By implementing these simple steps, you’ll be well on your way to improving the performance of your Postgres database and ensuring that it runs smoothly.
If you have any suggestions on the further improvements on postgres, feel free to drop them the comments below 🙂
If you liked this article, you might also like a case study that I published. Optimizing Geospatial Search with PostgreSQL Geospatial Indexing.