![]() Now you can take the statement and analyze why it is slow. When we inspect the logfile, we already see the desired entry: In my example I use pg_sleep to just make the system wait for 10 seconds. You are now connected to database "test" as user "hs". Postgres=# ALTER DATABASE test SET log_min_duration_statement = 5000 ĪLTER DATABASE allows you to change the configuration parameter for a single database. Therefore it can make sense to make the change only for a certain user or for a certain database: In many cases you want to be a lot more precise. If you change nf, the change will be done for the entire instance, which might be too much. You can do this using an init script or simply by calling the SQL function shown above. If you change this line in nf there is no need for a server restart. If you set log_min_duration_statement in nf to 5000, PostgreSQL will consider queries which take longer than 5 seconds to be slow queries and send them to the logfile. You have version choices: If you want to turn the slow query log on globally, you can change nf: In a default configuration the slow query log is not active. This way, slow queries can easily be spotted so that developers and administrators can quickly react and know where to look. ![]() The idea is: If a query takes longer than a certain amount of time, a line will be sent to the log. Making use of the PostgreSQL slow query log – method 1Ī more traditional way to attack slow queries is to make use of PostgreSQL’s slow query log. Rely on aggregate information in pg_stat_statementsĮach method has its own advantages and disadvantages, which will be discussed in this document.Check execution plans with auto_explain.Here are my top three suggestions to handle bad performance: However, three methods have proven to be really useful to quickly assess a problem. There are many ways to approach performance problems. Finding slow queries in PostgreSQL and pinpointing performance weak spots is therefore exactly what this post is all about. (Last updated ) When digging into PostgreSQL performance, it is always good to know which options one has to spot performance problems, and to figure out what is really happening on a server. ![]() Performance pg_stat_statements postgresql query query performance statistics
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |