Hello, The SQLA Pooling section <https://docs.sqlalchemy.org/en/20/core/pooling.html> says that the default connection pool (QueuePool is the default pool, isn’t it?) has 5 connections with an overflow of 10 (docs <https://docs.sqlalchemy.org/en/20/core/pooling.html#sqlalchemy.pool.QueuePool.__init__> ).
However, in our configuration we use *sqlalchemy.pool_recycle = 3600sqlalchemy.pool_pre_ping = Truesqlalchemy.pool_size = 20sqlalchemy.max_overflow = 30* Independently of how many connections the PG server accepts (looks like 100 by default, docs <https://www.postgresql.org/docs/current/runtime-config-connection.html>) a single gRPC server process has a global Engine instance with a connection pool of that configured size. Without too many requests flowing through our gRPC server process, we already see these errors: *QueuePool limit of size 20 overflow 30 reached, connection timed out, timeout 30.00 (Background on this error at: https://sqlalche.me/e/14/3o7r)* Assuming that we have the implementation correct (a global Engine and its connection pool, sessions fetching and releasing connections correctly) the error can mean one of two things: 1. too many simultaneous requests hold a connection too long; or 2. these settings aren’t realistic for a production server environment. Is there another angle I might be missing? What configuration settings would you recommend? Other than turning on debugging (docs <https://docs.sqlalchemy.org/en/20/core/pooling.html#sqlalchemy.pool.Pool.params.echo>) what tips do you have to debug the issue? Much thanks! Jens -- SQLAlchemy - The Python SQL Toolkit and Object Relational Mapper http://www.sqlalchemy.org/ To post example code, please provide an MCVE: Minimal, Complete, and Verifiable Example. See http://stackoverflow.com/help/mcve for a full description. --- You received this message because you are subscribed to the Google Groups "sqlalchemy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sqlalchemy+unsubscr...@googlegroups.com. To view this discussion on the web visit https://groups.google.com/d/msgid/sqlalchemy/0cdbdb8a-0cff-47f4-b0ca-fccd70ded2den%40googlegroups.com.
