We user AWS RDS Proxy to connect postgres database from Spring Boot.I assume RDS proxy is configured with session pooling.
As RDS proxy is alternative for pgBouncer Spring boot application doesn't worry about connection pool. So it uses SimpleDriverDataSource
It looks like RDS proxy doesn't share the connections between the DB users. Because when I look at pg_stat_activity my spring boot holds many connections even after the restart. This is understandable that rds proxy hold connections rather than the application. Also the client count is zero in RDS proxy metrics. Does it mean RDS proxy never share the connections in the connection pool with other user?
It makes depriving of connections for other applications.
Is there configurations in RDS proxy to release connection to solve this ?
Related
I connect my DB (AWS RDS) to Spring boot JPA, Then my number of connections increases dramatically.
it is 12 now, I think it works spring boot 5 + browser 5, workbench 1 +, and others?
How can I reduce my number of connections? How can I maintain this connection safely?
You should be looking for Database connection pooling.
Database connection pooling is a method used to keep database connections open so they can be reused and also it will be keeping the total number of connections within a limit that we are specifying.
The default connection pool in Spring Boot is HikariCP, all you have to do is configure it properly
Sample connection pool configuration,
spring.datasource.hikari.connection-timeout = 20000
spring.datasource.hikari.minimum-idle= 10
spring.datasource.hikari.maximum-pool-size= 10
spring.datasource.hikari.idle-timeout=10000
spring.datasource.hikari.max-lifetime= 1000
spring.datasource.hikari.auto-commit =true
I need to configure a failover cluster for Postgres. I want to use PgPool-II as failover for the failed instance of DB.
My application runs on Spring Boot 2 and uses HikariCP as datasource. HikariCP is a connection pool by itself, and PgPool uses its connection pool.
HikariCP allocate connection pool from PgPool, which gives connections from it's own pool. I understand that PgPool pool size must be greater than Hikari pool.
Can they work together? And is this a good practice to use both of them in conjuction?
I am creating microservices applications using spring boot. All these microservices will connect to a single database AWS Aurora Serverless. I am planning to configure the connection pooling in my applications using HikariCP. Based on my initial research, Aurora Serverless manages connection pooling automatically. My question are the following.
Do I still need to configure connection pooling in my microservices using HikariCP? If yes, what is the recommended configuration in spring boot application.yml considering these are microservices that would share the same database?
If connection pooling configuration is not needed in my microservices, should i disable it? And, how should I do it my application.yml.
I have initial hikaricp configuration as shown in my code below
Springboot version is 1.5.7.RELEASE
application.yml
spring:
datasource:
type: com.zaxxer.hikari.HikariDataSource
hikari:
connection-timeout: 30000
minimum-idle: 30
maximum-pool-size: 200
idle-timeout: 30000
... database details (url, password, etc...)
A connection pool is still useful since there will be a cost to build a connection from your app to their connection pool.
What is different is that when you don't have any activity during a significant amount of time (night/weekend/periods of no activity) or when speed is not a necessity you should put the minimum-idle parameter to zero.
This will make sure the number of connections goes down to zero and enable your aurora serverless db to go into pause.
When it is paused you pay only for storage costs.
I am troubleshooting an issue with a Spring Boot app connecting to a PostgreSQL database. The app runs normally, but under fairly moderate load it will begin to log errors like this:
java.sql.SQLException: Timeout after 30000ms of waiting for a connection.
This is running on an Amazon EC2 instance connecting to a PostgreSQL RDS. The app is configured like the following:
spring.datasource.url=jdbc:postgresql://[rds_path]:5432/[db name]
spring.datasource.username=[username]
spring.datasource.password=[password]
spring.datasource.max-active=100
In the AWS console, I see 60 connections active to the database, but that is across several Spring Boot apps (not all this app). When I query the database for current activity using pg_stat_activity, I see all but one or 2 connections in an idle state. It would seem the Spring Boot app is not using all available connections? Or is somehow leaking connections? I'm trying to interpret how pg_stat_activity would show so many idle connections and the app still getting connection pool time outs.
Figured it out. Spring is using the Hikari database connection pooling (didn't realize that until after more closely inspecting the stack trace). Hikari configuration parameters have different names, to set the pool size you use maximum-pool-size. Updated that and problem solved.
What's the difference between MysqlConnectionPoolDataSource and C3p0, BoneCP or dbcp library for connection pooling? I don't understand why use a library if mysql connector give connection pooling.
A ConnectionPoolDataSource is not a connection pool (or at least: it shouldn't be), it is intended to be used by a DataSource that provides pooling (eg from an application server). A ConnectionPoolDataSource provides the physical connections that will be held in the connection pool. Besides creating those physical connections a ConnectionPoolDataSource shouldn't do anything else.
So if you are working in an application server, use the pooling provided by the DataSources of the application server. If you are in a standalone application or a server that doesn't provide datasources on its own, use third party connection pools like BoneCP, c3p0 or Apache DBCP. If MySQL also provides a normal DataSource that provides pooling, then you could use that.