What is the difference between "hikaricp.connections." and "jdbc.connections." meter names? I have a Spring Boot 2 application that is defaulting to the Hikari connection pool mechanism and I am tring to understand how to best monitor the database connections in production. After visualizing my metrics in Datadog, I am seeing a slight difference in the metric data for both hikariCP.connections.active and jdbc.connections.active.
Are the JDBC meter names duplicates? Should one be used over the other or does it not matter. I have been struggling to find more detailed documentation on this. Any help is much appreciated.
HikariCP is a connection pool and JDBC is the API for managing a connection.
So it can be thought that Spring thinks about separating connection-pool-manager metrics from connection metrics.
Related
I am trying to use EclipseLink JPA for a sample java application. I am trying to configure the connection pool related settings in the persistence.xml, but I could not find any suitable property for specifying the minimum Idle connections to be maintained in the connection pool. I was not able to find any details around this property or idle connection time out property in the Eclipselink documentation, here. Can someone please point me to the documentation links that I am looking for?
I am using spring boot hikari db pool to connect to an Oracle database (19C).
Our properties are as below:
spring.datasource.app.hikari.type=com.zaxxer.hikari.HikariDataSource
spring.datasource.app.hikari.minimumIdle=5
spring.datasource.app.hikari.maximumPoolSize=10
spring.datasource.app.hikari.idleTimeout=600000
spring.datasource.app.hikari.connectionTimeout=180000
spring.datasource.app.hikari.max-lifetime=60000
Our Database's AUD table is filling up due to constant logon logoff actions getting registered from the services every second.
I used solution from below question (to decrease minimumIdle and increase idleTimeout for long idle times), but it did not resolve the issue.
spring jdbc hikari connection pool - constantly logs on and off to database
Can somebody help in this case. Thanks in advance.
If you have not override datasource with different property name for hikaricp then use below properties
spring.datasource.type=com.zaxxer.hikari.HikariDataSource
spring.datasource.hikari.minimum-idle=5
spring.datasource.hikari.maximum-pool-size=10
spring.datasource.hikari.idle-timeout=600000
spring.datasource.hikari.connection-timeout=180000
spring.datasource.hikari.max-lifetime=60000
I have an app that is written in java spring.
It uses hibernate to handle connections to postgres DB.
I want to get the size of the connection pool, but it isn't defined on the app's hibernate configurations.
So I guess it uses hibernate default size, which is 1?
That sounds very low to me.
How can I be sure what is the size of connection pool?
I read that it is recommended to use third party manager for this, but I don't think it's in used also.
The problem setup is based on a webservice (Spring/Java, Tomcat7 and MySql) where every user gets their own database, hence each request needs their own connection. As all databases are created dynamically during runtime, configuring them statically before startup is not an option.
To optimise database connection usage, an implementation of a database connection pool would be great, right?
With Java/Spring: How would I create a connection pool for dynamic databases? I am a bit struck by the lack of clean options here!
Problem: Tomcat's Connection Pool (and as far as i understand C3P0 as well) treats each new DataSource instance as a whole new connection pool -> stack-reference
Is it a good idea to create a static datasource with a generic MySql connection (without specifing the database on connection) and use a connection pool with this datasource together with adapted SQL statements?
stack-reference
What about developing a custom persistent database based datasource pool? Any experience with performance here? Any advice? Any libraries that do that?
Or would it be feasable to workaround Tomcat's DataSource problem by creating Tomcat JNDI Datasources dynamically by manipulating it's context.xml dynamically from Java?
I can't believe that there aren't more plain/simple solutions for this. Grails/Hibernate struggles with this, Java/JDBC struggles with this, ... is it such a rare use-case to separate userdata on a user basis by creating user specific databases dynamically? If so, what would be a better setup?
EDIT
Another option is the suggestion from #M.Deinum to use a single configured datasource and dynamically hotswap it for the right connection ->M.Deinum Blog and stack-reference. How does that perform with a connection pool like the ones above?
I believe that HikariCP works without having to specify a single database.
Once the databases are created in runtime, you have to create the pools also in runtime. I am afraid the spring infrastructure is not giving you any help here, as it is tuned for the usual static use case.
I'd have a map of pools:
have a Map < connectionUrlString,List< c3poPool > > map
when requesting a connection, get the corresponding c3po pool from the map
and you can get the best of both worlds, since the real connection pool for each dynamically created database is handled by a c3po instance, but you can create new instances in runtime
This works as a low-level solution. If you want to go further, you can wrap this logic into a db connection provider, and register that as a "driver". This way any part of your application requests a new connection, you can just return one connection from the existing pools (and if a totally new connection is requested, create a new pool for that).
First than all, sorry for my english, i'm improving every day.
In my experience, I had a similar situation and it was resolve with spring framework. Let me explain you how you'd solve that question.
Make a spring config file with these characteristics:
a) A resource loader: This one is the responsible of load properties from configurations files or from database, those properties will be the appropriates to establish the database connection.
b) A pool database configuration parameterized with the properties that you'll load.
Create a locator class: In this class you'll need a HashMap
Use the multi context feature of spring: The idea is assign a code to every one connection that you establish and later load that connection like an application context with spring, then in the locator class, put in the map that context and use it as frequent as you need.
I think is you follow these steps, you can create dynamic pool or database connection as you want.
I am reading about Connections vs DataSources in Java and I have some questions. Is a DataSource really just a manager and an abstraction of a Connection (or multiple connections)?
From docs:
A factory for connections to the physical data source that this DataSource object represents. An alternative to the DriverManager facility, a DataSource object is the preferred means of getting a connection.
Actually, a DataSource is a provider of Connections and it has a variety of implementations which operate in different manners. Such as:
Basic implementation -- produces a standard Connection object
Connection pooling implementation -- produces a Connection object that will automatically participate in connection pooling. This
implementation works with a middle-tier connection pooling manager.
Distributed transaction implementation -- produces a Connection object that may be used for distributed transactions and almost always
participates in connection pooling. This implementation works with a
middle-tier transaction manager and almost always with a connection
pooling manager.
Connection is the connection :) DataSource is a manager of connections (pool of connections).
Data source is the source of your data, the connection is the driver.
DataSource is ill concept in its existing form as if it was meant to abstract interactions it should not return some SQL connection to interact with in the first place. Also it is overkill and XA is fantasy concept that some paid dearly for lack of reliable implementation in the world (I mean all enterprise commercial implementers simply fail and expose business... someone got hurt because of it in finance, but I will not mention names). In general, regardless if Sun or Oracle recommends it, it results in over-engineering and some technical dirt in code (dealing with contexts, extra steps to get to data, some external configurations... and in the end it is still specific to vendor implementations anyway). Some developed coroporate solutions that deal with pooling, connection recovery e.t.c much better based on plain connections and DriverManager than DataSource implemtations provided by enterprise DBMS vendors.
For the record I worked with both and I base it on facts encountered in different places. And if you doubt it then ask why you can see plain JDBC URL in Hibernate configuration all over the place in businesses. Many simply dump the heavyweigtt idea of J2EE and go lightweight... also using plain connections based on DriverManager.
You want to get your career on line then go ahead with XA DataSources and recovery of failed transactions where poor XA implemetation failed badly.