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multiple Threads read to the same table in database by using the same connection in java?

I have defined three transaction in which select operations and SELECT operations are happening on the different parameter passed . I try to invoke this method concurrently . I am get an error:
o.h.engine.jdbc.spi.SqlExceptionHelper : SQL Error: 0, SQLState: null
Aug 25, 2020 # 12:16:39.000 2020-08-25 06:46:39.388 ERROR 1 --- [o-9003-exec-630] o.h.engine.jdbc.spi.SqlExceptionHelper : Hikari - Connection is not available, request timed out after 60000ms.
And sometimes
org.postgresql.util.PSQLException: FATAL: remaining connection slots are reserved for non-replication superuser connections
I am new to java. Please guide me to solve this issue. Do I need to write multithreading to access number of resources or configuration issue?
hikari:
poolName: Hikari
autoCommit: false
minimumIdle: 5
connectionTimeout: 60000
maximumPoolSize: 80
idleTimeout: 60000
maxLifetime: 240000
leakDetectionThreshold: 300000

Multiple Threads read to the same table in database by using the same connection in java?
This is generally speaking not going to work. The JDBC API types Connection, Statement, ResultSet and so on are not generally thread-safe1. You should not try to use on instance in multiple threads.
If you want to avoid having multiple connections open the normal approach is to use a JDBC connection pool to manage the connections. When a thread needs to talk to the database, it gets a connection from the pool. When it has finished talking to the database, it releases it back to the pool.
In the PostgreSQL / Hikari case:
For PostgreSQL - "Using the driver in a multi-threaded or a servlet environment"
For Hikari - the getConnection() call is thread-safe, but I couldn't find anything that explicitly talked about the thread-safety of the connection object when shared by multiple threads.
1 - I have seen it stated that a spec compliant JDBC driver should be thread-safe, but I could not see where the JDBC spec actually requires this to be so. But even assuming that it does say that somewhere, the threads sharing a connection would need to coordinate very carefully to avoid things like one thread causing another thread's resultset to "spontaneously" close.

Connection Pooling is not working for DB2 database through UCP

We are writing a simple standalone java batch. We are using DB2 database. We are trying to do connection pooling using UCP (Version: ucp-11.2.0.3.0).
We have initialized minimum pool size as 5. But when we retrieve one connection and when we are printing the Available and Borrowed connections, we are getting Available as 0 and Borrowed as 1. When retrieving multiple connections, it is still printing the same eventhough the mimimum pool size is 5. we are not getting the any exception eventhough the max limit is crossed. Could you please help us on resolving the issue?
PoolDataSource pds = PoolDataSourceFactory.getPoolDataSource();
pds.setConnectionFactoryClassName("XXXX");
pds.setURL("XXX");
pds.setUser("CCCC");
pds.setPassword("xxx");
pds.setInitialPoolSize(1);
pds.setMinPoolSize(5);
pds.setMaxPoolSize(10);
connection = pds.getConnection();
System.out.println("\nConnection borrowed from the pool");
int avlConnCount = pds.getAvailableConnectionsCount();
System.out.println("\nAvailable connections: " + avlConnCount);
int brwConnCount = pds.getBorrowedConnectionsCount();
System.out.println("\nBorrowed connections: " + brwConnCount);
Output:
-------
Connection borrowed from the pool
Available connections: 0
Borrowed connections: 1
Connection borrowed from the pool
Available connections: 0
Borrowed connections: 1

UCP is the connection pooling library for Oracle Database.
Db2 does not come with its own connection pooling library, instead, it works well with major connection pooling libraries, including Apache DBCP and HikariCP.

Infinispan TimeoutException ISPN000476

I am experiencing Embedded InfiniSpan cache issue where nodes timeout on re-joining the cluster.
Caused by: org.infinispan.util.concurrent.TimeoutException: ISPN000476: Timed out waiting for responses for request 7 from vvshost
at org.infinispan.remoting.transport.impl.SingleTargetRequest.onTimeout(SingleTargetRequest.java:64)
at org.infinispan.remoting.transport.AbstractRequest.call(AbstractRequest.java:86)
at org.infinispan.remoting.transport.AbstractRequest.call(AbstractRequest.java:21)
The only way I can get the node to re-join is to switch off the cache and delete all local cache persistence files.
Here is the configuration which I am using:
Transport:
TransportConfigurationBuilder - defaultClusteredBuild
JMX Statistics - Enabled
Duplicate domains - Allowed
Cache Manager:
Manager Class - EmbeddedCacheManager
Memory - Memory Size: 0
Persistence: Single File Store
async: disabled
Clustering Cache Mode - CacheMode.DIST_SYNC

It seems right to me, but the value of remote-timeout is "15000" milliseconds by default. Increase the timeout until you stop getting the error.
Hope it helps

Websphere HTTP outbound connection pool usage

I have an application running on Websphere Application Server 6.1.0.43. And I'm having slowdown issues when thrying to invoke a remote service.
The slowdown is on the method findGroupAndGetConnection from the class outboundConnectionCache.
According to the IBM APAR PK94494:
The delay occurs after the client-side JAX-RPC handler (if present) is invoked and before the actual SOAP message is sent to the provider.
Because the delay occurs in the IBM web services engine, this problem
can be difficult to detect.
A com.ibm.ws.webservices.engine.transport.*=all trace will show entries similar to these which repeat:
[8/19/09 18:08:29:658 GMT] 00000047 OutboundConne 1 Enter:
WSWS3595I: Current pool size: 25. Connections-in-use size: 0.
Configured pool size: 25
In addition, that same trace spec will show long delays in executing
the .findGroupAndGetConnection() method:
[8/19/09 18:08:03:428 GMT] 00000047 OutboundConne >
OutboundConnectionCache.findGroupAndGetConnection()
WAITING_THREADS_THRESHOLD is 5 Entry
[8/19/09 18:08:38:358 GMT] 00000047 OutboundConne <
OutboundConnectionCache.findGroupAndGetConnection() Exit
And they recommend the following:
Reduce the 'com.ibm.websphere.webservices.http.connectionPoolCleanUpTime' from
the default of 180 to 120 seconds
Increase the max connections 'com.ibm.websphere.webservices.http.maxConnection' property from
default of 25 to 50. This will also require increasing the web
container thread pool size to 100.
Before changing the default properties I decided to monitor the Web Container thread usage and I noticed that maximum thread pool size (50) is never reached, but the minimum pool size (10) is reached very often, forcing connections to be destroyed and recreated.
Running over the minimum pool size will cause this slowdown? Should I increase the minimum pool size? Is my problem something other than http outbound connection pool?

Unable to get resource from jedis

After running my application, i am getting this error after around 5 mins.
Even though i am returning the resource after use, i keep getting this.
I have built jedis-2.2.2-SNAPSHOT.jar from the jedis code base, since its not released yet
I had set the minIdle = 100, maxIdle=200 & maxActive=200. At the time of this exception, the connection count to redis was 122 from my application
redis.clients.jedis.exceptions.JedisConnectionException: Could not get a resource from the pool
at redis.clients.util.Pool.getResource(Pool.java:42)
Caused by: java.util.NoSuchElementException: Timeout waiting for idle object
at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:442)
at org.apache.commons.pool2.impl.GenericObjectPool.borrowObject(GenericObjectPool.java:360)
at redis.clients.util.Pool.getResource(Pool.java:40)
... 6 more

Did you check that redis is still up & running ?
If not, investigate why it died.
try a redis-cli in a terminal if you can. "info" would give you more details.