connection-pooling

问题 I have a java client server which is supposed to establish connection pool on startup but its failing on timeout error. There are so many threads on this same issue but none of the solutions worked for me AM using jdk 7 and below is the mchange maven dependency <dependency> <groupId>com.mchange</groupId> <artifactId>c3p0</artifactId> <version>0.9.2.1</version> </dependency> jdbc.properties url=jdbc\:sqlserver\://server\\instance;databaseName\=db driver=com.microsoft.sqlserver.jdbc

问题 What I'm trying to do is to update my database after a period of time. So I'm using java scheduler and connection pooling. I don't know why but my code only working once. It will print: init success success javax.naming.NameNotFoundException: Name [comp/env] is not bound in this Context. Unable to find [comp]. at org.apache.naming.NamingContext.lookup(NamingContext.java:820) at org.apache.naming.NamingContext.lookup(NamingContext.java:168) at org.apache.naming.SelectorContext.lookup

问题 So I am new to connection pooling. I am trying to determine how to use a pool in order to speed up my query. I have a query that works, but I dont think I am using the pool correct. Here is the syntax, if you see anywhere I could be more efficient please let me know. try: db=mysql.connector.connect(poolname="mypool", pool_size=10, **config) cursor.execute(query1) df1=create_df(cursor) cursor.execute(query2) df2=create_df(cursor) cursor.execute(query3) df3=create_df(cursor) 回答1: Your question

问题 So I am new to connection pooling. I am trying to determine how to use a pool in order to speed up my query. I have a query that works, but I dont think I am using the pool correct. Here is the syntax, if you see anywhere I could be more efficient please let me know. try: db=mysql.connector.connect(poolname="mypool", pool_size=10, **config) cursor.execute(query1) df1=create_df(cursor) cursor.execute(query2) df2=create_df(cursor) cursor.execute(query3) df3=create_df(cursor) 回答1: Your question

问题 I'm developing simple Spring Boot web application with embedded Jetty server. I'd like to have some statistics on connection pool usage (i.e. how many threads, avg request time. avg queue wait time, queue size etc.) I realized that Spring Boot configures Jetty with QueuedThreadPool which has few basic metrics. Is there more sophisticated bean or module designated for statistics collecting in Spring Boot? How to enable it? 回答1: Have you had a look at Spring boot actuator? It provides you with

问题 In order to optimize the connection pool size, I thought it would make sense to graph query queue times. Is it possible to retrieve this metric from Mongoose? 回答1: See here for node monitoring. You need cmap events that apparently aren't documented there, see Ruby docs for example but they should be published by the node driver also. Track ConnectionCheckOutStarted and ConnectionCheckOutSucceeded and subtract the times to get the wait time. 来源： https://stackoverflow.com/questions/63652084

问题 In order to optimize the connection pool size, I thought it would make sense to graph query queue times. Is it possible to retrieve this metric from Mongoose? 回答1: See here for node monitoring. You need cmap events that apparently aren't documented there, see Ruby docs for example but they should be published by the node driver also. Track ConnectionCheckOutStarted and ConnectionCheckOutSucceeded and subtract the times to get the wait time. 来源： https://stackoverflow.com/questions/63652084

问题 From the c3p0 documentation: For some applications, high performance is more important than the risk of an occasional database exception. In its default configuration, c3p0 does no Connection testing at all. Setting a fairly long idleConnectionTestPeriod , and not testing on checkout and check-in at all is an excellent, high-performance approach. If I understand the meaning of the c3p0 configuration properties correctly, if the database becomes unavailable for a short period of time and then

问题 I am actually reading Oracle-cx_Oracle tutorial. There I came across non-pooled connections and DRCP, Basically I am not a DBA so I searched with google but couldn't found any thing. So could somebody help me understand what are they and how they are different to each other. Thank you. 回答1: Web tier and mid-tier applications typically have many threads of execution, which take turns using RDBMS resources. Currently, multi-threaded applications can share connections to the database efficiently

问题 In order to secure our database we create a schema for each new customer. We then create a user for this schema and when a customer logs in via the web we use their user and hence prevent them gaining access to other areas of the database. Our issue is with connection pooling as it is a bit inefficient to keep creating/dropping new connections for these users. We would like to have a solution that can work across many hundreds of different database users. We've looked at pg_bouncer, but the