pool wikipedia

Chapter 1 selection of thread pool and thread count, selection of Thread Pool Note: This chapter mainly refers to "large-scale distributed Java applications: basic and practice" and "large-scale website technical architecture: Core Principles and case analysis". 1. Two Selected angles High Performance: Submit the tasks submitted to the thread pool to the thread

There are many applications of threads and processes, mainly dealing with concurrency and multitasking. However, when there are too many threads and processes open, the overhead of the system can cause poor performance or even crash. At this point, you want a way to specify a policy that can only execute a specified number of threads and processes. In particular, there may be situations where there are too many threads or processes that you do not know how many threads or processes to open. As a

Introduction: The recent project with the integration of 360 project interface, there is a feedback interface (that is, we receive the request, need to respond immediately, and also have an interface to push to their other calculations), the push process time, or two interfaces can not be returned at the same time, there are sequencing. And then I thought about putting my controller back in a moment to accept success, adding a new thread to do other time-consuming operations (thread

var Generic_pool = require (' Generic-pool '); var pool = Generic_pool. Pool ({ name: ' MySQL ', max:10, Create:function (callback) { NB Sp var Client = require (' mysql '). CreateConnection ({ Host: ' 127.0.0.1 ', User: ' Root ', Password: ' 123456 ', NBSP;N Bsp database: ' Weibo_gs ' }); CA Llback (null,client); }, destroy:functi

Label:selecterrohandretdes leaseuserlogmysq var Generic_pool = require (' Generic-pool '); var pool = Generic_pool. Pool ({ name: ' MySQL ', max:10, Create:function (callback) { var Client = require (' mysql '). CreateConnection ({ Host: ' 127.0.0.1 ', nbsp ; User: ' Root ', Password: ' 123456 ', database: ' Weibo_gs ' });

Reprinted: 1. Problem DescriptionWebProgramIt was very fast at the beginning of Tomcat, but after a while it was found that the speed became very slow.Check log output and find exceptions as follows:Org. Apache. commons. DBCP. sqlnestedexception: cannot get a connection, pool exhausted, cause:Java. util. nosuchelementexception: timeout waiting for idle objectAt the same time, in the sqlserver event probe, it is found that each SQL statement is exec

concurrent worker threads" there is no place to set, know friends can give me a message, thank youSo now the problem is, the maximum number of concurrent connections affects the number of queues, so is there any progress affecting the number of queued settings? Yes: Queue LengthQueue LengthAssuming that the maximum number of connections is set to 100,1000 a concurrent connection request comes up, first 900 is returned directly to the customer "HTTP Error 503." The service is unavailable. "Then

Object pool technology can avoidProgramCreates and deletes a large number of objects in the lifecycle. If you know that the program requires a large number of objects of the same type and the object's life cycle is very short, you can create a pool for these objects for caching. The most difficult aspect of Object pool implementation is to record which objects

High-concurrency epoll + thread pool, epoll in the thread pool-ehyyngp-chinaunix blog High-concurrency epoll + thread pool, epoll in the thread pool 21:53:38 Category:Linux Epoll is a perfect solution for High-concurrency servers in Linux. Because it is triggered based on events, it is more than an order of m

The thread pool essence is a producer-consumer model that maintains some threads to perform tasks while adding some tasks from the main thread. Now we discard the source of some complex state judgment, write a thread pool. Public classPoolt {It is possible to delete tasks frequently, and the list queue efficiency is highPrivate FinalBlockingqueueNewLinkedblockingqueue(); Private FinalHashsetNewHashset(); Pr

Solaris zfs Replace the Root Pool Disk (Replace a Disk in the ZFS Root Pool) in some cases, due to insufficient space or hardware faults, we need to Replace the boot Disk. The redundancy pool (mirrored pool) is relatively simpler than the hard disk in an image pool. You only

This chapter describes the lifecycle of a thread pool. In the "Java multi-thread series-" basic articles "01 Basic Concepts", we have introduced five States of threads: new state, ready state, running state, and blocking state, death status. The thread pool also has five States. However, the thread pool is different from the thread

The most recent period of time. This year began to put.I maintain the site has been error database connection is not found, link, connection pool exhaustion problem. caused By:org.apache.commons.dbcp.SQLNestedException:Cannot get a connection, pool exhausted2017-07-26 15:42:20,516 ERROR [STDERR] at Org.apache.commons.dbcp.PoolingDataSource.getConnection ( poolingdatasource.java:103)2017-07-26 15:42:20,516 E

The libvirt Storage section is studied. A simple example is used for test and verification: Import lib1_conn = libvirt. open ('qemu: // system') # conn = libvirt. open ('qemu: // system ') xmldesc = ''' Output result: virttest1 Delete storage volumes and storage pools Import lib1_conn = libvirt. open ('qemu: // system') # conn = libvirt. open ('qemu: // system ') ''' Delete pool vol ''' storage _ pool