使用客户端工具连接pg,连接失败,报错以下错误: FATAL: remaining connection slots are reserved for non-replication superuser connections 查看数据库连接状态和配置信息 select * from pg_stat_activity where pid<>pg_backend_pid() and state='idle';##pg_backend_pid()的结果是当前会话的pid select datnam…

http://docs.oracle.com/cd/E13222_01/wls/docs81/ConsoleHelp/jdbc_connection_pools.html#1106016 JDBC Connection Pools [Attributes and Console Screen Reference for JDBC Connection Pools] The following sections explain how to configure and manage JDBC co…

Android系统--输入系统(十六)APP跟输入系统建立联系_InputChannel和Connection 0. 核心:socketpair机制 1. 回顾Dispatch处理过程: 1.1 放入队列前稍加处理 分类:Global Key/System Key/User Key 处理紧急事件(比如来电的时候按下音量键静音) 1.2 InputReader线程将读到的输入事件稍加处理后放入mInboundQueue队列中,接着唤醒Dispatch线程 1.3 Dispatch从mInbound…

最近使用HttpClient 4.5 使用 CloseableHttpClient 发起连接后,使用CloseableHttpResponse 接受返回结果,结果就报错了,上网查了下,有位stackoverflow的大兄弟说,只要将: CloseableHttpClient httpClient = HttpClients.createDefault(); 改为: CloseableHttpClient httpClient = HttpClients.custom().setConnectio…

SQL Server Connection Pooling (ADO.NET) Connecting to a database server typically consists of several time-consuming steps. A physical channel such as a socket or a named pipe must be established, the initial handshake with the server must occur, the…

ConnMan    Connection Manager简称connman,connman是使用d-bus做为进程间通信机制来管理Linux网络链接的一种软件.在connman的d-bus接口中,有一个接口叫做service.该接口的全称为:net.connman.Service,自然是挂在net.connman上面的.做为net.connman.Service接口,它可以访问到network的细节以及用户偏好使用什么类型的网络(比如3g.wifi.wimax等等).外部的程序就通过net.c…

在connection的生命里,会一直有一个user thread(以及user thread对应的THD)陪伴它. Connection和Session概念 来自Stackoverflow的一个回答: A session is just a result of a successful connection. Any MySQL client requires some connection settings to establish a connection, and after the c…

http://www.onjava.com/pub/a/onjava/2001/05/30/optimization.htmlComparing the performance of LinkedLists and ArrayLists (and Vectors) (Page last updated May 2001, Added 2001-06-18, Author Jack Shirazi, Publisher OnJava). Tips: ArrayList is faster than…

SQLSERVER性能计数器的简单剖析 今晚看了这篇文章:SQL Server 2012新performance counter:非常实用的Batch Resp Statistics 文章里介绍到SQLSERVER2012新的性能计数器“Batch Resp Statistics” 其实我有一个问题:当我的电脑里有多个版本的SQLSERVER或者多个SQLSERVER实例,SQLSERVER是怎麽区分不同版本的不同计数器的呢? 比如下面SQL脚本,在SQL2012里执行可以看到新的性能计数器Ba…

/* 输入文件见337.in.txt 输出文件见338.out.txt */ #include <iostream> #include <cctype> #include <fstream> #include <cstring> using namespace std; * + ; //单词表的最大值 + ; //单词长度的最大值 struct WordList { char word[maxWord]; //单词 int fre; //词频 } list[…