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wget http://repos.fedorapeople.org/repos/dchen/apache-maven/epel-apache-maven.repo -O /etc/yum.repos.d/epel-apache-maven.repo
yum install apache-maven

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目的

• 了解JAVA程序性能调优的过程、原理以及常见方法；在这方面做到“知道自己不知道”；
• 不用了解太多细节，这些细节的学习需要结合大量实践，只能有机会再深入。

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TODO/疑问

• 为什么优化GC时，要按照“确定内存需求" -> "延迟调优" -> "吞吐量调优"的顺序？ 是因为这些指标之间存在该顺序表明的依赖关系？
• 如何定义性能需求？

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import com.fasterxml.jackson.annotation.JsonPropertyOrder;
import com.fasterxml.jackson.databind.ObjectWriter;
import com.fasterxml.jackson.dataformat.csv.CsvMapper;
import com.fasterxml.jackson.dataformat.csv.CsvSchema;
import java.io.BufferedOutputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;

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#! /bin/sh
#
# chkconfig: - 55 45
# description:  The memcached daemon is a network memory cache service.
# processname: memcached
# config: /etc/sysconfig/memcached
# pidfile: /var/run/memcached/memcached.pid

# Standard LSB functions
#. /lib/lsb/init-functions

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var CryptoJS = require('crypto-js')
var request = require('request-promise')

/*
 * npm install crypto-js request-promise request
 * node wx_t1t_hack.js
 */

// export function testEncription(msg, fullKey) {
//   var fullKey = fullKey.slice(0, 16)

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The introduction to Reactive Programming you've been missing

(by @andrestaltz)

---

This tutorial as a series of videos

If you prefer to watch video tutorials with live-coding, then check out this series I recorded with the same contents as in this article: Egghead.io - Introduction to Reactive Programming.

---

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/* TOP SLOW REQUESTS */
/* time is in microseconds */
SELECT  creation_time 
        ,last_execution_time
        ,total_physical_reads
        ,total_logical_reads 
        ,total_logical_writes
        , execution_count
        , total_worker_time
        , total_elapsed_time

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http://rusanu.com/2014/02/24/how-to-analyse-sql-server-performance/

White Papers:
Waits and Queues White-Paper (2005) http://technet.microsoft.com/en-us/library/cc966413.aspx
Waits and Queues after 2005 - http://msdn.microsoft.com/en-us/library/ms179984.aspx

sys.dm_exec_requests	What is executing right now
sys.dm_os_waiting_tasks	Currently waiting tasks
sys.dm_os_wait_stats	Aggregated statistics about all wait types
sys.dm_exec_query_stats	runtime execution statistics for most queries

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git config merge.renormalize true # prevents unnecessary merge conflicts, http://stackoverflow.com/a/12194759/23566

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--from http://sqlblog.com/blogs/john_paul_cook/archive/2009/08/24/using-the-processes-query-outside-of-activity-monitor.aspx
/* ACTIVITY MONITOR */

 

/* Processes */

SELECT

   [Session ID]    = s.session_id,