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 private static class RemotingInvocationTimeoutScan implements Runnable {

        public void run() {
            while (true) {
                try {
                    for (DefaultFuture future : FUTURES.values()) {
                        if (future == null || future.isDone()) {
                            continue;
                        }
                        if (System.currentTimeMillis() - future.getStartTimestamp() > future.getTimeout()) {

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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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    /** Number of CPUS, to place bound on table size */
    static final int NCPU = Runtime.getRuntime().availableProcessors();

    /**
     * Table of cells. When non-null, size is a power of 2.
     */
    transient volatile Cell[] cells;

    /**
     * Base value, used mainly when there is no contention, but also as

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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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package com.air.jmh;

import java.sql.Timestamp;
import java.util.Date;
import java.util.Locale;
import java.util.TimeZone;
import java.util.concurrent.Executors;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

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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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git config --global alias.oa '!zsh -c '\''diff --old-line-format='' --new-line-format='' <(git rev-list --first-parent "${1:-master}") <(git rev-list --first-parent "${2:-HEAD}") | head -1'
git config --global alias.branchdiff '!sh -c "git diff `git oa`.."'
git config --global alias.branchlog '!sh -c "git log `git oa`.."'

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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。

---

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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acquire lock on object state
while (precondition does not hold) {
  release lock
  wait until precondition might hold
  optional fail if interrupted or timeout expires
  require lock
}
perform action
    release lock

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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