<?xml version="1.0" encoding="utf-8" ?><rss version="2.0"><channel><title><![CDATA[robin622的专栏]]></title><description><![CDATA[]]></description><link>https://blog.youkuaiyun.com/robin622</link><language>zh-cn</language><generator>https://blog.youkuaiyun.com/</generator><copyright><![CDATA[Copyright &copy; robin622]]></copyright><item><title><![CDATA[动态hash方法]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/50672544</link><guid>https://blog.youkuaiyun.com/robin622/article/details/50672544</guid><author>robin622</author><pubDate>Tue, 16 Feb 2016 08:01:46 +0800</pubDate><description><![CDATA[动态hash方法之一

 

本文将介绍三种动态hash方法。

散列是一个非常有用的、非常基础的数据结构，在数据的查找方面尤其重要，应用的非常广泛。然而，任何事物都有两面性，散列也存在缺点，即数据的局部集中性会使散列的性能急剧下降，且越集中，性能越低。

数据集中，即搜索键在通过hash函数运算后，得到同一个结果，指向同一个桶，这时便产生了数据冲突。

通常解决数据冲突的方法]]></description><category></category></item><item><title><![CDATA[Hash 一致性算法]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/50672540</link><guid>https://blog.youkuaiyun.com/robin622/article/details/50672540</guid><author>robin622</author><pubDate>Tue, 16 Feb 2016 07:19:31 +0800</pubDate><description><![CDATA[应用在 数据库分库 等领域:

如果我们采用取余 或者 普通hash的话.

再一次增加一台机器的过程中, 会导致大面积数据迁移问题.要不然就会出现入库不平均.

consistent hashing 就是为了解决这个问题的.

初始分配:









将所有机器通过hash算法分布在一个2^32次方的一个圆环上.

当每一次入库的时候.都会根据has]]></description><category></category></item><item><title><![CDATA[hadoop- cluster setup]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/25951835</link><guid>https://blog.youkuaiyun.com/robin622/article/details/25951835</guid><author>robin622</author><pubDate>Fri, 16 May 2014 10:04:04 +0800</pubDate><description><![CDATA[1, single node setup
2, 
Setup passphraseless ssh

Now check that you can ssh to the localhost without a passphrase:
$ ssh localhost 
If you cannot ssh to localhost without a passphrase, execute]]></description><category></category></item><item><title><![CDATA[big-data 3: presudo distributed configuration]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/25948049</link><guid>https://blog.youkuaiyun.com/robin622/article/details/25948049</guid><author>robin622</author><pubDate>Fri, 16 May 2014 08:27:53 +0800</pubDate><description><![CDATA[1, same as before,but need to change

Configuration

Use the following: 

conf/core-site.xml:

     
         fs.default.name
         hdfs://localhost:9000
     



conf/hdfs-site.xml:

   ]]></description><category></category></item><item><title><![CDATA[Big Data 2-- 单机配置hadoop]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/25943249</link><guid>https://blog.youkuaiyun.com/robin622/article/details/25943249</guid><author>robin622</author><pubDate>Fri, 16 May 2014 07:57:24 +0800</pubDate><description><![CDATA[1, 找到一个想要安装的hadoop版本,]]></description><category></category></item><item><title><![CDATA[Big Data--1, 初识hadoop]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/25941613</link><guid>https://blog.youkuaiyun.com/robin622/article/details/25941613</guid><author>robin622</author><pubDate>Fri, 16 May 2014 05:38:07 +0800</pubDate><description><![CDATA[1， 什么是hadoop?
Apache 开源的]]></description><category></category></item><item><title><![CDATA[good blog]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/5376133</link><guid>https://blog.youkuaiyun.com/robin622/article/details/5376133</guid><author>robin622</author><pubDate>Sat, 13 Mar 2010 10:53:00 +0800</pubDate><description><![CDATA[fancyhf(about architecture)http://blog.youkuaiyun.com/fancyhf/archive/2009/03/18/4002609.aspx]]></description><category></category></item><item><title><![CDATA[mysql的日期和时间函数]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2312854</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2312854</guid><author>robin622</author><pubDate>Mon, 21 Apr 2008 18:25:00 +0800</pubDate><description><![CDATA[ mysql的日期和时间函数2006-11-09 15:06:52 这里是一个使用日期函数的例子。下面的查询选择所有 date_col 值在最后 30 天内的记录。 mysql> SELECT something FROM tbl_name           WHERE TO_DAYS(NOW()) - TO_DAYS(date_col) <= 30;DAYO]]></description><category></category></item><item><title><![CDATA[lm]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2249767</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2249767</guid><author>robin622</author><pubDate>Fri, 04 Apr 2008 13:50:00 +0800</pubDate><description><![CDATA[ http://blog.youkuaiyun.com/taikongzhu1980/archive/2005/03/27/331759.aspx]]></description><category></category></item><item><title><![CDATA[cdn]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2233738</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2233738</guid><author>robin622</author><pubDate>Mon, 31 Mar 2008 18:04:00 +0800</pubDate><description><![CDATA[http://www.jojin.com/net/guanyu.htm ]]></description><category></category></item><item><title><![CDATA[免费的Javascript日期输入及选择控件大杂烩！]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2232518</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2232518</guid><author>robin622</author><pubDate>Mon, 31 Mar 2008 11:43:00 +0800</pubDate><description><![CDATA[http://joesen.f2blog.com/index.php?load=read&id=27 ]]></description><category></category></item><item><title><![CDATA[什么用Utf-8编码?]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2229262</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2229262</guid><author>robin622</author><pubDate>Sat, 29 Mar 2008 21:32:00 +0800</pubDate><description><![CDATA[Utf-8编码在国外应用普遍，为什么在国内应用却不多呢？尤其各大门户网站采用Utf-8的几乎没有。是否采用Utf-8，这个问题大家争论已久，但是很少有人系统地解说为什么要采用Utf-8编码？凡事皆有正反！采用Utf-8编码同样有其利弊，当利大于弊，我们当然就采用Utf-8？关于UTF-8编码和中文字符集中文有三种字符集，统一文字的编码将是进一步交流的基础。·国内网站和BLOG较多使用简体中文编码G]]></description><category></category></item><item><title><![CDATA[css]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2218644</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2218644</guid><author>robin622</author><pubDate>Wed, 26 Mar 2008 09:32:00 +0800</pubDate><description><![CDATA[供应默勒接触器FAZ-B10/1FAZ-B13/2FAZ-B16/1FAZ-B16/2FAZ-B6/1FAZ-C0,5/1FAZ-C1/1FAZ-C10/1FAZ-C10/2FAZ-C10/3FAZ-C16/1FAZ-C16/2FAZ-C16/3FAZ-C2/1FAZ-C20/1FAZ-C25/1FAZ-C3/1FAZ-C32/1FAZ-C4/1FAZ-C40/3FAZ-C6/1FAZ-D10]]></description><category></category></item><item><title><![CDATA[code]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2198411</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2198411</guid><author>robin622</author><pubDate>Wed, 19 Mar 2008 22:42:00 +0800</pubDate><description><![CDATA[jsp:::package com.zw.fantasticblog.util;import java.awt.*;import java.awt.image.BufferedImage;import java.io.IOException;import java.io.OutputStream;import java.util.*;import javax.servlet.Servlet]]></description><category></category></item><item><title><![CDATA[aja]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2195816</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2195816</guid><author>robin622</author><pubDate>Wed, 19 Mar 2008 07:32:00 +0800</pubDate><description><![CDATA[js代码：var xmlHttp=null;function createXMLHttpRequest(){ if(window.ActiveXObject) {  xmlHttp=new ActiveXObject("Microsoft.XMLHTTP"); } else if(window.XMLHttpRequest) {  xmlHttp=new XMLHttpRequest(); }]]></description><category></category></item><item><title><![CDATA[虚拟域名的配置和设计方法]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2156837</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2156837</guid><author>robin622</author><pubDate>Fri, 07 Mar 2008 15:46:00 +0800</pubDate><description><![CDATA[虚拟域名的配置和设计方法——http://www.weste.net作者：icech 第 1 页 共 12 页 2002-5-24目 录1、什么是域名？...........................................................................................................12、Internet上有哪些域名]]></description><category></category></item><item><title><![CDATA[it咨询]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2156813</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2156813</guid><author>robin622</author><pubDate>Fri, 07 Mar 2008 15:37:00 +0800</pubDate><description><![CDATA[http://www.itlaw.com.cn/html/falvxuetang/list_5_3.html ]]></description><category></category></item><item><title><![CDATA[虚拟主机相关知识  ]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2156453</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2156453</guid><author>robin622</author><pubDate>Fri, 07 Mar 2008 13:48:00 +0800</pubDate><description><![CDATA[                        虚拟主机相关知识                                                                                                                                                ]]></description><category></category></item><item><title><![CDATA[如何防止IE缓存jsp文件  ]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2156094</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2156094</guid><author>robin622</author><pubDate>Fri, 07 Mar 2008 11:44:00 +0800</pubDate><description><![CDATA[1, 使用java提供的方法，在jsp或者servlet中都可以 response.setHeader("Pragma","No-cache"); response.setHeader("Cache-Control","no-cache"); response.setDateHeader("Expires", 0); %> 2, 使用HTML标记，如下：      ]]></description><category></category></item><item><title><![CDATA[MyEclipse+Resin3.1.x 实现Web工程自动部署      ]]></title><link>https://blog.youkuaiyun.com/robin622/article/details/2156093</link><guid>https://blog.youkuaiyun.com/robin622/article/details/2156093</guid><author>robin622</author><pubDate>Fri, 07 Mar 2008 11:42:00 +0800</pubDate><description><![CDATA[在MyEclipse中发布项目时,会将项目发布到resin安装目录的deploy目录下,但是访问时会出现HTTP404错误resin3.0中，deploy是默认的发布目录，在MyEclipse中直接发布到resin的deploy目录中，起动服务器就会运行发布的项目，而在resin-3.1.x中发布到deploy目录下的项目不会运行，需要修改conf目录下的resin.conf文件有两种]]></description><category></category></item></channel></rss>