Cassandra(一):逼上梁山
«IM场景下的系统拓扑及协议优化»中留下一个问题:存储交互的每条协议,按大小排序给出Top N ?
首先这个问题其实有两层含义:
- 如何存 ? (除了高效的写,还要有足够的容量)
- 排序给出Top N ? (即使样本再大,也要排序给出结果)
最简单的办法:mysql中创建一张表,order by bytes desc limit N.这是所有程序员都能想到的短平快的办法,然并卵.有人说,用Hadoop吧.可目前的需求用Hadoop解决有些小题大作,最后锁定Nosql领域的Cassandra.就像这名字一样,清澈而又明亮.逼上梁山…
cassandra:“你也是，疯狂也将找上你。”
The Apache Cassandra database is the right choice when you need scalability and high availability without compromising performance. Linear scalability and proven fault-tolerance on commodity hardware or cloud infrastructure make it the perfect platform for mission-critical data. Cassandra’s support for replicating across multiple datacenters is best-in-class, providing lower latency for your users and the peace of mind of knowing that you can survive regional outages.
眼前一亮
分布式 线性扩展
package com.atschx.cassandra.sample;
import java.net.InetAddress;
import java.util.Date;
import java.util.UUID;
public class IMProtocolStatisticModel {
private UUID id;
private Integer uid;
private Long sid;
private InetAddress ipAddress;
private Date occuredOn;
private Integer seq;
private Integer channel;
private Integer tag;
private Integer type;
private String packet;
private Integer bytes;
private String clientVersion;
private Integer clientType;
....//省略setter和getter
}