memcached��ʼ�

�� ߣ��֮ ��ʱ�䣺2011-04-15 | ��壺�� С��

[��]memcached��ݿ��ѹ��ʱ��˾��⻺�⡣��Щ��⣬��Щ��£��Щ��¼��д��ġ� memcached��ʲô�� webӦ��ݱ��RDBMS��(��mysql).��ݿ��ȡ��ݣ��ŷ��...

memcached��ݿ��ѹ��ʱ��˾��⻺�⡣��Щ��⣬��Щ��£��Щ��¼��д��ġ�

memcached��ʲô��
webӦ��ݱ��RDBMS��(��mysql).��ݿ��ȡ��ݣ��ŷ��󣬳��ݿ⸺��أ��Ӧ��⡣memcached��ǽ��ݻ��浽�ڴ��У��߶�д��ݵ��

memcached�к��ص㣿
��㣺��һ��ֲ�ʽ;�ڶ�, ��档

��ֲ�ʽ

memcached�Ƿֲ�ʽ�ڴ滺��ǲ��ͨ�ŵġ��֮��ķֲ�ʽȡ��ڿͻ��˵�ʵ�֡��ô��ν��⣬��̨memcached��ν�key=>value��͵��ݴ��ŵ�memcached��?

��֣� ��㷨��Բ��(�ٷ��,һ��㷨).
�ȿ��㷨.�Ƚ�memcached��1,2,3.��key��hashֵ��Ȼ��Է��3��õ��(��2)��ݷŵ�2�ϡ�
�˷��ŵ㷽��򵥣��ڷ�ɢ��ݡ��ǣ��һ̨memcached��key��hashֵ��Ե��ͱ��ˣ��Ʊ�Ҫ��ݣ��۲�С��ԣ��Բ��֮��
Բ�㷨�ǻ��Consistent Hashing��˼�롣�򵥵�˵��ȵó�memcached��Ĺ�ϣֵ��õ�һ��0-2��32�η��Բ�ϡ�Ȼ��ͬ��key�Ĺ�ϣֵ��ӳ�䵽��ͬ��Բ�ϡ��ӳ��λ�ÿ�ʼ˳ʱ��ң��ݱ��浽�ҵ��ĵ�һ��ϡ��µ�memcached��ʱ�򣬿��޶ȵļ��ټ��顣

php��Consistent Hashing��ʵ��
memcache�ͻ��˵�ʵ��:

    
            1
            ��php.ini������memcache.hash_strategy = consistent

memcached�ͻ��˵�ʵ��:

    
            1
            $mc = new Memcached(); 
        
            2
            $mc->setOption(Memcached::OPT_DISTRIBUTION,Memcached::DISTRIBUTION_CONSISTENT); 
        
            3
            $mc->setOption(Memcached::OPT_LIBKETAMA_COMPATIBLE, true);

php�ͻ��memcached vs memcache
��Ҳû��ס�memcached�ǻ��libmemcached�⣬�汾��memcacheҪ�£�֧�ָ��memcachedЭ�飬��Ӧ��memcache.

memcached�İ�װ

    
            1
            sudo apt-get install memcached 
        
            2
            yum install libevent lievent-devel memcached

��б��Ҳ�ɡ�

memcached��

memcached -d -m 1024 -l localhost -p 11711
-p ʹ�õ�tcp�˿�
-m ��ڴ�ʹ�á�Ĭ��64M
-d ��Ϊdaemon�ں�̨��

memcached��ݲ��

    
            1
            $mc = new memcached(); 
        
            2
            $key = 'test'; 
        
            3
            $mc->add($key,'okok');//�������� 
        
            4
            $mc->get($key);//��ȡ���� 
        
            5
            $mc->replace($key,'iii');//�滻���� 
        
            6
            $mc->delete($key);//ɾ������ 
        
            7
            $mc->increment('count',19);//ԭ�Ӳ��� 
        
            8
            ...

memcached��ɾ��LRU
�ڴ��ʱ��Ҳ�й��ڹ��ʱ��ɾ��أ� memcachedʹ��LRU(Least Recently Used).��ʹ�õļ�¼��ɾ��ԣ��ڴ治��ʱ��memcached�Ὣ��ʹ�õļ�¼�ռ��µļ�¼��-M��Խ��˹��ܡ��Ȼ��ʹ�á�

ԭ�ģ�http://www.cardii.net/memcached-note/

ת��ע��Դ��ITѧϰ�� ַ��http://www.t086.com/ ��Ƽ��
�ر�� վ��ر��ֹת�ص�ר��¿��ת�أ��ע��ԭʼ��ߡ��°�Ȩ��ԭʼ��С��ڱ��վת��µĸ��˺��վ��Ǳ�ʾ��л�⡣��վת�ص��а�Ȩ��ϵ��ǣ��ǻᾡ��Ը��

�� ( memcache memcached �� )

��Ӧ�Բ��(2) - ��ϲ��첽��

MySQL��ٲ�ѯ�ٶȵĶ��ѯ��

PHP Memcached ��Ӧ��

mysql memcached UDF ��װ��

��PHP��ʦ�Ŀ��ԭ��

Redis��7�ּ��Ӧ�ó��

Memcached��Ĺ�ʱ��Redis��Memcached�ıȽ�

�˽��Щ�֣��

memcached���ʼ�

memcached��ʼ�