Python Operation Memcache

Memcached is a high-performance distributed memory object caching system for dynamic Web applications to mitigate database load. It improves the speed of dynamic, database-driven Web sites by caching data and objects in memory to reduce the number of times a database is read. Memcached is based on a hash map that stores key/value. Its daemon (daemon) is written in C, but the client can write in any language and communicate with the daemon through the memcached protocol.

Installation

Cd/usr/local/src

wget http://memcached.org/latest

TAR-ZXVF memcached-1.x.x.tar.gz

CD memcached-1.x.x

./configure && make && make test && make install

Start

Memcached-d-M 10-u root-l 127.0.0.1-p 12000-c 256-p/export/servers/memcache/logs/memcache.pid

-P Specify port number (default 11211)

-m specifies the maximum amount of memory to use (default 64MB)

-T thread count (default 4)

-L connected IP address, default is native

-D starts with the daemon process

-c Maximum number of simultaneous connections, default is 1024

-P Develop memecache PID file

-H Printing Help information

PS-EF Check if Memcache is started, check port number

Python Operation Memcache Cluster

The PYTHON-MEMCACHD module natively supports cluster operations by maintaining a list of hosts in memory, and the weight values of the hosts in the cluster are proportional to the number of occurrences of the host in the list.

Host weights

1.1.1.1 1

1.1.1.2 2

1.1.1.3 1

Then in memory the host list is: host_list=[' 1.1.1.1 ', ' 1.1.1.2 ', ' 1.1.1.2 ', ' 1.1.1.3 ',]

Example:

MC = Memcache. Client ([' 1.1.1.1:12000 ', 1), (' 1.1.1.2:12000 ', 2), (' 1.1.1.3:12000 ', 1)], debug=true)

Mc.set (' K1 ', ' v1 ')

If the user wants to create a key-value pair in memory (for example: K1 = "V1"), perform the following steps:

The K1 is converted into a number according to the algorithm;

The number and host list length are calculated as remainder, and a value of n (0 <= N < list length) is obtained;

In the host list, the value obtained from the 2nd step is the index to get the host, for example: Host_list[n];

The connection will be taken in the 3rd step of the host, placing K1 = ' V1 ' in the server's memory.

In the above example, we call the Memcache module to achieve access to the memcached data, debug=true indicates that there is an error in the run, the error message is displayed, after the line to remove the parameter.

Python Operation Memcache