Ubuntu memcached Installation and configuration

 ubuntu memcached Installation and Configuration

It is divided into two processes: Memcache server-side installation and memcached client installation.

The so-called server-side installation is to install Memcache on the server (generally Linux system) to implement data storage

The so-called client installation refers to PHP (or other programs, memcache and other good API interface) to use the server-side memcache provided functions, PHP needs to add extensions.

1) Install Memcache server

sudo apt-get install memcached

After installing the Memcache server, we need to start the service:

memcached-d-M 128-p 11111-u root

Here you need to explain the startup parameters of the Memcached service:

-P Listening Port

-L connected IP address, default is native

-D Start memcached service

-D Restart Restart memcached service

-D Stop|shutdown Close the running memcached service

-D Install memcached service

-d Uninstall Uninstall memcached service

-U Run as (only valid when running as root)

-m maximum memory usage, in megabytes. Default 64MB

-M running out of memory and returning an error instead of deleting an item
-c Maximum number of simultaneous connections, default is 1024

-F Block size growth factor, default is 1.25-n minimum allocation space, key+value+flags default is 48
-H Display Help

2) Installing the Memcache client (PHP5 as an example)

sudo apt-get install Php5-memcache

After installation we need to make a simple configuration in php.ini, open the/etc/php5/apache2/php.ini file at the end to add the following:

[Memcache]

; Whether to transparently fail over to the other server when an error is encountered.

Memcache.allow_failover = On

; The maximum number of servers to try when accepting and sending data, only valid when Memcache.allow_failover is turned on. Memcache.max_failover_attempts = 20

The data will be transferred according to the block size set by this value. The smaller this value is, the more additional network traffic is required.

; If you find that unexplained speed decreases, you can try to increase this value to 32768.

Memcache.chunk_size = 8192

; The default TCP port to use when connecting to the memcached server.

Memcache.default_port = 11111

; Controls the policy that maps the key to the server. The default value of "standard" means using the previous version of the old hash policy.

; Set to "consistent" to allow the server to be added/removed from the connection pool without recalculating the mapping between key and server.

; memcache.hash_strategy = "standard"; Controls the hash function that maps the key to the server. The default value Crc32″ uses the CRC32 algorithm, while "FNV" indicates the use of the FNV-1A algorithm.

; The fnv-1a is slightly lower than the CRC32, but the hash effect is better.

; memcache.hash_function = "Crc32″

finally , save php.ini, perform sudo/etc/init.d/apache2 restart restart Apache.

3) using Memcache in PHP

<?php

$mem = new Memcache; Create a Memcache object

$mem->connect ("127.0.0.1″, 11111); Connecting Memcache servers

$val = "This is a memcache test.";

$key = MD5 ($val);

$mem->set ($key, $val, 0, 120); Add a cache with a cache time of 120s

if ($k = $mem->get (' key ')) {//To determine whether to get to the specified key

Echo ' Fromcache: '. $k;

} else {

echo ' normal '; Here we need to replace the query database and create the cache in actual use.

}

?>

so far, through the above steps, we have completed the configuration and basic use of memcache ...

4) methods provided by the Php5-memcache extension

Memcache::add-adds a value that returns false if it already exists
memcache::addserver-Add a server address that is available for use
memcache::close-Close a Memcache object
memcache::connect-Creating a Memcache Object
memcache_debug-Control Debugging function
Memcache::d ecrement-to subtract a value from a saved key
Memcache::d elete-Delete a key value
memcache::flush-to clear all cached data
memcache::get-get a key value
memcache::getextendedstats-get run System statistics for all processes in the process pool
memcache::getserverstatus-getting parameters to run the server
memcache::getstats-returns some running statistics for the server
memcache::getversion-returns the version information of the running Memcache
memcache::increment-an addition to the value in a saved key
Memcache: Create a Memcache Persistent connection object:p connect-
Memcache::replace-r Overwrite an existing key
Memcache::set-adds a value that, if already present, overwrite
memcache::setcompressthreshold-compression of data larger than a certain size
memcache::setserverparams-modifying the server's parameters at run time

The following are the installation and use of memcached on the operating system Ubuntu 10.04:

1. Download unzip, install Libevent

mkdir ~/SRC

CD ~/SRC

Wgethttp://www.monkey.org/~provos/libevent-2.0.10-stable.tar.gz

Tar xzvf libevent-2.0.10-stable.tar.gz

CD libevent-2.0.10-stable

./configure--prefix=/usr

Make

sudo make install

Cd..

2. Test whether the Libevent is installed successfully:

# Ls-al/usr/lib | grep libevent

3. Download unzip, install memcached

Wgethttp://memcached.googlecode.com/files/memcached-1.4.5.tar.gz

Tar xzvf memcached-1.4.5.tar.gz

CD memcached-1.4.5

./configure--with-libevent=/usr

Make

sudo make install

Cd..

4. Test whether the memcached is installed successfully:

# ls-al/usr/local/bin/mem*

5. Start the server side of the memcache:

#/usr/local/bin/memcached-d-M 10-u root-l127.0.0.1-p 11211-c 256-p/tmp/memcached.pid

The-D option is to start a daemon,

-M is the amount of memory allocated to Memcache, in megabytes, I'm 10MB,

-U is the user running memcache, I am root here,

-L is the server IP address of the listener, if there are multiple addresses, I specify the server IP address 127.0.0.1,

-P is the port that sets Memcache listening, I set here 11211, preferably more than 1024 ports,

The-c option is the maximum number of concurrent connections to run, the default is 1024, I set the 256 here, according to the load of your server to set,

-P is set to save memcache PID file, I am here to save in/tmp/memcached.pid,

6. If you want to end the memcache process, execute:

# Kill ' Cat/tmp/memcached.pid '

You can also start multiple daemons, but the ports cannot be duplicated.

7. Restart the Web service

/etc/init.d/lighttpd-flighttpd.conf Restart

8. Memcache Environmental test:

telnet localhost 11211

Save

Set

Good 32 0 10

HelloWorld

STORED

Retrieve

Gets good

VALUE Good 32 10 10

HelloWorld

END

Replace

Replace good 32 0 10

Worldhello

STORED

Get good

VALUE Good 32 10

Worldhello

END

Trailing add

Append Good 32 0 5

After

STORED

Get good

VALUE Good 32 15

Worldhelloafter

END

Add header

Prepend Good 32 0 6

Before

STORED

Get good

VALUE Good 32 21

Beforeworldhelloafter

END

Delete

Delete Good

DELETED

Get good

END

Installing the server

sudo apt-get install memcached

$ memcached-d-M 50-p 11211-uroot

The parameter description-m specifies how many megabytes of cache space to use;-p specifies the port to listen on;-u specifies which user to run

Installing the PHP module

sudo apt-get install Php5-memcache

Editing a configuration file

$ sudo vim/etc/php5/conf.d/memcache.ini

; Uncomment the next line to Enablethe module

extension=memcache.so

 

[Memcache]

memcache.dbpath= "/var/lib/memcache"

memcache.maxreclevel=0

memcache.maxfiles=0

memcache.archivememlim=0

memcache.maxfilesize=0

memcache.maxratio=0

 

$mem = new Memcache;

$mem->connect ("127.0.0.1", 11211);

$mem->set (' key ', ' This is amemcached test! ', 0;

$val = $mem->get (' key ');

Echo $val;