Guys,
Can any one explain how to use memcache in PHP? I would need installation procedures too.

Thanks in advance.

Durai.

hi all,

memcached is a high-performance, distributed memory object caching system.

used to store and retrieve cached data from distributed cached servers.

It can connect to a memcache server from a list of servers to store and retrieve cached data.

The memcache server that it connects depends on identifier of the key use to access each cached data item. So, data items are cached in different servers to distribute the load.


memcache methods:

Memcache::add -- Add an item to the server
Memcache::close -- Close memcached server connection
Memcache::connect -- Open memcached server connection
memcache_debug -- Turn debug output on/off
Memcache::decrement -- Decrement item's value
Memcache::delete -- Delete item from the server
Memcache::flush -- Flush all existing items at the server
Memcache::get -- Retrieve item from the server
Memcache::getStats -- Get statistics of the server
Memcache::getVersion -- Return version of the server
Memcache::increment -- Increment item's value
Memcache:connect -- Open memcached server persistent connection
Memcache::replace -- Replace value of the existing item
Memcache::set -- Store data at the server


eg code:

//create instance for memcache
$memcache = memcache_connect('host', 11211);

// to store value to memcache
$memcache->set("str_key", "String to store in memcached");

// to get the stored value from memcache
$vFromCache = $memcache->get('str_key');


Installation in command line option:

# ./memcached -d -m 2048 -l 10.0.0.40 -p 11211

hi raj,
this article is very nice and very useful to reduce the weight of the web server to load more items to be displayed at same time
it seems that memchache is used as virtual memory or memory mediator.
am i correct?
can we have to connect some 5 memcache servers with one web server?

is there any api is to be installed for enabling this?

__________________
With,
J. Jeyaseelan
Everything Possible

hi,

1. we can use more than 5 servers for memcache.

$options["servers"] => we can give number of memcache servers by an array

eg:

$options["servers"] = array("10.0.0.15:11000","10.0.0.16:11001");
$memc = new MemCachedClient($options);

$memc = new MemCachedClient($options);


2. we need to install API memcache.

-> Api & More information you can see from this site

memcached: a distributed memory object caching system

Memcache main purpose decrease database load in dynamic web applications.

Example:

Site viewed by more than 100 users simultaneously, a lot of memory
will be loosed for saving the search results as arrays, and you need to execute the database query again and again.

If you can save the intermediate array after the queriying and execution for a particular period of time, you can reuse this array for further queries for a particular period. The php function memcache is using for this purpose.

$a = array(1,2,3,4,5);

$mmc = new Memcache;

$mmc->connect(’127.0.0.1′ ,11211 ) or die (”Could not Connect”);

echo $mmc->getVersion();

$mmc->set(’myarray’,$a, false, 60); // the value will be saved with key
array for 60 seconds
print_r ( $mmc->get(’myarray’) ) ;

here i listed the memcached installation steps ....

#!/bin/sh

##
# Install memcached and dependencies smoothly on Mac OS X.
#
# Newer versions of these libraries are available and may work better on Mac OS X.
#
# See also http://topfunky.net/svn/shovel/memca...ached-linux.sh
#
# USE AT YOUR OWN RISK.
#
# AUTHOR: Geoffrey Grosenbach Nuby on Rails | Ruby on Rails for Newbies
#
# Some fixes are from Fast memcached on OS X
#
# AFTER RUNNING THIS SCRIPT:
#
# Set the environment variable EVENT_NOKQUEUE to 1
# * csh and derivatives: setenv EVENT_NOKQUEUE 1
# * sh and derivatives (like bash): export EVENT_NOKQUEUE=1
#
# You may also need to add /usr/local to your PATH.
#

PREFIX=/usr/local

mkdir src
cd src

# Install libevent dependency
curl -O http://www.monkey.org/~provos/libevent-1.1b.tar.gz
tar xfz libevent-1.1b.tar.gz
cd libevent-1.1b
./configure --prefix=${PREFIX} && make
sudo make install
cd ..

# Install memcached and fixes
curl -O http://www.danga.com/memcached/dist/...-1.1.12.tar.gz
tar xfz memcached-1.1.12.tar.gz
cd memcached-1.1.12
./configure --prefix=${PREFIX}

# in Makefile
# LDFLAGS = -L/lib
# LDFLAGS = -L${libdir}
sed -e 's/-L\/lib/-L${libdir}/' Makefile > Makefile.new
mv Makefile.new Makefile

# also in Makefile
# CFLAGS = -g -O2 -I/include
# CFLAGS = -g -O2 -I${includedir}
sed -e 's/-I\/include/-I${includedir}/' Makefile > Makefile.new
mv Makefile.new Makefile

# insert in memcached.c...
# #undef TCP_NOPUSH
# #ifdef TCP_NOPUSH
curl -O http://topfunky.net/svn/shovel/memca...memcached_c.rb
ruby fixmemcached_c.rb > memcached.c.new
mv memcached.c.new memcached.c

make
sudo make install
cd ../..

echo "Installation complete. Please add EVENT_NOKQUEUE=1 to your shell environment."

__________________
Thanks & Regards
Sabari...

hi,


Refer this link:

Installing memcached | Development, Analysis And Research