Как установить memcached на windows

Memcached is a high performance, in-memory key-value store or caching system. Its main purpose is to speed up web applications by caching database queries, contents, or other computed results.

Memcached is originally a linux application, but since it is open-source, it has been compiled for windows. There are two major sources for the pre-built windows binary: Jellycan and Northscale, and both versions can be used. The following are the download links for the memcached windows binaries:

• http://code.jellycan.com/files/memcached-1.2.5-win32-bin.zip
• http://code.jellycan.com/files/memcached-1.2.6-win32-bin.zip
• http://downloads.northscale.com/memcached-win32-1.4.4-14.zip
• http://downloads.northscale.com/memcached-win64-1.4.4-14.zip
• http://downloads.northscale.com/memcached-1.4.5-x86.zip
• http://downloads.northscale.com/memcached-1.4.5-amd64.zip

In versions earlier than 1.4.5, memcached can install itself as a service. However, the ability to run memcached as a service is removed since version 1.4.5. Therefore, the installation steps are divided into two categories, part A for memcached prior to version 1.4.5. and part B for memcached version 1.4.5 and later.

A) Installation of memcached < 1.4.5:

1. Extract the memcached windows binary to any directory.

2. In versions earlier than 1.4.5, memcached can install itself as a service. Run a command prompt with elevated privileges, and type:

   c:\memcached\memcached.exe -d install
   

   • Replace c:\memcached\memcached.exe with the actual path of your installation.

3. Then, start or stop the memcached service with the following command:

   c:\memcached\memcached.exe -d start
   c:\memcached\memcached.exe -d stop
   

4. To change the configuration of memcached, run regedit.exe and navigate to the key HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\memcached. Suppose you wish to increase the memory limit of memcached, edit the value of ImagePath to the following:

   "c:\memcached\memcached.exe" -d runservice -m 512
   

   • Besides -m 512, you may also append other memcached parameters to the path. Run c:\memcached\memcached.exe -h to view the list of available parameters.

5. Meanwhile, to uninstall the memcached serivce, run the following command:

   c:\memcached\memcached.exe -d uninstall
   

B) Installation of memcached >= 1.4.5:

1. Extract the memcached windows binary to any directory.

2. In version 1.4.5 or later, memcached cannot run as a service. It must be started as a normal process using the task scheduler. To configure the memcached process to run automatically every time windows start, run a command prompt with elevated privileges, and type the following:

   schtasks /create /sc onstart /tn memcached /tr "'c:\memcached\memcached.exe' -m 512"
   

   • Replace c:\memcached\memcached.exe with the actual path of your installation.
   • Besides -m 512, you may also append other memcached parameters to the path. Run c:\memcached\memcached.exe -h to view the list of available parameters.

3. Meanwhile, to remove the scheduled memcached task, run the following command:

   schtasks /delete /tn memcached
   

Integrating with PHP

To interface with memcached in PHP, you need to install the memcache extension for PHP:

1. Check that your PHP extension folder has the file php_memcache.dll. If not, download the file from https://pecl.php.net/package/memcache (select the windows dll file), and place it in the PHP extension folder.

2. Add the following line in php.ini to enable the memcache extension: extension=php_memcache.dll

3. Create this simple php script file to test that it works.

   <?php
   
   $memcache = new Memcache;
   $memcache->connect('localhost', 11211) or die ("Could not connect");
   
   $version = $memcache->getVersion();
   echo "Server's version: ".$version."<br/>\n";
   
   $tmp_object = new stdClass;
   $tmp_object->str_attr = 'test';
   $tmp_object->int_attr = 123;
   
   $memcache->set('key', $tmp_object, false, 10) or die ("Failed to save data at the server");
   echo "Store data in the cache (data will expire in 10 seconds)<br/>\n";
   
   $get_result = $memcache->get('key');
   echo "Data from the cache:<br/>\n";
   
   var_dump($get_result);
   
   ?>
   

Integrating with Python

To interface with memcached in Python, you need to install the memcached client for Python.

1. Execute one of the following command to install the memcached client. The first is for Python 2.x while the second is for Python 3.x.

   pip install python-memcached
   pip install python3-memcached
   

2. Create this simple python script to test that it works.

   import memcache
   mc = memcache.Client(['127.0.0.1:11211'], debug=0)
   mc.set("some_key", "Some value")
   value = mc.get("some_key")
   mc.set("another_key", 3)
   mc.delete("another_key")
   mc.set("key", "1")   # note that the key used for incr/decr must be a string.
   mc.incr("key")
   mc.decr("key")
   

Memcached statistics

To view the statistics for memcached, bring up a telnet connection to memcached by the command:

telnet 127.0.0.1 11211

Then, type stats and enter.

Here is an explanation of the different memcached stats.

Name	Type	Meaning
pid	32u	Process id of this server process
uptime	32u	Number of secs since the server started
time	32u	current UNIX time according to the server
version	string	Version string of this server
pointer_size	32	Default size of pointers on the host OS (generally 32 or 64)
rusage_user	32u.32u	Accumulated user time for this process (seconds:microseconds)
rusage_system	32u.32u	Accumulated system time for this process (seconds:microseconds)
curr_items	32u	Current number of items stored
total_items	32u	Total number of items stored since the server started
bytes	64u	Current number of bytes used to store items
curr_connections	32u	Number of open connections
total_connections	32u	Total number of connections opened since the server started running
connection_structures	32u	Number of connection structures allocated by the server
reserved_fds	32u	Number of misc fds used internally
cmd_get	64u	Cumulative number of retrieval reqs
cmd_set	64u	Cumulative number of storage reqs
cmd_flush	64u	Cumulative number of flush reqs
cmd_touch	64u	Cumulative number of touch reqs
get_hits	64u	Number of keys that have been requested and found present
get_misses	64u	Number of items that have been requested and not found
delete_misses	64u	Number of deletions reqs for missing keys
delete_hits	64u	Number of deletion reqs resulting in an item being removed.
incr_misses	64u	Number of incr reqs against missing keys.
incr_hits	64u	Number of successful incr reqs.
decr_misses	64u	Number of decr reqs against missing keys.
decr_hits	64u	Number of successful decr reqs.
cas_misses	64u	Number of CAS reqs against missing keys.
cas_hits	64u	Number of successful CAS reqs.
cas_badval	64u	Number of CAS reqs for which a key was found, but the CAS value did not match.
touch_hits	64u	Numer of keys that have been touched with a new expiration time
touch_misses	64u	Numer of items that have been touched and not found
auth_cmds	64u	Number of authentication commands handled, success or failure.
auth_errors	64u	Number of failed authentications.
evictions	64u	Number of valid items removed from cache to free memory for new items
reclaimed	64u	Number of times an entry was stored using memory from an expired entry
bytes_read	64u	Total number of bytes read by this server from network
bytes_written	64u	Total number of bytes sent by this server to network
limit_maxbytes	32u	Number of bytes this server is allowed to use for storage.
threads	32u	Number of worker threads requested. (see doc/threads.txt)
conn_yields	64u	Number of times any connection yielded to another due to hitting the -R limit.
hash_power_level	32u	Current size multiplier for hash table
hash_bytes	64u	Bytes currently used by hash tables
hash_is_expanding	bool	Indicates if the hash table is being grown to a new size
expired_unfetched	64u	Items pulled from LRU that were never touched by get/incr/append/etc before expiring
evicted_unfetched	64u	Items evicted from LRU that were never touched by get/incr/append/etc.
slab_reassign_running	bool	If a slab page is being moved
slabs_moved	64u	Total slab pages moved
crawler_reclaimed	64u	Total items freed by LRU Crawler
lrutail_reflocked	64u	Times LRU tail was found with active ref. Items moved to head to avoid OOM errors.

Source: https://github.com/memcached/memcached/blob/master/doc/protocol.txt

This article will teach you how to install and set up Memcached in both a Windows and Linux environment.

If you’ve already completed the installation process, you can also learn how to access and manage data in Memcached with PHP.

What is Memcached?

Memcached is a free, open-source memory caching system, often used for enhancing the speed of dynamic database-driven websites.

The cached data gets stored in a short-term, dynamic memory location that can be easily accessed within your applications by a key name.

Install Memcached on Windows

Memcached installation in a Windows environment is pretty straightforward.  There are just a few steps to follow.

There are two locations that you need to download from. The executable and supporting files GitHub repository, and the PHP extension from PHP’s official website.

First, we’ll start with the executable file and supporting files. You can download them from GitHub. They keep the repository updated regularly with the latest versions.

Make sure to download the correct files that your system will support, x64 vs. x86, etc., and place them in a directory on your local drive. My files are located on the C: drive at:

C:\memcached

Now, we need to head on over to the PHP PECL Downloads Page where you’ll see a long list of extension releases for PHP.

This list only contains a handful of Memcached Windows download links. The latest Windows download, at the time of this article, allows support for PHP versions 7.2 through 7.4. Download the file that fits your PHP environment description, x64 or x86, or thread-safe vs. non-thread-safe.

Move the newly downloaded DLL file to the location of your PHP installation and into the ext folder. Mine is located here:

C:\php\ext

In my case, I’ve downloaded the installation file for PHP 7.4, so my php.ini configuration will look like this:

[Memcache]
extension=php-7.4.x_memcache.dll
memcache.allow_failover = 0
memcache.chunk_size = 32768
memcache.default_port = 11211
memcache.hash_strategy = standard 
memcache.hash_function = crc32
memcache.protocol = ascii
memcache.compress_threshold = 20000
memcache.lock_timeout = 1

Make sure you’ve used the correct file name when updating your php.ini file. Yours could be different than what’s shown in this example and adding an incorrect file name will cause issues with the installation.

After you’ve downloaded and moved the DLL file to the correct location and updated your php.ini file, restart PHP by opening the Services app, or services.msc, and restarting the World Wide Web Publishing Service service.

[Ctrl+R]
services.msc

The final step is starting Memcached in your Windows environment by running the following command:

C:\memcached\memcached.exe -d start

Make sure you’re in the directory where the memcached.exe file is located before starting it, otherwise you’ll get an error. Alternatively, you could set up the path in your system’s environment variables to point to the correct directory so you can start it from anywhere in the command-line tool.

Install Memcached on Linux

There are two options for the first step of an installation in a Linux environment.  You can either download the file directly from the downloads page or you can run the wget command below, which will grab and download the latest version automatically to your current active directory:

wget http://memcached.org/latest

Next, you’ll need to unzip the downloaded tar.gz file:

tar -zxvf memcached-1.x.x.tar.gz

You’ll need to replace «1.x.x» with the version number that was downloaded. At the time of this writing, the latest version was 1.6.9, so the command would be tar -zxvf memcached-1.6.9.tar.gz

Now that the file contents are extracted, move over to the newly created directory, again using the correct version number in place of «1.x.x»:

cd memcached-1.x.x

Finally, complete the installation from the new directory:

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

That’s pretty much it. With my Linux/Apache environment, I had to restart Apache for the new installation to take effect within my PHP applications, but all you need to do is run this command to restart Apache:

sudo systemctl restart apache2

Conclusion

Memcached is a great solution for memory caching, in either a Windows or Linux environment.  Especially when querying heavy loads of data, or data that typically doesn’t change often.

Now that everything is setup in your environment, head on over to the next article to leverage the power of Memcached with PHP.