Click here to Skip to main content
Click here to Skip to main content

Memcached (Distributed Cache) ASP.NET Provider

, 31 Dec 2007
Rate this:
Please Sign up or sign in to vote.
Provider for using Memcached in a web farm.

Introduction

Currently I am working on a web-based project that will be hosted in a web farm. Among several issues, we faced the issue of having a distributed cache. As we know, the current cache in ASP.NET is an in-process cache and can't be used in a web farm. After doing some research, we found a few solutions on the web but at the end, all of them had scalability issues. We found a few third party implementations but they were quite expensive. Then I came across the Memcached implemented by Danga Interactive. This is a high performance distributed memory cache initially implemented for http://www.LiveJournal.com. The original implementation runs on a *nix system. Luckily there is Win32 port available at http://jehiah.cz/projects/memcached-win32/ for those who want to run it in a Windows environment. For more details on the working of Memcached, please read the following article: http://www.linuxjournal.com/article/7451.

There is a C# client for Memcached available and can be downloaded from the following location: https://sourceforge.net/projects/memcacheddotnet/. For coding this provider, I have used clientlib 1.1.5.

Using the Code

Following is the interface for the Cached Provider:

public abstract class CacheProvider : ProviderBase
{
    // Currently returns -1 as this property is not implemented
    public abstract long Count { get;}
    // Returns the server names with port in the memcached cluster
    public abstract string[] Servers { get;}
    // Default expiration time in milli seconds
    public abstract long DefaultExpireTime { get;set;}
    // Adds object to the cache for the max amount of time
    public abstract bool Add(string strKey, object objValue);
    // Adds object to the cache for Default Expire time if bDefaultExpire
    // is set to true otherwise for max amount of time
    public abstract bool Add(string strKey, object objValue,bool bDefaultExpire);
    // Add objects for specified about of time. Time is specified in milli seconds        
    public abstract bool Add(string strKey, object objValue, long lNumofMilliSeconds);
    // Return the object from memcached based on the key otherwise 
    // just returns null
    public abstract object Get(string strKey);
    // Clears everything from the cache on all servers
    public abstract bool RemoveAll();
    // Removes the an object from cache
    public abstract object Remove(string strKey);
    // Release resources and performs clean up
    public abstract void Shutdown();
    // Checks if the key exists in memory
    public abstract bool KeyExists(string strKey);
    // Return all servers stats
    public abstract Hashtable GetStats();
}

Following is how to configure the Cache Provider in a web.config or app.config file:

<?xml version="1.0" encoding="utf-8" ?>
<configuration>

 <configSections>
  <section name="cacheProvider"
      type="CacheProvider.CacheProviderSection, CacheProvider"
      allowDefinition="MachineToApplication" 
      restartOnExternalChanges="true"/>
 </configSections>

 <cacheProvider defaultProvider="MemcachedCacheProvider">
  <providers>
   <add name="MemcachedCacheProvider" 
       type="CacheProvider.MemcachedCacheProvider,CacheProvider"
       servers="127.0.0.1:11211" 
       socketConnectTimeout="1000" 
       socketTimeout="1000"/>

   <!—To add more servers use comma to separate servernames and ports
   eg. servers="127.0.0.1:11211,192.168.0.111:11211"
   -->

  </providers> 
 </cacheProvider>
</configuration>

The following parameters can be specified for initializing the cache provider:

  • socketConnectTimeout – Timeout for socket connection with Memcached servers
  • socketTimeout – Timeout for socket read-write operations
  • defaultExpireTime – Default expire time in milliseconds

To use the Cache Provider in a project, add a reference to CacheProvider.dll and access the methods using the DistCache static class. When creating keys for storing data, avoid using spaces in keys, e.g., "My Key". This is an issue with the C# Memcached client. To close the provider gracefully, add a call to DistCache.Shutdown() in Global.asax file's Application_End event.

Update Dec 24, 2007: To report any issues and enhancements, please go to the following link: http://www.codeplex.com/memcachedproviders. I have started working on the Session State Provider for Memcached. I will be releasing it very soon on CodePlex.com.

Update Dec 31, 2007: I have released the Session State Provider for Memcached. Please go to the following link to download: http://www.codeplex.com/memcachedproviders.

References

  1. http://www.danga.com/memcached/
  2. http://jehiah.cz/projects/memcached-win32/
  3. https://sourceforge.net/project/showfiles.php?group_id=152153
  4. Sample Project Provider by Memcached C# client 1.1.5
  5. http://www.infoq.com/news/2007/07/memcached
  6. http://msdn2.microsoft.com/en-US/library/aa479038.aspx
  7. http://www.linuxjournal.com/article/7451

License

This article, along with any associated source code and files, is licensed under The Apache License, Version 2.0

About the Author

Fahad Azeem
Web Developer
United States United States
My name is Fahad Azeem. I am interested in distributed software development. Currently I am working for a software consulting company in Chicago which developes software in .NET platform.
 
My Blog: http://fahadaz.blogspot.com

Comments and Discussions

 
GeneralA Free distributed cache PinmemberWes Malik26-Jan-11 18:06 
GeneralMy vote of 1 Pinmemberericliu668813-May-10 7:22 
Generalhttp://sharepointcache.codeplex.com/ PinmemberIaxiomI14-Feb-10 5:02 
QuestionHow to get this work with MemcachedProvider 1.2 and ASP.NET 3.5?? PinmemberMaxi Ng @ TW21-Oct-09 20:38 
GeneralMy vote of 2 PinmemberMaxi Ng @ TW21-Oct-09 20:35 
Generalwell done your implementation Pinmemberschuetz23-Sep-07 4:13 
QuestionIs the Cache in Asp.net 2.0 implemented with a provider model? PinmemberTormodHystad16-Aug-07 4:17 
AnswerRe: Is the Cache in Asp.net 2.0 implemented with a provider model? Pinmemberl0t3k21-Aug-07 7:11 
GeneralRe: Is the Cache in Asp.net 2.0 implemented with a provider model? PinmemberFahad Azeem4-Feb-08 11:11 
GeneralNunit CheckExpire_TimeSpan_Positive_Test Error PinmemberVercors8-Aug-07 2:22 
GeneralRe: Nunit CheckExpire_TimeSpan_Positive_Test Error Pinmemberzhaodengpan8-Oct-07 23:17 
GeneralRe: Nunit CheckExpire_TimeSpan_Positive_Test Error PinmemberVercors9-Oct-07 3:35 
QuestionHow about using webfarm for sessionstate ? PinmemberKent Liu30-Jul-07 16:40 
AnswerRe: How about using webfarm for sessionstate ? PinmemberFahad Azeem31-Jul-07 4:10 
GeneralRe: How about using webfarm for sessionstate ? Pinmemberschuetz23-Dec-07 15:43 
GeneralRe: How about using webfarm for sessionstate ? PinmemberFahad Azeem23-Dec-07 18:16 
GeneralRe: How about using webfarm for sessionstate ? PinmemberFahad Azeem24-Dec-07 4:47 
GeneralRe: How about using webfarm for sessionstate ? PinmemberNurhakKaya15-Aug-12 3:37 
GeneralRe: How about using webfarm for sessionstate ? PinmemberNurhakKaya15-Aug-12 21:23 

General General    News News    Suggestion Suggestion    Question Question    Bug Bug    Answer Answer    Joke Joke    Rant Rant    Admin Admin   

Use Ctrl+Left/Right to switch messages, Ctrl+Up/Down to switch threads, Ctrl+Shift+Left/Right to switch pages.

| Advertise | Privacy | Mobile
Web01 | 2.8.140721.1 | Last Updated 31 Dec 2007
Article Copyright 2007 by Fahad Azeem
Everything else Copyright © CodeProject, 1999-2014
Terms of Service
Layout: fixed | fluid