What is the difference between Web Farm and Web Garden?

Web Farm
 This is the case where you have only one web server and multiple clients requesting for resources from the same server.
 But when are is huge amount of incoming traffic for your web sites, one standalone server is not sufficient to process the request.
 You may need to use multiple servers to host the application and divide the traffic among them. This is called “Web Farm”.
 So when you are hosting your single web site on multiple web servers over load balancer is called “Web Farm”.
 The below diagram shows the overall representation of Web Farms.
 

In general web farm architecture, a single application is hosted on multiple IIS Server and those are connected with the VIP (Virtual IP) with Load Balancer. Load Balancer IPs are exposed to external world to access. So whenever some request will come to server from clients, it will first hit the Load Balancer, then based on the traffic on each server, LB distributes the request to the corresponding web server. These web servers may share the same DB server or may be they can use a replicated server in the back end.
So, in a single statement, when we host a web application over multiple web servers to distribute the load among them, it is called Web Farm.

Web Garden

when we are talking about requesting processing within IIS, Worker Process (w3wp.exe) takes care of all of these.
Worker Process runs the ASP.NET application in IIS. All the ASP.NET functionality inside IIS runs under the scope of worker process.
 Worker Process is responsible for handling all kinds of request, response, session data, cache data. Application Pool is the container
 of worker process. Application pool is used to separate sets of IIS worker processes and enables a better security,
 reliability, and availability for any web application.

 Now, by default, each and every Application pool contains a single worker process. Application which contains the multiple worker process is called “Web Garden”. Below is the typical diagram for a web garden application.

In the above diagram, you can see one of the applications containing the multiple worker processes, which is now a web garden.
So, a Web application hosted on multiple servers and access based on the load on servers is called Web Farms and when a single application pool contains multiple Worker processes, it is called a web garden.

Create Web Garden in IIS 6 and IIS 7

 

For IIS 6, 

Right Click on Application Pool > Properties > Goto Performance Tab.

In the “Performance Tab” section, you would have one option called “Web Garden” where worker process sets to “1”, you can set the number of worker processes that you required.

For IIS 7, 

Right Click on Application Pool > Go To Advance Settings > In Process Model section, you will have “Maximum Worker Processes”. You can change it more than 1 to make it as a web garden.

 

Advantages of Web Farm

• It provides high availability. If any of the servers in the farm goes down, Load balancer can redirect the requests to other servers.
• Provides high performance response for client requests.
• Provides better scalability of the web application and reduces the failure of the application.
• Session and other resources can be stored in a centralized location to access by all the servers.

Advantages of Web Garden

• Provides better application availability by sharing requests between multiple worker process.
• Web garden uses processor affinity where application can be swapped out based on preference and tag setting.
• Less consumption of physical space for web garden configuration.