Raspberry Pi web server

[webpi 2]

I have a web site at Raspberry Web Server.  It's running headless, and I'm using Apache.  

 

I'm using a CMS that I wrote myself.  It's written in Python, and I've written some fairly advanced features like page caching and SEO friendly meta data.  

 

I'm only halfway through writing the back end.  I've written pages that I can use to adjust site settings and add new pages.  I need to write a few more scripts to do user management and manage all the pages in the site. 

 

I've set up an old PC as a load balancer, and I've just ordered three more Pies.  Soon I'll be running my site on a small cluster  .

[webpi 2]

I've built a Raspberry Pi cluster with 4 nodes.  Here's a picture:

 

[tjstroker 1]

I checked out your site. Nice information.

 

So a couple of questions. Why not try a PI for a load balancer with a USB Ethernet dongle as eth1? And why not use an NFS mount for shared web content, instead of each web server having duplicate content?

[webpi 2]

I've never worked with a load balanced server before, so I wanted to keep it fairly simple to begin with.  I didn't know how much processing power the load balancer would need so I thought I'd start with an old PC.  And I wanted to use all the Pies I have as server nodes.  When I can get my hands on another Pi I might try setting it up as a load balancer.  

 

I didn't use NFS because I thought this would increase the overhead on each file that gets served, and I didn't want the file server to be a bottleneck.  

 

Once I'm a bit more familiar with this technology I may well end up implementing the changes that you suggest.

[tjstroker 1]

Haha! Well I really wasn't suggesting, as much as was just curious. Looks good, and I would be interested in hearing about you Load balance if you push a PI that way.

[webpi 2]

I've been tuning Apache and making various improvements in my Raspberry Pi cluster.  I've unloaded unused modules, and increased the number of server processes.  

 

Testing with siege shows a reasonable increase in performance.   The maximum transaction rate used to be 460 transactions per second, but now it's around 940 transactions per second.

[webpi 2]

My cluster's been running quite nicely for a few months now.  Performance seems ok, but there's always room for improvement, so I did some on site optimization to make pages load more efficiently.  I hardly made any changes to the server configuration.  These tuning enhancements were all about modifying my CMS and the HTML template for my site. There's still room for improvement, especially with the Reddit sharing button, but I think performance is a lot better.  Some of the page plugins take a while to load, but the HTML for each page loads and renders pretty quickly.

[webpi 2]

I added four more nodes to my cluster and built new racks.  I'm monitoring it to see how performance has improved. Read the details here: http://raspberrywebserver.com/raspberrypicluster/adding-more-nodes-to-the-cluster.html

 

[anglenasalt 0]

NFS instead of each web server having duplicate content? 

[webpi 2]

It's important for my site to be as fast as possible, so I didn't want to add the overhead of serving content from NFS.  The script that I use to sync servers is pretty simple, and I've set up a button in the admin area of my site that I can click to sync the servers when I update the site.