YUI-LIFE

Edit: Dreamhost PS has a new “Lighttpd” server configuration that reduces CPU and memory usage. However, it is not compatible with .htaccess URL rewrites which are used by many PHP scripts. Even so, this configuration can be used as a base for the Litespeed install to reduce memory usage past the Apache-as-proxy configuration.

1. Change to lighttpd in https://panel.dreamhost.com/?tree=vserver.settings

2. Edit the lighttpd configuration file in /home/username/lighttpd with server.port = 3000

3. Restart the VPS to unbind lighttpd from port 80

4. Install litespeed as below, ignoring the proxy step.

Dreamhost PS can act as a very cost effective VPS setup if you are able to configure it correctly. For $15.00 a month on top of the generous Dreamhost shared hosting plan, you can move off of the horrendously loaded shared webservers and onto a virtual private server with 150 MB RAM, 150 MB swap memory, and 150 MHz of dedicated CPU. Dreamhost’s MySQL database servers are still shared with others, but they are decent enough for most sites, and the fact that they are off-server means that they don’t use precious VPS memory.

Dreamhost PS’s default configuration was inherited directly from their shared hosting setup. It was slightly fiddled with but never fully optimized for low memory situations, which is what we have with Dreamhost PS. In particular, the Apache prefork threads that manage web connections to clients are compiled with libraries that you probably don’t need for your personal site. Because of this, more than 2MB of RAM are wasted per thread, and a moderately popular website usually has 30 or more threads. Also, the FastCGI settings are crude, leading to out-of-memory errors and debilitating “blocking” load from common FCGI daemons such as PHP, Perl, and Ruby.

There is much instability when running Dreamhost PS at the lowest memory settings. The easiest solution to this problem is to scale up the CPU/Memory of the Dreamhost PS server until it reaches acceptable levels, and pay extra month after month. A more cost-effective solution is to install an alternative web server behind Dreamhost’s Apache mod_proxy setup. The Litespeed web server is fast, stable, and .htaccess rewrite compatible so it’ll work straight out of the box with your Wordpress or Gallery or phpBB.

First, we’ll install the Litespeed Standard Edition web server to our home directory. The free Litespeed Standard Edition has a low connection limit of 150 and is more like trial software. However, since all of our web connections will be routed through Apache’s front-end mod_proxy module, Litespeed will never reach that limit, and we will never have to purchase Litespeed’s Enterprise Edition. Using Litespeed behind a proxy server makes for a slick deal.

Connect to your PS server’s shell account using SSH.

Using the command prompt, download the Litespeed web server:
wget http://www.litespeedtech.com/packages/3.0/lsws-3.3.4-std-i386-linux.tar.gz
Unzip it to a directory in your home:
tar -xzf lsws-3.3.4-std-i386-linux.tar.gz
Run the install, agreeing to the license and following the instructions:
lsws-3.3.4/install.sh

The Litespeed configuration server will automatically start after the install. Load the LiteSpeed Web configuration panel by browsing to domain.com:7080/

The important settings that you’ll need to configure to get started are .htaccess overrides and file paths. Under Server’s htaccess allow override, untick None and set the overrides that you require. FileInfo is important, as it controls permalinks and mod_rewrite ability. In Virtual Host’s general tab, untick all htaccess overrides to inherit the settings from Server. To set up file paths, edit the Virtual Host Root in the Basic tab to /home/YOURUSERNAME/. Edit the Document Root in the General tab to $VH_ROOT/yourdomain.com/

That should be enough to begin! Perform a graceful restart of Litespeed and test your site by browsing to yourdomain.com:8088.

If it works, we move on to Dreamhost’s control panel to finalize the configuration. In the Domains “Mongrel and Proxy” page, proxy your entire domain to port 8088.

In the Goodies “Cron Jobs” page, add a new cron job that initializes Litespeed after every server reboot: /home/yourusername/lsws/bin/lshttpd start

Wait a few minutes, and Litespeed should be serving the site on the default web port of 80. To check if it worked, use curl to grab the web page headers, and it should read “Litespeed” instead of “Apache”:
curl -I yourdomain.com

You’ll notice that all of your Apache threads are now lighter. They only use about 6MB RAM in mod_proxy mode instead of Dreamhost’s normal 8MB.
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We’ve taken a big step towards optimizing performance, but we’re not done yet. Litespeed comes standard with PHP4 for your popular web applications such as Wordpress, Gallery2, and phpBB. Next time, we’ll compile Litespeed’s PHP5 LSAPI with eAccelerator for top PHP performance.

This entry was posted on Tuesday, February 12th, 2008 at 7:32 pm and is filed under survivalgames. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.