Slashdot Effect

Slashdot Effect:

"For those that have not heard of the Slashdot Effect, it occurs when your web site is mentioned on the front page of a story on slashdot.org which is very popular since it is the "news for nerds" site. Because thousands of web surfers will click on your site within an hour of it being posted, it really stresses your web server (and network connections) and often results in your web site becoming unresponsive ... or a "smoldering pile of rubble" due due to the slashdot effect. Note that any heavily trafficked site can generate lotsa inbound traffic to your web server, so technically the "slashdot effect" is a generic term referring to this phenomena of a large increase in "flash" traffic, often times resulting in a (basically) Distributed Denial of Service.

The Slashdot thundering herd has made several "visits" to my web site - in 2002 & 2003 for my christmas lights and christmas webcam and then in 2004 for my halloween decorations and halloween webcam. My ISP popped a 40-amp circuit breaker in 2002 (really did happen!), but you can read my writeups of the:

* Christmas 2003 Slashdot Effect Analysis
* Halloween 2004 Slashdot Effect Analysis
* Christmas 2004 Slashdot Effect Analysis

While numerous folks have written about the Slashdot Effect, this was a little different in that not only was it a test of "digital" stuff like the web server, ISP bandwidth, Perl/CGI code, but also "analog" stuff as the code has interfaces to various sensors and the webcam itself, plus you are turning a lotta lights ON & OFF - it certainly provided one heck of a light show for the neighbors! ;-)

Christmas/2004 Update: Now using mod_perl ... shoulda done this a long time ago - ApacheBench testing shows CGI is now capable of 20 requests/second versus 4 using cgi_exec ... so this rocks ... and even uncovered a coding boo-boo where I forgot to close a lock file in a certain case - but I'm sure there are few others that will pop-up in "stress" testing. And once I disabled KeepAlive in httpd.conf, the 2.4 GHz XEON (with a Gbyte of RAM) held up pretty darn decently to not one, but two waves of (inter)national media attention as the christmas lights webcam hoax was revealed. "