October 21, 2005
Symmetry's Birthday Surprise
By David Harris
When the tenth issue of symmetry magazine came
out on October 12, 2005, the magazine’s Web server crashed unexpectedly.
The reason became instantly obvious when looking at the server
statistics—symmetry had been ‘slashdotted’.
Well-known to tech-savvy Web users,
slashdot.org highlights sites of interest around the Web, causing
tens of thousands of devoted readers to check out the recommendations.
And so, when the gallery of particle physics art from the latest
symmetry was linked to the front page of slashdot, our server could not
initially handle the demand since it was set to accept only 175
simultaneous connections—usually more than enough. Within minutes, the
Web server was reconfigured and ready to handle the flow of readers from
slashdot. And flow they did, with nearly 30,000 unique visitors in the
first four hours after appearing on slashdot. Servers regularly crash
when they are unexpectedly bombarded like this; the phenomenon is even
known as the slashdot effect.
The chart below shows the number of visitors per day through the start
of October. It peaks at nearly 30,000 on October 12, with another 20,000
visitors on the following day. Traffic dropped off as the story left
slashdot’s front page but residual traffic is still higher than earlier
in the month.
If there is any good reason for a web server to crash, it is because of
sudden great interest, and the symmetry team found it a welcome way to
celebrate one year of publishing the magazine.
The Stanford Linear Accelerator Center is
managed by Stanford University for the
US Department of Energy
Friday October 21, 2005 by