Znn.com News System
Description
[[Description of Znn.com]]
Relevance: Slashdot Effect
The motivation for the Znn.com instantiation comes from an Internet phenomenon known as theSlashdoteffect, where an otherwise low-traffic website, shortly after being featured on slashdot.org, gets inundated with visitors for a period of time, anywhere from a few hours to a couple days [Ter04]. Now a common term, it describes a similar phenomenon where a website experiences a sudden, unanticipated rise in requests due to a popular event (or sometimes, anticipated, but not to the scale observed), for example, breaking news or superbowl craze [Wik08d]. To illustrate a few instances, on the morning of August 17, 2006, a break in the JonBenet Ramsey case resulted in a local news website, rockymountainnews.com, being swamped by news readers. Browsing the site at 10:18 AM took more than 2 minutes to retrieve a blank page with only the local weather showing in the corner. On September 4, 2006, the shocking death of Steve “Crocodile Hunter” Irwin caused the Australian Broadcasting Corp website to be temporarily shut down; similarly, numerous other news sites groaned to a halt. Of note is that Australian Broadcasting Corp’s site resumed a few hours later with a low-bandwidth format to cope with the high traffic [Tai06]. A more problematic, revenue-losing case arises when an e-commerce site is shut down by the Slashdot-like effect, as exemplified by Wal-Mart’s shopping site on Black Friday 2006, which remained inaccessible into the afternoon after the initial morning rush [San06, Sch06]. The Australian Broadcasting Corp illustrates the present coping mechanism of most website administrators to the Slashdot effect. When they first notice a sudden rise in visit requests, they make a decision to temporarily shut down the site for manual reconfiguration, where usually entails resorting to lower fidelity content. In extreme cases, the site might temporarily shut down or simply post a notice to “visit later.” There are a number of disadvantages with this scheme:
- The problem may not be discovered in time;
- The manual process means slower response time;
- The chosen solution may be suboptimal; and
- It may result in a potential loss of confidence, revenue, or future business.
An ideal approach would be to achieve site adaptation automatically, and our aim is to demonstrate such self-adaptation with the Znn.com instantiation. It is worth noting that a few modern systems with sophisticated infrastructures, such as Google Gmail, have equipped themselves with similar but limited adaptation capabilities, for example, to instruct its users to “reload in a few seconds” when it detects a sudden peak or other underlying connectivity issues to its servers.
Quality Concerns
Fidelity, performance, cost
Implementation
System prerequisites
Other software used
Installation
Running slashdot simulation
Solutions
[RainbowZnn Rainbow]