If you asked me what 90-9-1 was back in 1992, I might have told you it was my favorite DC radio station (WHFS). In the context of performance, specifically response times 90-9-1 is a new way to define performance thresholds. The first data points (90) represents 90% of response times during a performance test returning in 0 to 2 seconds. The second data point (9) represents 9% of response times returning in 2 to 10 seconds. The third and final data point (1) is for 1% in which we accept response times greater then 10 seconds. We could technically throw in a second 1 at the end (90-9-1-1) to represent a 1% failure rate that we potentially will accept during a performance test.
Take a look at a blog of mine from a few weeks back where I debate our abandonment thresholds. I’ve had a few weeks to really think through this blog entry. Since then I’ve had the opportunity to watch the team collect 90-9-1 metrics for our 9.0 PVT and the Dell/VMWare benchmark, as well as present at BbWorld about performance forensics. The more and more I think about responsiveness in the application, the less I am willing to cross the 10 second barrier.
10 seconds is an eternity. It’s the equivalent of response time purgatory…Well maybe not that bad, but still 10 seconds is a long time. Why don’t you count to 10 and tell me how annoyed you are at the end of the count…This blog isn’t even 10 seconds long. I guess only if you can read as fast as the Micro Machines Guy.