… doing performance analyzes you often would want to see 95 percentile, 99 percentile and similar values. The “average” is the evil of… response time goal in 95 or 99 percentile is much better. Say you say 99 percentile response time should be one second… and you observe certain 99 percentile response time on the backend it is often 99.99 percentile response time which is a…
Post: Color code your performance numbers
June 2, 2010 By 4 Comments
… computed using built in aggregate functions. We most likely would like to see some percentile numbers – 95 percentile or 99 percentile. The problem is computing…
Post: The two even more fundamental performance metrics
May 5, 2011 By 6 Comments
… time minus the arrival time (a duration). We can also compute the average concurrency, throughput, response time, and utilization during the… the previous post for how to compute these practically for free. However, we can also compute a number of other very interesting… seen how to compute up to this point. You can calculate the standard deviation, the median, any desired percentile (depending on how…
Post: Virtualization and IO Modes = Extra Complexity
March 21, 2011 By 12 Comments
… 4.0.4 running on Windows 7 on my desktop computer with pair of 7200 RPM hard drives in RAID1. Because…: 0.04ms avg: 0.06ms max: 0.34ms approx. 95 percentile: 0.06ms Threads fairness: events (avg/stddev): 1343.0000/0…: 0.10ms avg: 1.11ms max: 259.69ms approx. 95 percentile: 5.31ms Threads fairness: events (avg/stddev): 33900.0000/0…
Post: Introducing tcprstat, a TCP response time tool
August 31, 2010 By 12 Comments
…, but we’ve chosen the statistics carefully so you can compute meaningful things about your TCP traffic. What is this good…, in microseconds. These are repeated for the 95th and 99th percentiles as well. Other metrics are also available. Here’s a…
