This is a follow-on to my previous post about determining significant digits, or sigdigs, in performance and capacity planning calculations. Once we know how to do that, inevitably we will be faced with rounding the result of a calculation to the least...
The other day, I stumbled upon the signif function in R, so I thought I'd take a look at what it does and compare it with some results discussed in Chap. 3 "Damaging Digits in Capacity Calculations" of my GCaP book, viz., Example 3.5 on page 31. The m...
This tutorial covers profiling of Linux servers using open-source tools such as "iostat", "oprofile" and "blktrace". Both processor-bound and I/O-bound cases are covered, and the emphasis is on tools that provide visual displays of relevant metrics. Li...
Download "Getting Started with the Social Media Analytics Research Toolkit" (pdf, 1.25 megabytes) Download the Social Media Analytics Research Toolkit Media Inactivist, Thought Follower, Sit-Down Comic, Social Media Analytics Researcher, Former Boy Gen...
Recently, several performance engineers, who have been applying my universal scalability law (USL) to their throughput measurements, reported a problem whereby their Excel spreadsheet calculations produced a negative value for the coherency parameter (...
It’s been a long time since I posted here, for a number of reasons: Change of focus from Ruby programming to Linux capacity planning, especially in the realm of I/O subsystems. You’ll find more about that at http://linuxcapacityplanning.com...
PDQ (Pretty Damn Quick) major release 5.0 is on the launch pad at Cape SourceForge. Because of a potential collision with the North Korean ICBM/satellite launch, we won't be filling the main liquid-hydrogen tank until next week (we don't want PDQ blame...
Zero Inflated Models and Generalized Linear Mixed Models with R.
Zuur, Saveliev, Ieno (2012).
