Michael Schwern talks about Perl5’s shortcomings, and explains how perl5i can overcome many of them – it is a pragma to fix as much of Perl 5 as possible all at once. While I haven’t worked with perl5i much, I wanted to talk about something Schwern talked about that resonated with me, and that’s the concept of “tribal knowledge.”
Last night, someone posed a problem in #perl-help. They wanted to have syntax highlighting in their shell for Perl code. I immediately suggested that they use Pygments – I knew about it because I’d used it before, and I had experimented with the command line tool. But I was surprised there wasn’t already a Perl solution.
chromatic identified some reasons why it is difficult to hire great Perl programmers, and then followed it up with some advice for hiring managers. They suggest a series of questions every good Perl programmer should be able to answer. I wanted to know how I stacked up.
Load averages are at once hugely simple and hideously complex. Understading what these numbers mean is important for correctly applying this simple indicator of system health.
First, a load average is not CPU percentage. That is simply a snapshot of how often a process was found being executed on the CPU. The load average differs in that it includes all demand for CPU, not just what is currently running.
A four-processor machine can be visualized as a four-lane freeway. Each lane provides the path on which instructions can execute. A vehicle can represent those instructions. Additionally, there are vehicles on the entrance lanes ready to travel down the freeway, and the four lanes either are ready to accommodate that demand or they’re not. If all freeway lanes are jammed, the cars entering have to wait for an opening. If we now apply the CPU percentage and CPU load-average measurements to this situation, percentage examines the relative amount of time each vehicle was found occupying a freeway lane, which inherently ignores the pent-up demand for the freeway – that is, the cars lined up on the entrances.
I’m a Perl guy. I like the language a lot – how it looks, how it works… Even if it isn’t perfect, I like it a lot. But I also love things that work, and Wordpress works.
This essay was originally written in Portuguese, and subsequently translated to English. I rewrote the English version so it reads like an anglophone wrote it.
I understand that some people have problems switching from Windows to linux. Since all my friends keep telling me how great Windows is, I thought I’d try an experiment.