Technology Insights

Find Out The Amount Of Time A Linux Process Has Been Running

I always forget the ps command arguments to see the length of time that a Linux process has been running so I am writing it out here in hopes of remembering it in the future without having to read the ps manpage. I also will know I can easily search this later to find the solution. Below I describe what command to use from a Linux terminal window to display the length of time a specific process or set of processes has been running.

Technology Insights

Find Out What Applications Are Installed From An RPM Package On Linux

Earlier today I was upgrading some packages on a CentOS Linux server and was curious what applications were actually installed with the coreutils RPM package. I knew that this was one of the main RPM packages that had a ton of various applications installed with it however I was not sure specifically which ones. Below are some examples of how to use RPM to find out exactly what is installed with a specific RPM package.

Technology Errors

Upgrade Redmine Rake Migrate Error: uninitialized constant ActionController::AbstractRequest

I ran into an issue earlier where adding a sub project to an already existing Redmine project produced an error and after a little bit of troubleshooting determined that upgrading Redmine would resolve the issue. During the upgrade process I ran into some other issues including a specific migration error using rake that is noted below. The upgrade process involved upgrading Redmine 0.8.3 to Redmine 0.9.3.

Technology Insights

PostgreSQL Log Entries: CDTLOG: statement: SHOW client_min_messages

I was troubleshooting an issue at work the other day regarding some PostgreSQL connections that were not closing. They were left IDLE, never closed, and eventually used up all of the possible connections (which totaled 100) configured in the  postgresql.conf configuration file. In the process of troubleshooting I noticed a bunch of Postgres log entries that I was unable to immediately pin down to what was causing the entries. Below I describe the view of the idle Postgres connections, the PostgreSQL log entries that were unfamiliar, and the cause of both.

Technology Insights

How to get a Linux Style Enviorment in Windows with Cygwin

Alex and I got some new laptops the other day. I have been a Linux user primarily for many years but the laptop came with Windows 7 so I decided to give it a spin. I must say on the whole I have to say it is a very fast and usable operating system. There is just one thing I was missing and that was Linux shell commands in the terminal. Nothing fancy but I am so used to using ls,rm and grep that I almost went back to Linux. But then Alex mentioned something about adding Cygwin to his laptop which I am of course familiar with but he also mumbled about adding it to the path. I had never even considered this, so I did it and wow is it cool. All the commands I love are in my terminal now. Plus if you use console.exe you can have tabs and every thing.