When adding virtual CPU cores is the wrong thing to do

I was recently involved in a trouble shooting exercise where an application was giving terrible response times and frequent connection timeouts to visitors.  This particular application has peak traffic demands during the business day and very few users overnight.  From the checks I made using top and process status reports, it was easy to see that this virtual linux machine was saturated.  Multiple virtual CPUs running 99% user+system and a run queue length over 30.
Click read more for why adding more vCPUs was not a good idea.

Runnning XEN on ASUS X54C under Debian

I had a need to verify a new puppet configuration and wanted my own puppet master and client server to do this.  And, I wanted to be able to work on this when I was mobile.  
Solution: Run a debian XEN host and two Virtual Machines on the ASUS X54C laptop.   Here are my notes for making this work.

Hosting in bandwidth constrained situations

Hosting web sites has never been less expensive, but often there are constraints that when exceeded can dramatically increase your cost.
One of the key areas to manage is bandwidth.  I recomend to my clients that they be aggressive in allowing only  the major search engines and their targeted visitors access to their site.   Conserving and protecting bandwidth in this manner can keep you in the low cost tier and has a secondary advantage of reducing noise in traffic reports.
Read more to learn specific recomendations or Contact Me to assist with your site.

Drupal version control using subversion and Acquia Dev Desktop

We are big fans of drupal and continue to be amazed at the powerful and gorgeous web sites that can be created by this tool.
However, managing change and version control can be challenging.  And how do you make that database available to your developers?
Read more for a method of integrating production linux servers, subversion and the Acquia dev desktop to allow control over code and make available a synchronized environment for developers.


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