Browsing articles in "Algorithms"

Using the XenServer Java API to launch a VM

Aug 12, 2012   //   by Daniel Kranowski   //   Algorithms  //  2 comments

Citrix XenServer has a management API which lets you control every aspect of your hypervisor: hosts, guest VMs, networks, storage. The API has bindings to multiple languages, including Java. Apache CloudStack integrates with XenServer and since CloudStack is written in Java it makes extensive use of the XenServer Java API. If you’re interested to see an example of how to use the XenServer Java API to launch a VM, take a look at this article I just wrote for cloudspring.com Read more >>

Making the CloudStack "Quick Install" quicker

Jul 8, 2012   //   by Daniel Kranowski   //   Algorithms  //  1 comment

After preparing Apache CloudStack according to the directions in the “Basic Installation Guide”, which is also called the “Quick Install Guide”, you’re supposed to login to the management server web ui and “provision your cloud infrastructure.” The web ui’s Basic Installation wizard takes you through 17 screens before you get to click the Launch button and actually deploy system VMs onto your hypervisor. The Guide is definitely helpful but I think it would be even more helpful to see some concrete examples of what you could enter into the 17-screen wizard. Below are some example values you can enter into the wizard to get some quick satisfaction with CloudStack. Read more >>

Timing races in Selenium 2: implicit waits vs explicit waits

Jan 14, 2012   //   by Daniel Kranowski   //   Algorithms  //  8 comments

The most common debugging experience in automated Selenium testing is the ubiquitous timing race, where your code is rushing to access a WebElement that hasn’t been fully loaded into the driver yet. If you’re stepping through the test one line at a time it will work just fine, but when you let it run in batch mode at its own speed, then it crashes with a complaint like NoSuchElementException. When you’ve got a suite of a hundred or more Selenium testcases you definitely don’t want to step through them one line at a time, it needs to be automated.

The timing race stems from the fact that Read more >>