General Concepts » Eventual Consistency

Eventual Consistency

cloudstep makes many calculations in order to generate a reliable financial model.  Every time a change is made or a new element is added any Elements related to that change must be recalculated.

This process takes time and in order to allow you to continue to use the application making more changes a background worker goes along and tends your financial model making changes as needed.  Think of it as a robotic accounts person that hoovers up your changes and puts them in a giant ledger.

How do I know when its finished?

cloudstep might make lots of changes when you change one little thing.  For instance if you change your policy for AWS EC2 instances to be only on-demand pricing then every EC2 instance in the model will need to be recalculated.  This happens in order and when each one is finished cloudstep will tell you through its notification system.

You'll also notice a number next to the flag at the top navigation.  This number represents the number of changes that are still pending in the system.

You'll see several notifications appear in the bottom left hand corner of the screen explaining what's been updated.  These will automatically disappear after a few seconds.  To see the history of the last few hours of messages you can click on the Message menu (the little flag) in the top navigation to see the history.  The flag will show how many change are there to be processed.  There are a few different categories shown in this dropdown:

  • Completed.  The number of changes that have been successfully lodged and completed in the last 48 hours.
  • Waiting.  The number of changes that have not yet been actioned and are waiting in the queue.
  • Underway.  This is a measure of the number of changes that are currently being processed for your model.
  • Retrying.  Sometimes there is an issue in subspace.  If an entry needs to be re-calculated due to an issue thne it will show here as retrying.
  • Problems.  If there are fundamental problems with the element being changed and it cannot be recalculated when it will show here.

You can clock through this dropdown to see more detail about the activity cloudstep has been carrying out for you.