If there is no resource the monitoring utility will not show information, due to there is no row in the database for the steps in which there is no resource. It will return an empty array.

Example:¶

If the number of running VMs in the cloud is 10 and you delete all of them, the Sunstone monitoring graphic will not be updated and will show the last timestamp information that shows 10 VMs running (the timestamp will show that is an old value). When an instance is started again the graphic will show a line from 10 to 1 without showing the timestamps in which the number of VMs was 0.

Solution:¶

2 new tables and their Sequel models must be created:

• VM_TIMESTAMPS
• HOST_TIMESTAMPS
  Containing as many rows as the WINDOW_SIZE specifies. This way all the timestamps will be registered.

The VM_SAMPLES and HOST_SAMPLES must be modified, adding a new foreign key for the timestamp column.

To keep as many rows as the WINDOW_SIZE specifies each time a flush is called the Timestamp class must delete the old rows deleting as well the samples associated.