Automatic scaling of websites, cloud services and virtual machines
Thanks to the autoscaling feature, a Windows Azure user can set rules and conditions to automatically increase or decrease allocated computing capacity based on the current application load.
The Windows Azure platform will grow or shrink instances of websites, cloud services, or virtual machines on its own, depending on the given conditions and the current load on the cloud application. Thus, users of the Windows Azure cloud platform can now use autoscaling to quickly provision cloud capacity as workloads increase and save money when workloads fall.
Scaling cloud websites
Automatic scaling of Windows Azure Web Sites cloud websites is available based on the CPU load parameter. A Windows Azure Web Sites user must select the size of each website instance: Small, Medium, and Large for scaling purposes. The sizes differ in the number of CPU cores and the amount of available memory.
Using the administration panel, the user can set scaling goals - the minimum and maximum CPU load limits at which a change in the configuration occurs, and website instances are allocated or deleted.
Scaling cloud services based on CPU
Windows Azure cloud services can automatically scale based on CPU utilization in the same way that websites can. However, additional features and scaling options are available for cloud services.
In the administration panel of cloud services in Windows Azure, the user has a scaling forecast, which informs about the need to quickly scale for the cloud service.
Cloud services, unlike websites, can scale to multiple instances at once. A special option is available in the administration panel that allows you to specify the number of instances to scale up and down the service.
In addition, to set up the automatic scaling of the cloud service, you must specify the waiting period after each rescaling, but if something does not work out, be sure to contact https://unicsoft.com/cloud-consulting/ . The user can specify the amount of time to wait in minutes before the next zoom in or out. This makes sense for scenarios where new role instances are delayed and are not immediately ready to offload the load on the service.
Scaling cloud services based on queued messages
The biggest difference between the autoscaling feature of cloud services and websites is the support for scaling based on the number of messages in the queue.
This autoscaling mode allows you to scale up or down the number of cloud service instances based on the current number of messages in the Windows Azure storage message queue. With this feature, Windows Azure users can create message queuing services that automatically scale when the number of messages in the queue grows or drops significantly.
In the administration panel, the user can specify the storage account that contains the message queue and the name of the queue itself, based on the number of messages in which the service needs to be scaled. In addition, the user must specify the number of messages in the queue at which Windows Azure will automatically increase or decrease the number of service instances.
Scaling virtual machines
Virtual machines in Windows Azure are autoscaled based on a machine-mapped cloud service.
The virtual machine instances participating in scaling must be consolidated into a single availability set. When zoomed in, virtual machines will power on, and when zoomed out, they stop.