7 Things to Know About Windows Azure Capacity
Windows Azure platform defines and enforces policies so that applications running on virtualized infrastructure will play nicely with each other. Awareness of these resource policies is important for assessing the capacity for successful operations and also for predicting the operational expenses for planning purposes.
Numbers courtesy of Hanu Kommalapati’s Blog and the Windows Azure Storage Abstractions and their Scalability Targets Blog entry
|Medium||2 x 1.6||3.5GB||490GB||200 Mbps|
|Large||4 x 1.6||7GB||1000GB||400 Mbps|
|XLarge||8 x 1.6||14Gb||2040GB||800 Mbps|
As with Network bandwidth CPU resource policies are implemented implicitly based on the instance type. The specific number of CPU cores that come with each role is shown below.
Each instance is provisioned with a pre-configured amount of memory. Role instances get their memory allocations based on the role type, from the remaining memory on the physical server, after the Root OS takes its share..
Each Azure Instance gets an allocation of volatile disk storage. Depending on whether your application is stateless or not you need consider two key considerations. If the applications store information on this storage, if the cleanOnRoleRecycle configuration setting is not set to “false”, the storage is recycled during a instance reboot. Also storage does not persist if the instance has to be relocated to another physical server. This can occur is there is a an underlying issue with the physical server as Azure will maintain the instances your requested automatically.
For more information about these numbers read Hanu Kommalapati’s Blog
Unlike the Instance Storage mentioned earlier Windows Azure Storage persists. Windows Azure Storage provides four object Abstractions for data storage.
When creating a storage account you can specify a location to place your storage account in. The six locations we currently offer are:
As a best practice, you should choose the same location for your storage account and your instances.
A singe Storage Account can be up to 100TB in size. This is a hard limit. A single subscription can have 5 storage accounts. This limit is not fixed and more accounts can be requested via customer support.