Cloud Instances (Single / Multi-Instance)
A “cloud instance” refers to a virtual server instance from a public or private cloud network. In cloud instance computing, single hardware is implemented into software and run on top of multiple computers. Cloud instance computing is highly dynamic, enabling users not to worry about how many servers can fit on a single hardware application without causing major slowdowns during peak hours. If performance maxes out, you can simply add more computers. Resources can be freely allocated to and from other computers by the software, enabling maximum utilization and helping to prevent crashes. If the server grows beyond the limits of a single machine, cloud instance computing allows the cloud software to be easily expanded to span multiple machines, whether temporarily or permanently. Cloud instance computing also reduces the downtime associated with servicing hardware. A server in the cloud can be easily moved from one physical machine to another without going down. The abstraction associated with the cloud allows hardware to seamlessly transfer all data from one point to another without the end-user having any idea that it happened. In sum, cloud instance computing is highly dynamic, can reassign resources as needed, and allows for the movement of servers as they run in the cloud.
The Single Instance Cloud vs. the Multi Instance Cloud
What’s the difference between a single instance cloud and a multi instance cloud? Think of the cloud as a single entity comprising the data shared across multiple machines. The cloud juggles resources between the different machines while communicating with remote machines. In a multi-instance cloud, entirely separate instances (that is, separate copies of defined data items) are run parallel to one another.
Although the single-instance cloud shouldn’t get bogged down while servicing requests as long as the hardware has adequate resources and speed, additional cloud instances in the multi instance cloud can help to speed up the overhead associated with interfacing the remote machines with which the cloud communicates.
Multi-Tenancy vs. Multi-Instance
If you are unfamiliar with the terms, multi tenancy commingles the data and processing for multiple clients in a single application instance. By contrast, a multi instance architecture uses one application instance per client. With the multi-instance model, organizations must devote their time to efficiently creating and managing multiple application instances, whereas organizations that opt for multi-tenancy often need to invest in application code to prevent the exposure of data from one client to another. However, some providers, such as Apprenda, offer single-instance multi tenancy architecture as a standard platform service, guaranteeing security, streamlining the development cycle, and ensuring the efficient and high-quality utilization of resources.