Note: The SUVM license is available from version 0.96.71.
In addition to the Standard license, IncrediBuild Linux offers you another type of license – Single-Use Virtual Machine (SUVM). This license is designed for Virtual Machines, which are launched for the sole purpose of providing additional cores to the execution of a build. After the build for which they were launched is completed, these machines are terminated.
If these VMs receive Standard licenses, after the machines are terminated, their licenses are no longer in use on the machine. Furthermore, their licenses cannot be used on another machine, since they are not automatically deallocated from the machine, and they are not released back to the license pool. Thus, Standard licenses that are allocated to VMs that are launched for one build only, become unavailable after a single use.
The SUVM licenses are designed for this kind of VMs. They are allocated by the Coordinator to these VMs once they are launched. When the build ends and the machines are terminated, the SUVM licenses are automatically deallocated and return back to the license pool. Then, the Coordinator can re-use them and allocate them to other machines.
In order to use the SUVM mechanism, the VMs that will receive SUVM licenses need to be created from a special VM image that was prepared in advance. This image should include a Helper and/or an Initiator Agent, which was installed on it using a specific IncrediBuild installation command. Once VMs will be launched using this image, they will automatically receive from the Coordinator SUVM licenses for their operation, according to the number of cores they report to have. When the VMs will complete the build execution and will be terminated, their SUVM licenses will be deallocated, and they will return to the license pool for re-use.
The deallocation of a SUVM license occurs automatically when the Coordinator no longer detects a communication with a VM, and the VM is considered to be offline. However, there may be cases when there are very short network disconnections, which may cause a VM to lose its connection with the Coordinator, although the VM is still up and running. To prevent the automatic license deallocation in such cases, IncrediBuild created a built-in timeout mechanism in the Coordinator. This default timeout instructs the Coordinator to wait 30 seconds, before it deallocates a license from a VM that is no longer connected.
Note: The running VMs that receive SUVM licenses, are registered in the Coordinator. After they are stopped or terminated and their licenses return to the license pool, they cannot be used again in IncrediBuild Environment. If you will try to re-use such a VM with IncrediBuild, the VM will appear on the Coordinator Monitor as an Expired machine.