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Setting Physical and Logical Service Locks on Squadrons-S Disclosure Number: IPCOM000199140D
Publication Date: 2010-Aug-26
Document File: 2 page(s) / 22K

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The Prior Art Database


A software lock system is designed that resolves potential conflicting parallel service tasks running on DS8000 HMC. The design organizes all logical and physical entities of DS8000 system that might be involved in service actions into a network of service objects. The service objects may have ownership relationship to each other or an association to each other. Each service object has a lock. Depending on the position of a service object in the network, its lock may have different implications to locks of other service objects. In addition, lock has the property of exclusive or non-exclusive which results in different behavior for the process that obtains or holds the lock. This lock system has resulted in more efficient maintenance activities by allowing parallel service actions when possible.

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Setting Physical and Logical Service Locks on Squadrons -S


DS8000 HMC is the management focus point for all machine service actions. The service actions include install, MES, repair, code update, debug data collection and so on. The HMC user interface allows the user start parallel processes, i.e. begin another task while some other tasks are still running. Moreover, the HMC can be accessed over network. Hence, it is possible for multiple users to log in the same HMC performing tasks that may be in conflict to one another. In addition, some service task, such as HMC code update, requires HMC reboot at the end, which will kill all processes that are running at the time. It is clear that a system that will coordinate this multi-user and multi-tasking environment is necessary. It is desirable to maintain the multi-user and multi-tasking environment to a maximum extent if the underlying tasks are not in conflict to each other.


A software lock system is designed and implemented that resolves potential conflicting parallel service tasks while allow multi-tasking of tasks that do not interfere with each other.

The foundation of this lock system is the service object network hierarchy. As shown in Figure 1, all service related entities in DS8000, whether it's physical or logical, are abstracted into service objects and are organized into a hierarchical structure. One of the common properties of the service objects is that they all own a lock which can be set or reset.

The service objects have related by one of two types of relationships, ownership and association. These relationships are depicted in Figure 1 by arrows and dash lines respectively. Figure 1 is only a concept diagram. It does not contain a complete list of all service objects and not all relationships among the objects in the figure are shown.

The ownership relationship is simple and straightforward. The lock of a service object will automatically set locks all service objects that it owns. The association relationship may be handled in a few methods. One of them is for hardware redundancy. For example, if a hardware component A is taking offline for service, the lock of its service object is set. The hardware component A' that services as redundant part of A does not have an ownership relationship with
A. A and A' typically do not belong to same parent service object until the very top level. However, it should not be allowed to service A' until service on A is completed. This requirement can be handled by associ...