System-Level Design:Allocating and Scheduling Storage Modules

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Allocating and Scheduling Storage Modules

In digital systems, all data require some form of temporary or permanent storage. If the storage is shared by several data sets, the use of the storage by each data set must be scheduled. The importance of this task in system design has been overlooked in the past, but has now become an important system-level task. Modern digital systems usually contain some multimedia tasks and data. The storage requirements for multimedia tasks sometimes result in systems where processing costs are dwarfed by storage costs, particularly caching costs. For such systems, storage must be scheduled and allocated either during or after task scheduling and allocation. If storage is scheduled and allocated concurrently with task scheduling and allocation, the total system costs are easier to determine and functional module sharing can be increased if necessary to control total costs. Alternatively, if storage allocation and scheduling are performed after task scheduling and allocation, then both programs are simpler, but the result may not be as close to optimal.

Techniques similar to those used for task scheduling and allocation can be used for storage scheduling and allocation.

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