16.2.3. Global Task Scheduling

Through the development of big.LITTLE technology, ARM has evolved the software models starting with various migration models through to Global Task Scheduling (GTS) that forms the basis for all future development in big.LITTLE technology. The ARM implementation of GTS is called big.LITTLE Multiprocessing (MP).

Figure 16.3. Global Task Scheduling

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In this model the operating system task scheduler is aware of the differences in compute capacity between big and LITTLE cores. Using statistical data, the scheduler tracks the performance requirement for each individual software thread, and uses that information to decide which type of core to use for each. This model can work on a big.LITTLE system with any number of cores in any cluster. This is shown in Figure 16.3. This approach has a number of advantages over the migration models, such as:

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