The data set is the primary mechanism for optimizing an ALF application on a hybrid system. Using the data set improves ALF application performance on the hybrid environment significantly. For an overview about data sets, see Data set.
The ALF on Hybrid implementation uses the data set to speed up data read/write access time by migrating the data set closer to the accelerators. That is, when the task is ready and is scheduled for execution on a specific PowerPC® Processing Element (PPE), the associated data set is transferred from the Hybrid host to the PPE. This makes the data set available for the accelerator’s data access. All read-only and read-write buffers are transferred then. Similarly, when you issue the alf_task_wait function, and the task completes, the data set is transferred from the PPE to the Hybrid host. This makes the data set available for the host’s data access. All the write-only and read-write buffers are transferred then.
Refer to Data set example for an example of how to use data sets.