OpenMP Offloading: Data Transfer with map Clause¶

1. What is the primary function of the map(to:) clause in OpenMP Offloading?

• A. Allocates memory on the device without initializing it.
• B. Copies data from the device back to the host after execution.
• C. Transfers the original variable from the host to the device at the start of the region.
• D. Synchronizes data between the host and device at any point.

Types of map Clauses¶

2. Which map clause should be used if the variable is updated on the device and needs to be available on the host after computation?

• A. map(to:)
• B. map(from:)
• C. map(alloc:)
• D. map(delete:)

3. True or False: The map(alloc:) clause allocates memory for a variable on the device without copying any data from the host.

Practical Data Management with target data and target update¶

4. Which OpenMP construct is used to keep data on the device across multiple target regions without remapping it each time?

• A. target update
• B. target data
• C. target teams
• D. parallel

5. True or False: The target update from(list) clause is used to transfer data from the host to the device within a target data region.

target enter data and target exit data¶

6. Which construct should be used to allocate device memory without immediately executing code?

• A. target
• B. target data
• C. target enter data
• D. target exit data

7. In the following code, what will the target exit data construct do for array C?

#pragma omp target exit data map(from: C[0:n]) map(delete: A[0:n], B[0:n])

• A. Transfer C from the device to the host and keep A and B on the device.
• B. Transfer C from the device to the host and delete A and B on the device.
• C. Keep C on the device but transfer A and B to the host.
• D. Delete C, A, and B from the device without transferring data to the host.

8. True or False: The map(tofrom:) clause ensures that the variable is both copied to the device at the start of the region and copied back to the host after the region ends.

9. Which OpenMP construct allows you to synchronize data from the device to the host during the execution of a target data region?

• A. target update
• B. map(from:)
• C. target enter data
• D. target exit data

10. In OpenMP Offloading, what does the map(delete:) clause do?

• A. Deletes the data from the device without copying it back to the host.
• B. Deletes the data from the device and copies it back to the host.
• C. Allocates memory on the device but does not initialize it.
• D. Copies the data to the device without copying it back.