2.0 Compatible Answer: While above mentioned answer explain in detail on how to use GPU on Keras Model, I want to explain how it can be done for Tensorflow Version 2.0.
To know how many GPUs are available, we can use the below code:
print("Num GPUs Available: ", len(tf.config.experimental.list_physical_devices('GPU')))
To find out which devices your operations and tensors are assigned to,
put tf.debugging.set_log_device_placement(True) as the first statement of your program.
Enabling device placement logging causes any Tensor allocations or operations to be printed. For example, running the below code:
tf.debugging.set_log_device_placement(True)
# Create some tensors
a = tf.constant([[1.0, 2.0, 3.0], [4.0, 5.0, 6.0]])
b = tf.constant([[1.0, 2.0], [3.0, 4.0], [5.0, 6.0]])
c = tf.matmul(a, b)
print(c)
gives the Output shown below:
Executing op MatMul in device /job:localhost/replica:0/task:0/device:GPU:0 tf.Tensor( [[22. 28.] [49. 64.]], shape=(2, 2), dtype=float32)
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