Answers for "how to check tensorflow use gpu"

check if tensorflow gpu is installed

import tensorflow as tf
print(tf.test.gpu_device_name())

tensorflow gpu test

# As it's written in Tensorflow documentatoin: 

import tensorflow as tf
print("Num GPUs Available: ", len(tf.config.experimental.list_physical_devices('GPU')))

check gpu in tensorflow

# For tensorflow 2:
print("Num GPUs Available: ", len(tf.config.list_physical_devices('GPU')))

# For tensorflow 1:
sess = tf.Session(config=tf.ConfigProto(log_device_placement=True))