Tensor flow toggle between CPU/GPU

Question

Having installed tensorflow GPU (running on a measly NVIDIA GeForce 950), I would like to compare performance with the CPU.

I am running the tensorFlow MNIST tutorial c

Answer 1

# Check if the server/ instance is having GPU/ CPU from python code
import sys
import tensorflow as tf
from tensorflow.python.client import device_lib

# device_lib.list_local_devices()     ## this command list all the processing device GPU and CPU


device_name = [x.name for x in device_lib.list_local_devices() if x.device_type == 'GPU']
if device_name[0] == "/device:GPU:0":
    device_name = "/gpu:0"
    #print('GPU')
else:
    #print('CPU')
    device_name = "/cpu:0"

with tf.device(device_name):
    a = tf.constant([1.0, 2.0, 3.0, 4.0, 5.0, 6.0], shape=[2, 3], name='a')
    b = tf.constant([1.0, 2.0, 3.0, 4.0, 5.0, 6.0], shape=[3, 2], name='b')
    c = tf.matmul(a, b)
with tf.Session() as sess:
    print (sess.run(c))