data-science-ipython-notebooks/deep-learning/tensor-flow-examples/multigpu_basics.py
2015-12-28 07:49:25 -05:00

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Python

#Multi GPU Basic example
'''
This tutorial requires your machine to have 2 GPUs
"/cpu:0": The CPU of your machine.
"/gpu:0": The first GPU of your machine
"/gpu:1": The second GPU of your machine
'''
import numpy as np
import tensorflow as tf
import datetime
#Processing Units logs
log_device_placement = True
#num of multiplications to perform
n = 10
'''
Example: compute A^n + B^n on 2 GPUs
Results on 8 cores with 2 GTX-980:
* Single GPU computation time: 0:00:11.277449
* Multi GPU computation time: 0:00:07.131701
'''
#Create random large matrix
A = np.random.rand(1e4, 1e4).astype('float32')
B = np.random.rand(1e4, 1e4).astype('float32')
# Creates a graph to store results
c1 = []
c2 = []
def matpow(M, n):
if n < 1: #Abstract cases where n < 1
return M
else:
return tf.matmul(M, matpow(M, n-1))
'''
Single GPU computing
'''
with tf.device('/gpu:0'):
a = tf.constant(A)
b = tf.constant(B)
#compute A^n and B^n and store results in c1
c1.append(matpow(a, n))
c1.append(matpow(b, n))
with tf.device('/cpu:0'):
sum = tf.add_n(c1) #Addition of all elements in c1, i.e. A^n + B^n
t1_1 = datetime.datetime.now()
with tf.Session(config=tf.ConfigProto(log_device_placement=log_device_placement)) as sess:
# Runs the op.
sess.run(sum)
t2_1 = datetime.datetime.now()
'''
Multi GPU computing
'''
#GPU:0 computes A^n
with tf.device('/gpu:0'):
#compute A^n and store result in c2
a = tf.constant(A)
c2.append(matpow(a, n))
#GPU:1 computes B^n
with tf.device('/gpu:1'):
#compute B^n and store result in c2
b = tf.constant(B)
c2.append(matpow(b, n))
with tf.device('/cpu:0'):
sum = tf.add_n(c2) #Addition of all elements in c2, i.e. A^n + B^n
t1_2 = datetime.datetime.now()
with tf.Session(config=tf.ConfigProto(log_device_placement=log_device_placement)) as sess:
# Runs the op.
sess.run(sum)
t2_2 = datetime.datetime.now()
print "Single GPU computation time: " + str(t2_1-t1_1)
print "Multi GPU computation time: " + str(t2_2-t1_2)