your batch tries to augment all of your images at once and when you add *5, it is getting too big. I think augmentation is happening in CPU And your 16GB of RAM can’t handle it.
look at https://keras.io/preprocessing/image/
try to do it manually in smaller batches that your machine can handle
for e in range(epochs):
print('Epoch', e)
batches = 0
for x_batch, y_batch in datagen.flow(x_train, y_train, batch_size=32):
model.fit(x_batch, y_batch)
batches += 1
if batches >= len(x_train) / 32:
# we need to break the loop by hand because
# the generator loops indefinitely
break
I put all the data in an variable first and then use this, but you should be able to read the batches from directory