Disable cudnn by default for #127. Add warning.

training/main.lua

@@ -17,6 +17,11 @@ if opt.cuda then
    cutorch.setDevice(1)
 end
 
+if opt.cudnn then
+   print("\nThere is a known issue with cudnn training! See:")
+   print("  https://github.com/cmusatyalab/openface/issues/127\n\n")
+end
+
 os.execute('mkdir -p ' .. opt.save)
 torch.save(paths.concat(opt.save, 'opts.t7'), opt, 'ascii')
 print('Saving everything to: ' .. opt.save)

training/opts.lua

@@ -28,7 +28,7 @@ function M.parse(arg)
               'Home of dataset. Split into "train" and "val" directories that separate images by class.')
    cmd:option('-manualSeed', 2, 'Manually set RNG seed')
    cmd:option('-cuda', true, 'Use cuda.')
-   cmd:option('-cudnn', true, 'Convert the model to cudnn.')
+   cmd:option('-cudnn', false, 'Convert the model to cudnn.')
 
    ------------- Data options ------------------------
    cmd:option('-nDonkeys', 2, 'number of donkeys to initialize (data loading threads)')