Getting Unknown pooling method error each time I try to use STOCHASTIC for pooling method

[Hossein Hasanpour]

I am trying to use STOCHASTIC pooling in caffe, but each time I try to use it it crashes the caffe with this error : 

F0510 10:58:23.023799 12080 cudnn.hpp:125] Unknown pooling method.
*** Check failure stack trace: ***

and this is my pooling layer definition : 

layer {
  name: "pool2_1"
  type: "Pooling"
  bottom: "relu2_1"
  top: "pool2_1"
  pooling_param {
    pool: STOCHASTIC
    kernel_size: 2
    stride: 2
  }
}

I tired using the integer value 2 instead of the stochastic string, but nothing nothing changes! 

the Max and AVE are fine though! 

[Hossein Hasanpour]

I found the reason and solution to the problem : https://github.com/BVLC/caffe/issues/4123 

Actually STOCHASTIC needs to be used with CAFFE engine. it is not implemented in cudnn it seems. 

I witnessed something strange thought, using the STOCHASTIC pooling, the accuracy decreased really bad! e.g from 99% accuracy it decreased  to 43%. 

Is this expected ? or is it a bug? 
I thought STOCHASTIC pooling was supposed to enhance the performance and accuracy of the network! not destroying it!