+ 'persistent_memory' parameter added to gpu_conf, basically what it does is tries to allocate some memory that is normally not available to the GPU. It can increase hashrate in some ocassions, by finding the right intensity and threads setup, but also it can make the gpu crash, so it's up to you to experiment 
thanks for update is this correct usage?
{ "id" : 0, "intensity" : 112, "worksize" : 16, "threads" : 2, "persistent_memory" : true},
didn't crash, but no hashrate changes too
PS you broke JSON API. it shows "cryptonight_type": "\u0000\u0000\u0000\u0000\u0000\u0000\u0000\u0000" instead of normalv7