Add demo about Click-Through-Rate distributed training with PaddlePad…

[sivanzcw]

Add demo about distributed training with PaddlePaddle on Volcano, source demo taken from https://github.com/PaddlePaddle/edl/tree/develop/example/ctr

[k82cn]

let's move this image to volcanosh

[sivanzcw]

Already replaced with volcanosh image

[k82cn]

/approve

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[hzxuzhonghu]

I am not familiar with paddlepaddle, but what's this?

[sivanzcw]

PADDLE INIT NICS is used to pass the nics parameter to specify the network card in the paddle pserver or paddle train command here

start_pserver() {
   stdbuf -oL paddle pserver \
     --use_gpu=0 \
     --port=$PADDLE_INIT_PORT \
     --ports_num=$PADDLE_INIT_PORTS_NUM \
     --ports_num_for_sparse=$PADDLE_INIT_PORTS_NUM_FOR_SPARSE \
     --nics=$PADDLE_INIT_NICS \
     --comment=paddle_process_k8s \
     --num_gradient_servers=$PADDLE_INIT_NUM_GRADIENT_SERVERS
}

The default value is taken from the relevant configuration in the PaddlePaddle EDL demo here

[hzxuzhonghu]

What if eth2 not exist in a container?

[sivanzcw]

After testing, for this demo, setting a non-existent NIC for PaddlePaddle does not affect the training process. Based on the original Baidu demo, this parameter was removed. During the implementation of the demo, each pod filters out the server and trainer components through the preset PServer pod lable and Trainer pod lable, thus obtaining the ip list of the server and trainer components. When obtaining the server ip list, the system assign a port to the server at the same time. After the server gets the assigned port, it starts listening to the corresponding port and provides services. Finally, each server or trainer component in the computing cluster knows the detailed communication address of other components under the cluster, so the components can communicate directly without using the network card configuration.

[hzxuzhonghu]

/lgtm