update horovod for mxnet

Author: hephaex

commons/Dockerfile.base.py38-cuda11.2

@@ -427,7 +427,7 @@ RUN python3 -m pip install --extra-index-url \
 # Install Horovod, temporarily using CUDA stubs
 RUN ldconfig /usr/local/cuda/targets/x86_64-linux/lib/stubs && \
     HOROVOD_GPU_ALLREDUCE=NCCL HOROVOD_GPU_BROADCAST=NCCL HOROVOD_NCCL_LINK=SHARED \
-    HOROVOD_WITH_TENSORFLOW=1 HOROVOD_WITH_PYTORCH=1 HOROVOD_WITHOUT_MXNET=1\
+    HOROVOD_WITH_TENSORFLOW=1 HOROVOD_WITH_PYTORCH=1 HOROVOD_WITH_MXNET=1\
     HOROVOD_GPU=CUDA \
     python3 -m pip install --no-cache-dir horovod==0.23.0 && \
     ldconfig
@@ -456,10 +456,6 @@ COPY policy.yml /etc/backend.ai/jail/policy.yml
 COPY ./service-defs /etc/backend.ai/service-defs
 COPY ./runner-scripts/bootstrap.sh runner-scripts/setup_multinode.py /opt/container/
 
-# Install ipython kernelspec
-RUN python3 -m ipykernel install --display-name "TensorFlow 2.7 on Python 3.8 (CUDA 11.2)" && \
-    cat /usr/local/share/jupyter/kernels/python3/kernel.json
-
 # Clean up
 RUN apt autoclean && \
     ln -s /usr/local/cuda-11.2/targets/x86_64-linux/lib/libcusolver.so.11 /usr/local/cuda-11.2/targets/x86_64-linux/lib/libcusolver.so.10 && \