add cache to speed up docker building (#2344)

docker/Dockerfile

@@ -21,10 +21,6 @@ RUN apt-get update -y && apt-get install -y software-properties-common wget vim
 
 ENV PATH=/opt/py3/bin:$PATH
 
-RUN python3 -m pip install --no-cache-dir --upgrade pip setuptools==69.5.1 &&\
-    python3 -m pip install --no-cache-dir torch==${TORCH_VERSION} torchvision==${TORCHVISION_VERSION} --index-url https://download.pytorch.org/whl/${CUDA_VERSION_SHORT} &&\
-    python3 -m pip install --no-cache-dir cmake packaging wheel
-
 # install openmpi
 RUN wget https://download.open-mpi.org/release/open-mpi/v4.1/openmpi-4.1.5.tar.gz &&\
     tar xf openmpi-4.1.5.tar.gz && cd openmpi-4.1.5 && ./configure --prefix=/usr/local/openmpi &&\
@@ -33,22 +29,25 @@ RUN wget https://download.open-mpi.org/release/open-mpi/v4.1/openmpi-4.1.5.tar.g
 ENV PATH=$PATH:/usr/local/openmpi/bin
 ENV LD_LIBRARY_PATH=$LD_LIBRARY_PATH:/usr/local/openmpi/lib
 
+RUN --mount=type=cache,target=/root/.cache/pip python3 -m pip install --upgrade pip setuptools==69.5.1 &&\
+    python3 -m pip install torch==${TORCH_VERSION} torchvision==${TORCHVISION_VERSION} --index-url https://download.pytorch.org/whl/${CUDA_VERSION_SHORT} &&\
+    python3 -m pip install cmake packaging wheel
+
 ENV NCCL_LAUNCH_MODE=GROUP
 
 # Should be in the lmdeploy root directory when building docker image
 COPY . /opt/lmdeploy
 
 WORKDIR /opt/lmdeploy
 
-RUN cd /opt/lmdeploy &&\
-    python3 -m pip install --no-cache-dir -r requirements.txt &&\
+RUN --mount=type=cache,target=/root/.cache/pip cd /opt/lmdeploy &&\
+    python3 -m pip install -r requirements.txt &&\
     mkdir -p build && cd build &&\
     sh ../generate.sh &&\
     ninja -j$(nproc) && ninja install &&\
     cd .. &&\
     python3 -m pip install -e . &&\
-    rm -rf build  &&\
-    rm -rf ~/.cache/*
+    rm -rf build
 
 ENV LD_LIBRARY_PATH=/opt/lmdeploy/install/lib:$LD_LIBRARY_PATH
 ENV PATH=/opt/lmdeploy/install/bin:$PATH