Update Dockerfile to build Megablocks (#2042)

Dockerfile

@@ -41,6 +41,14 @@ ENV NVCC_THREADS=$nvcc_threads
 
 RUN python3 setup.py build_ext --inplace
 
+# Build the megablocks library as wheel because it doesn't publish pre-built wheels.
+# https://github.com/stanford-futuredata/megablocks/commit/5897cd6f254b7b3edf7a708a3a3314ecb54b6f78
+RUN apt-get install -y git && \
+    git clone https://github.com/stanford-futuredata/megablocks.git && \
+    cd megablocks && \
+    git checkout 5897cd6f254b7b3edf7a708a3a3314ecb54b6f78 && \
+    MAX_JOBS=8 NVCC_THREADS=8 python3 setup.py bdist_wheel
+
 # image to run unit testing suite
 FROM dev AS test
 
@@ -73,12 +81,16 @@ ENTRYPOINT ["python3", "-m", "vllm.entrypoints.api_server"]
 
 # openai api server alternative
 FROM vllm-base AS vllm-openai
-# install additional dependencies for openai api server, and mixtral
+# install additional dependencies for openai api server
 RUN --mount=type=cache,target=/root/.cache/pip \
-    pip install accelerate megablocks
+    pip install accelerate
 
-COPY --from=build /workspace/vllm/*.so /workspace/vllm/
 COPY vllm vllm
+COPY --from=build /workspace/vllm/*.so /workspace/vllm/
+COPY --from=build /workspace/megablocks/dist/*.whl /tmp/
+RUN --mount=type=cache,target=/root/.cache/pip \
+    pip install /tmp/megablocks-0.5.0-cp310-cp310-linux_x86_64.whl && \
+    rm /tmp/megablocks-0.5.0-cp310-cp310-linux_x86_64.whl
 
 ENTRYPOINT ["python3", "-m", "vllm.entrypoints.openai.api_server"]