Clink

Clink is a library that provides infrastructure to do the following:

Defines C++ functions that can be parallelized by TFRT threadpool.
Executes a graph (in the MLIR format) of these C++ functions in parallel.
Makes C++ functions executable as Java functions using JNA.

Furthermore, Clink provides an off-the-shelf library of reusable Feature Processing functions that can be executed as Java and C++ functions.

Clink is useful in the scenario where users want to do online feature processing with low latency (in sub-millisecond) in C++, apply the same logic to do offline feature processing in Java, and implement this logic only once (in C++).

Getting Started

Prerequisites

Clink uses TFRT as the underlying execution engine and therefore follows TFRT's Operation System and installation requirements.

Here are the prerequisites to build and install Clink:

Ubuntu 16.04
Bazel 4.0.0
Clang 11.1.0
libstdc++8 or greater
openjdk-8

Please checkout the TFRT README for more detailed instructions to install, configure and verify Bazel, Clang and libstdc++8.

Build docker image with the libraries required by Clink

Build docker image based on Ubuntu 16.04

Use the following command to build the docker image.

docker build -t ubuntu:16.04_clink -f docker/Dockerfile_ubuntu_1604 .

The pre-built docker image can be pulled from Docker Hub using the following command.

docker pull docker.io/flinkextended/clink:ubuntu16.04

Build docker image based on CentOS 7.7

Use the following command to build the docker image. Note that the CentOS Dockerfile needs to compile Clang 11 from source code. This could take a few hours depending on your machine.

docker build -t centos:centos7.7.1908_clink -f docker/Dockerfile_centos_77 .

The pre-built docker image can be pulled from Docker Hub using the following command.

docker pull docker.io/flinkextended/clink:centos7.7.1908

Setup Clink repo before building Clink

git submodule update --init --recursive

Build & Test all Targets

Users can run the following command to build all targets and to run all tests.

bazel test $(bazel query //...)

Execute Clink C++ functions in parallel in C++

bazel run //:executor -- `pwd`/mlir_test/executor/basic.mlir --work_queue_type=mstd --host_allocator_type=malloc

Format codes using clang-format and diffplug-spotless

Clink uses ClangFormat to format C++ code.

find . \( -name "*.cc" -or -name "*.h" \) -not -path "./tfrt/*" -exec clang-format -i -style=llvm {} \;

And it uses diffplug/spotless to format java code.

mvn -f java-lib spotless:apply

View & Edit Java Code with IDE

Clink provides maven configuration that allows users to view or edit java code with IDEs like IntelliJ IDEA. Before IDEs can correctly compile java project, users need to run the following commands after setting up Clink repo and build Clink.

bazel build //:clink_java_proto
cp bazel-bin/libclink_proto-speed.jar java-lib/lib/

Then users can open java-lib directory with their IDEs.

shouweikun/clink