This folder contains iOS RPC app that allows us to launch an rpc server on a iOS device(e.g. ipython) and connect to it through python script and do testing on the python side as normal TVM RPC. You will need XCode and an iOS device to use this.
Start the RPC proxy by running in a terminal:
python -m tvm.exec.rpc_proxy
On success, you should see something like this:
INFO:root:RPCProxy: client port bind to 0.0.0.0:9090 INFO:root:RPCProxy: Websock port bind to 8888
IP-address of this machine will be used to initialize TVM_IOS_RPC_PROXY_HOST environment variable (see below).
Before start, please run init_proj.py to update XCode developer metadata. After this step, open tvmrpc.xcodeproj by using XCode, build the App and install the App on the phone. Usually, we do not use the iOS App directly.
To test an App, you can fill Address field with IP-address of RPC proxy (see above), and press Connect to Proxy.
On success, “Disconnected” will change to “Connected”. On RPC proxy side you can see the next message in a log:
INFO:root:Handler ready TCPSocketProxy:<iPhone IP address>:server:iphone
Now App can be closed by pressing the home button (or even removed from a device).
Due to security restriction of iOS10. We cannot upload dynamic libraries to the App and load it from sandbox. Instead, we need to build a list of libraries, pack them into the app bundle, launch the RPC server and connect to test the bundled libraries. We use xcodebuild test to automate this process.
The test script tests/ios_rpc_test.py is a good template for the workflow. With this script, we don't need to manually operate the iOS App, this script will build the app, run it and collect the results automatically.
To run the script, you need to configure the following environment variables
TVM_IOS_CODESIGN The signature you use to codesign the app and libraries (e.g. iPhone Developer: Name (XXXX))TVM_IOS_RPC_ROOT The root directory of the iOS rpc projectTVM_IOS_RPC_PROXY_HOST The RPC proxy address (see above)TVM_IOS_RPC_DESTINATION The Xcode target device (e.g. platform=iOS,id=xxxx)See instructions of how to find UUID of the iOS device:
Let us explain how it works, the project look for rpc_config.txt file in the project root folder. The rpc_config.txt file should be in the following format:
<url> <port> <key> [path to dylib1] [path to dylib2] ...
The build script will copy all the dynamic libraries into bundle tvmrpc.app/Frameworks/tvm, which you will be able to load via RPC using remote.load_module. It will also create an tvmrpc.app/Frameworks/tvm/rpc_config.txt containing the first line.
When we run the testcase, the testcase read the configuration from tvmrpc.app/Frameworks/tvm/rpc_config.txt and connect to the specified RPC proxy, start serving loop.
So if we want to start the RPC from XCode IDE, simply manually modify rpc_config.txt file and click test. Then connect to the proxy via the python script.
We can also use the RPC App directly, by typing in the address and press connect to connect to the proxy. However, the restriction is we can only load the modules that are bundled to the App.