Add dynamic batcher node

CMakeLists.txt

@@ -122,7 +122,7 @@ enable_language(CUDA)
 set(MRC_ROOT_DIR ${CMAKE_CURRENT_SOURCE_DIR})
 
 # Set a default build type if none was specified
-rapids_cmake_build_type(Release)
+rapids_cmake_build_type(Debug)
 
 set(CMAKE_CXX_STANDARD 20)
 set(CMAKE_CXX_STANDARD_REQUIRED ON)

cpp/mrc/include/mrc/node/operators/dynamic_batcher.hpp

@@ -0,0 +1,132 @@
+/*
+ * SPDX-FileCopyrightText: Copyright (c) 2021-2023, NVIDIA CORPORATION &
+ * AFFILIATES. All rights reserved. SPDX-License-Identifier: Apache-2.0
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#pragma once
+
+#include "mrc/channel/buffered_channel.hpp"
+#include "mrc/channel/channel.hpp"
+#include "mrc/constants.hpp"
+#include "mrc/core/utils.hpp"
+#include "mrc/core/watcher.hpp"
+#include "mrc/exceptions/runtime_error.hpp"
+#include "mrc/node/rx_epilogue_tap.hpp"
+#include "mrc/node/rx_prologue_tap.hpp"
+#include "mrc/node/rx_sink_base.hpp"
+#include "mrc/node/rx_source_base.hpp"
+#include "mrc/node/rx_subscribable.hpp"
+#include "mrc/runnable/runnable.hpp"
+#include "mrc/utils/type_utils.hpp"
+#include "rxcpp/operators/rx-observe_on.hpp"
+
+#include <glog/logging.h>
+#include <rxcpp/operators/rx-buffer_time_count.hpp>
+#include <rxcpp/rx.hpp>
+
+#include <exception>
+#include <memory>
+#include <mutex>
+
+namespace mrc::node {
+template <typename T, typename ContextT>
+class DynamicBatcher : public mrc::node::WritableProvider<T>,
+                       public mrc::node::ReadableAcceptor<T>,
+                       public mrc::node::SinkChannelOwner<T>,
+                       public mrc::node::WritableAcceptor<std::vector<T>>,
+                       public mrc::node::ReadableProvider<std::vector<T>>,
+                       public mrc::node::SourceChannelOwner<std::vector<T>>,
+                       public mrc::runnable::RunnableWithContext<ContextT> {
+  using state_t = mrc::runnable::Runnable::State;
+  using input_t = T;
+  using output_t = std::vector<T>;
+
+public:
+  DynamicBatcher(size_t max_count, std::chrono::milliseconds duration)
+      : m_max_count(max_count), m_duration(duration) {
+    // Set the default channel
+    mrc::node::SinkChannelOwner<input_t>::set_channel(
+        std::make_unique<mrc::channel::BufferedChannel<input_t>>());
+    mrc::node::SourceChannelOwner<output_t>::set_channel(
+        std::make_unique<mrc::channel::BufferedChannel<output_t>>());
+  }
+  ~DynamicBatcher() override = default;
+
+private:
+  /**
+   * @brief Runnable's entrypoint.
+   */
+  void run(mrc::runnable::Context &ctx) override {
+    // T input_data;
+    // auto status = this->get_readable_edge()->await_read(input_data);
+
+    // Create an observable from the input channel
+    auto input_observable =
+        rxcpp::observable<>::create<T>([this](rxcpp::subscriber<T> s) {
+          T input_data;
+          while (this->get_readable_edge()->await_read(input_data) ==
+                 mrc::channel::Status::success) {
+            s.on_next(input_data);
+          }
+          s.on_completed();
+        });
+
+    // DVLOG(1) << "DynamicBatcher: m_duration: " << m_duration.count() << std::endl;
+
+    // Buffer the items from the input observable
+    auto buffered_observable = input_observable.buffer_with_time_or_count(
+        m_duration, m_max_count, rxcpp::observe_on_event_loop());
+
+    // Subscribe to the buffered observable
+    buffered_observable.subscribe(
+        [this](const std::vector<T> &buffer) {
+          this->get_writable_edge()->await_write(buffer);
+        },
+        []() {
+          // Handle completion
+        });
+
+    // Only drop the output edges if we are rank 0
+    if (ctx.rank() == 0) {
+      // Need to drop the output edges
+      mrc::node::SourceProperties<output_t>::release_edge_connection();
+      mrc::node::SinkProperties<T>::release_edge_connection();
+    }
+  }
+
+  /**
+   * @brief Runnable's state control, for stopping from MRC.
+   */
+  void on_state_update(const state_t &state) final {
+    switch (state) {
+    case state_t::Stop:
+      // Do nothing, we wait for the upstream channel to return closed
+      // m_stop_source.request_stop();
+      break;
+
+    case state_t::Kill:
+      m_stop_source.request_stop();
+      break;
+
+    default:
+      break;
+    }
+  }
+
+  std::stop_source m_stop_source;
+  int m_max_count;
+  std::chrono::milliseconds m_duration;
+};
+} // namespace mrc::node

cpp/mrc/tests/test_segment.cpp

@@ -20,6 +20,7 @@
 #include "mrc/benchmarking/trace_statistics.hpp"
 #include "mrc/exceptions/runtime_error.hpp"
 #include "mrc/node/operators/broadcast.hpp"
+#include "mrc/node/operators/dynamic_batcher.hpp"
 #include "mrc/node/rx_node.hpp"
 #include "mrc/node/rx_sink.hpp"
 #include "mrc/node/rx_source.hpp"
@@ -1122,4 +1123,46 @@ TEST_F(TestSegment, SegmentGetEgressNotEgressError)
     */
 }
 
+TEST_F(TestSegment, SegmentDynamicBatcher)
+{
+    unsigned int iterations{3};
+    std::atomic<unsigned int> sink1_results{0};
+    float sink2_results{0};
+    std::mutex mux;
+
+    auto init = [&](segment::IBuilder& segment) {
+        auto src = segment.make_source<int>("src", [&](rxcpp::subscriber<int>& s) {
+            for (size_t i = 0; i < iterations && s.is_subscribed(); i++)
+            {
+                s.on_next(1);
+                s.on_next(2);
+                s.on_next(3);
+            }
+
+            s.on_completed();
+        });
+
+        auto dynamic_batcher = segment.construct_object<node::DynamicBatcher<int, runnable::Context>>("dynamic_batcher", 2, std::chrono::milliseconds(100));
+
+        segment.make_edge(src, dynamic_batcher);
+
+        auto sink = segment.make_sink<std::vector<int>>("sink", [&](std::vector<int> x) {
+            DVLOG(1) << "Sink got vector" << std::endl;
+            for (auto i : x)
+            {
+                DVLOG(1) << "Sink got value: " << i << std::endl;
+                // sink1_results.fetch_add(i, std::memory_order_relaxed);
+            }
+        });
+
+        segment.make_edge(dynamic_batcher, sink);
+    };
+
+    auto segdef = Segment::create("dynamic_batcher_test", init);
+
+    auto pipeline = mrc::make_pipeline();
+    pipeline->register_segment(std::move(segdef));
+    execute_pipeline(std::move(pipeline));
+}
+
 }  // namespace mrc

mrc.code-workspace

@@ -86,25 +86,49 @@
                 "type": "cppdbg"
             },
             {
-                "MIMode": "gdb",
+                "MIMode": "lldb",
                 "args": [],
                 "cwd": "${workspaceFolder}",
                 "environment": [],
                 "externalConsole": false,
-                "miDebuggerPath": "gdb",
-                "name": "debug bench_mrc.x",
-                "preLaunchTask": "C/C++: g++ build active file",
-                "program": "${workspaceFolder}/build/benchmarks/bench_mrc",
+                "miDebuggerPath": "lldb",
+                "name": "debug test_mrc.x with lldb",
+                // "preLaunchTask": "C/C++: g++ build active file",
+                "program": "${workspaceFolder}/build/cpp/mrc/tests/test_mrc.x",
                 "request": "launch",
                 "setupCommands": [
                     {
-                        "description": "Enable pretty-printing for gdb",
+                        "description": "Enable pretty-printing for lldb",
                         "ignoreFailures": true,
-                        "text": "-enable-pretty-printing"
+                        "text": "command script import pretty_printers.py"
                     }
                 ],
+                "justMyCode": true,
                 "stopAtEntry": false,
-                "type": "cppdbg"
+                "type": "lldb"
+            },
+            {
+                "MIMode": "lldb",
+                "args": [],
+                "cwd": "${workspaceFolder}",
+                "environment": [],
+                "externalConsole": false,
+                "miDebuggerPath": "lldb",
+                "name": "debug TestSegment.SegmentDynamicBatcher with lldb",
+                // "preLaunchTask": "C/C++: g++ build active file",
+                "program": "${workspaceFolder}/build/cpp/mrc/tests/test_mrc.x",
+                "request": "launch",
+                "setupCommands": [
+                    {
+                        "description": "Enable pretty-printing for lldb",
+                        "ignoreFailures": true,
+                        "text": "command script import pretty_printers.py"
+                    }
+                ],
+                "args": ["--gtest_filter=TestSegment.SegmentDynamicBatcher"],
+                "justMyCode": true,
+                "stopAtEntry": false,
+                "type": "lldb"
             },
             {
                 "MIMode": "gdb",