perf(sim/flow): Add support for multi-flow stages

This change adds support for creating nodes in a flow graph that support
multiple inputs and outputs directly, instead of our current approach
where we need to re-implement the `FlowConsumerContext` interface in
order to support multiple inputs or outputs.

2 files changed, 109 insertions, 1 deletions

diff --git a/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow/FlowBenchmarks.kt b/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow/FlowBenchmarks.kt
index 58f84d82..9e0a4a5e 100644
--- a/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow/FlowBenchmarks.kt
+++ b/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow/FlowBenchmarks.kt
@@ -47,7 +47,7 @@ class FlowBenchmarks {
     @Setup
     fun setUp() {
         val random = ThreadLocalRandom.current()
-        val entries = List(10000) { TraceFlowSource.Fragment(1000, random.nextDouble(0.0, 4500.0)) }
+        val entries = List(1000000) { TraceFlowSource.Fragment(1000, random.nextDouble(0.0, 4500.0)) }
         trace = entries.asSequence()
     }
 
diff --git a/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow2/FlowBenchmarks.kt b/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow2/FlowBenchmarks.kt
new file mode 100644
index 00000000..1b0e2e9e
--- /dev/null
+++ b/opendc-simulator/opendc-simulator-flow/src/jmh/kotlin/org/opendc/simulator/flow2/FlowBenchmarks.kt
@@ -0,0 +1,108 @@
+/*
+ * Copyright (c) 2021 AtLarge Research
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in all
+ * copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+package org.opendc.simulator.flow2
+
+import kotlinx.coroutines.launch
+import org.opendc.simulator.flow2.mux.MaxMinFlowMultiplexer
+import org.opendc.simulator.flow2.sink.SimpleFlowSink
+import org.opendc.simulator.flow2.source.TraceFlowSource
+import org.opendc.simulator.kotlin.runSimulation
+import org.openjdk.jmh.annotations.Benchmark
+import org.openjdk.jmh.annotations.Fork
+import org.openjdk.jmh.annotations.Measurement
+import org.openjdk.jmh.annotations.Scope
+import org.openjdk.jmh.annotations.Setup
+import org.openjdk.jmh.annotations.State
+import org.openjdk.jmh.annotations.Warmup
+import java.util.concurrent.ThreadLocalRandom
+import java.util.concurrent.TimeUnit
+
+@State(Scope.Thread)
+@Fork(1)
+@Warmup(iterations = 2, time = 1, timeUnit = TimeUnit.SECONDS)
+@Measurement(iterations = 5, time = 3, timeUnit = TimeUnit.SECONDS)
+class FlowBenchmarks {
+    private lateinit var trace: TraceFlowSource.Trace
+
+    @Setup
+    fun setUp() {
+        val random = ThreadLocalRandom.current()
+        val traceSize = 10_000_000
+        trace = TraceFlowSource.Trace(
+            LongArray(traceSize) { (it + 1) * 1000L },
+            FloatArray(traceSize) { random.nextFloat(0.0f, 4500.0f) },
+            traceSize
+        )
+    }
+
+    @Benchmark
+    fun benchmarkSink() {
+        return runSimulation {
+            val engine = FlowEngine.create(coroutineContext, clock)
+            val graph = engine.newGraph()
+            val sink = SimpleFlowSink(graph, 4200.0f)
+            val source = TraceFlowSource(graph, trace)
+            graph.connect(source.output, sink.input)
+        }
+    }
+
+    @Benchmark
+    fun benchmarkMuxMaxMinSingleSource() {
+        return runSimulation {
+            val engine = FlowEngine.create(coroutineContext, clock)
+            val graph = engine.newGraph()
+            val switch = MaxMinFlowMultiplexer(graph)
+
+            val sinkA = SimpleFlowSink(graph, 3000.0f)
+            val sinkB = SimpleFlowSink(graph, 3000.0f)
+
+            graph.connect(switch.newOutput(), sinkA.input)
+            graph.connect(switch.newOutput(), sinkB.input)
+
+            val source = TraceFlowSource(graph, trace)
+            graph.connect(source.output, switch.newInput())
+        }
+    }
+
+    @Benchmark
+    fun benchmarkMuxMaxMinTripleSource() {
+        return runSimulation {
+            val engine = FlowEngine.create(coroutineContext, clock)
+            val graph = engine.newGraph()
+            val switch = MaxMinFlowMultiplexer(graph)
+
+            val sinkA = SimpleFlowSink(graph, 3000.0f)
+            val sinkB = SimpleFlowSink(graph, 3000.0f)
+
+            graph.connect(switch.newOutput(), sinkA.input)
+            graph.connect(switch.newOutput(), sinkB.input)
+
+            repeat(3) {
+                launch {
+                    val source = TraceFlowSource(graph, trace)
+                    graph.connect(source.output, switch.newInput())
+                }
+            }
+        }
+    }
+}