From 831ba3d882a46dad2abe6ac281b736b729dc7080 Mon Sep 17 00:00:00 2001 From: Fabian Mastenbroek Date: Thu, 1 Apr 2021 21:14:34 +0200 Subject: serverless: Model cold start delays --- .../experiments/serverless/ServerlessExperiment.kt | 11 +++- .../serverless/simulator/SimFunctionDeployer.kt | 11 ++-- .../serverless/simulator/delay/ColdStartModel.kt | 69 ++++++++++++++++++++++ .../serverless/simulator/delay/DelayInjector.kt | 37 ++++++++++++ .../simulator/delay/StochasticDelayInjector.kt | 37 ++++++++++++ .../simulator/delay/ZeroDelayInjector.kt | 29 +++++++++ .../simulator/SimServerlessServiceTest.kt | 3 +- 7 files changed, 191 insertions(+), 6 deletions(-) create mode 100644 simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ColdStartModel.kt create mode 100644 simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/DelayInjector.kt create mode 100644 simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/StochasticDelayInjector.kt create mode 100644 simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ZeroDelayInjector.kt diff --git a/simulator/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt b/simulator/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt index e4dc6753..757617f8 100644 --- a/simulator/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt +++ b/simulator/opendc-experiments/opendc-experiments-serverless20/src/main/kotlin/org/opendc/experiments/serverless/ServerlessExperiment.kt @@ -37,6 +37,8 @@ import org.opendc.harness.dsl.anyOf import org.opendc.serverless.service.ServerlessService import org.opendc.serverless.service.router.RandomRoutingPolicy import org.opendc.serverless.simulator.SimFunctionDeployer +import org.opendc.serverless.simulator.delay.ColdStartModel +import org.opendc.serverless.simulator.delay.StochasticDelayInjector import org.opendc.simulator.compute.SimMachineModel import org.opendc.simulator.compute.model.MemoryUnit import org.opendc.simulator.compute.model.ProcessingNode @@ -44,6 +46,7 @@ import org.opendc.simulator.compute.model.ProcessingUnit import org.opendc.simulator.utils.DelayControllerClockAdapter import org.opendc.telemetry.sdk.toOtelClock import java.io.File +import java.util.* import kotlin.math.max /** @@ -71,6 +74,11 @@ public class ServerlessExperiment : Experiment("Serverless") { */ private val routingPolicy by anyOf(RandomRoutingPolicy()) + /** + * The cold start models to test. + */ + private val coldStartModel by anyOf(ColdStartModel.LAMBDA, ColdStartModel.AZURE, ColdStartModel.GOOGLE) + @OptIn(ExperimentalCoroutinesApi::class) override fun doRun(repeat: Int): Unit = runBlockingTest { val clock = DelayControllerClockAdapter(this) @@ -81,7 +89,8 @@ public class ServerlessExperiment : Experiment("Serverless") { val trace = ServerlessTraceReader().parse(tracePath) val traceById = trace.associateBy { it.id } - val deployer = SimFunctionDeployer(clock, this, createMachineModel()) { FunctionTraceWorkload(traceById.getValue(it.name)) } + val delayInjector = StochasticDelayInjector(coldStartModel, Random()) + val deployer = SimFunctionDeployer(clock, this, createMachineModel(), delayInjector) { FunctionTraceWorkload(traceById.getValue(it.name)) } val service = ServerlessService(coroutineContext, clock, meterProvider.get("opendc-serverless"), deployer, routingPolicy) val client = service.newClient() diff --git a/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/SimFunctionDeployer.kt b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/SimFunctionDeployer.kt index fd9d910a..2945a279 100644 --- a/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/SimFunctionDeployer.kt +++ b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/SimFunctionDeployer.kt @@ -28,6 +28,7 @@ import org.opendc.serverless.service.FunctionObject import org.opendc.serverless.service.deployer.FunctionDeployer import org.opendc.serverless.service.deployer.FunctionInstance import org.opendc.serverless.service.deployer.FunctionInstanceState +import org.opendc.serverless.simulator.delay.DelayInjector import org.opendc.serverless.simulator.workload.SimServerlessWorkloadMapper import org.opendc.simulator.compute.SimBareMetalMachine import org.opendc.simulator.compute.SimMachine @@ -48,6 +49,7 @@ public class SimFunctionDeployer( private val clock: Clock, private val scope: CoroutineScope, private val model: SimMachineModel, + private val delayInjector: DelayInjector, private val mapper: SimServerlessWorkloadMapper ) : FunctionDeployer { @@ -111,6 +113,8 @@ public class SimFunctionDeployer( internal fun start() { check(state == FunctionInstanceState.Provisioning) { "Invalid state of function instance" } job = scope.launch { + delay(delayInjector.getColdStartDelay(this@Instance)) + launch { try { machine.run(workload) @@ -120,12 +124,11 @@ public class SimFunctionDeployer( } while (isActive) { - chan.receive() - - if (queue.isNotEmpty()) { - state = FunctionInstanceState.Active + if (queue.isEmpty()) { + chan.receive() } + state = FunctionInstanceState.Active while (queue.isNotEmpty()) { val request = queue.poll() try { diff --git a/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ColdStartModel.kt b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ColdStartModel.kt new file mode 100644 index 00000000..f9f3718e --- /dev/null +++ b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ColdStartModel.kt @@ -0,0 +1,69 @@ +/* + * 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.serverless.simulator.delay + +/** + * Model parameters for the cold start times of serverless services. + */ +public enum class ColdStartModel { + // Min and max memory values from [Peeking Behind The Curtains of Serverless Platforms][2018], + // other values deduced from linear curve. + LAMBDA { + override fun coldStartParam(provisionedMemory: Int): Pair { + return when (provisionedMemory) { + 128 -> Pair(265.21, 354.43) + 256 -> Pair(261.46, 334.23) + 512 -> Pair(257.71, 314.03) + 1024 -> Pair(253.96, 293.83) + 1536 -> Pair(250.07, 273.63) + 2048 -> Pair(246.11, 253.43) + else -> Pair(0.0, 1.0) + } + } + }, + AZURE { + // Azure by default uses 1.5gb memory to instantiate functions + override fun coldStartParam(provisionedMemory: Int): Pair { + return Pair(242.66, 340.67) + } + }, + + GOOGLE { + override fun coldStartParam(provisionedMemory: Int): Pair { + return when (provisionedMemory) { + 128 -> Pair(493.04, 345.8) + 256 -> Pair(416.59, 301.5) + 512 -> Pair(340.14, 257.2) + 1024 -> Pair(263.69, 212.9) + 1536 -> Pair(187.24, 168.6) + 2048 -> Pair(110.77, 124.3) + else -> Pair(0.0, 1.0) + } + } + }; + + /** + * Obtain the stochastic parameters for the cold start models. + */ + public abstract fun coldStartParam(provisionedMemory: Int): Pair +} diff --git a/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/DelayInjector.kt b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/DelayInjector.kt new file mode 100644 index 00000000..f882031b --- /dev/null +++ b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/DelayInjector.kt @@ -0,0 +1,37 @@ +/* + * 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.serverless.simulator.delay + +import org.opendc.serverless.service.deployer.FunctionInstance + +/** + * An interface for modeling the delay caused by function cold starts. + */ +public interface DelayInjector { + /** + * Returns the cold start delay duration sampled from a normal distribution, the distribution is + * initialized using custom mean and standard deviation based on provisioned memory, language and + * failure model + */ + public fun getColdStartDelay(instance: FunctionInstance): Long +} diff --git a/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/StochasticDelayInjector.kt b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/StochasticDelayInjector.kt new file mode 100644 index 00000000..154378e1 --- /dev/null +++ b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/StochasticDelayInjector.kt @@ -0,0 +1,37 @@ +/* + * 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.serverless.simulator.delay + +import org.opendc.serverless.service.deployer.FunctionInstance +import java.util.* +import kotlin.math.abs + +/* + * Interface for instance deployment delay estimation. + */ +public class StochasticDelayInjector(private val model: ColdStartModel, private val random: Random) : DelayInjector { + override fun getColdStartDelay(instance: FunctionInstance): Long { + val (mean, sd) = model.coldStartParam(instance.function.memorySize.toInt()) + return abs(random.nextGaussian() * sd + mean).toLong() + } +} diff --git a/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ZeroDelayInjector.kt b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ZeroDelayInjector.kt new file mode 100644 index 00000000..0895ee18 --- /dev/null +++ b/simulator/opendc-serverless/opendc-serverless-simulator/src/main/kotlin/org/opendc/serverless/simulator/delay/ZeroDelayInjector.kt @@ -0,0 +1,29 @@ +/* + * 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.serverless.simulator.delay + +import org.opendc.serverless.service.deployer.FunctionInstance + +public object ZeroDelayInjector : DelayInjector { + override fun getColdStartDelay(instance: FunctionInstance): Long = 0 +} diff --git a/simulator/opendc-serverless/opendc-serverless-simulator/src/test/kotlin/org/opendc/serverless/simulator/SimServerlessServiceTest.kt b/simulator/opendc-serverless/opendc-serverless-simulator/src/test/kotlin/org/opendc/serverless/simulator/SimServerlessServiceTest.kt index 89998585..3a070475 100644 --- a/simulator/opendc-serverless/opendc-serverless-simulator/src/test/kotlin/org/opendc/serverless/simulator/SimServerlessServiceTest.kt +++ b/simulator/opendc-serverless/opendc-serverless-simulator/src/test/kotlin/org/opendc/serverless/simulator/SimServerlessServiceTest.kt @@ -34,6 +34,7 @@ import org.junit.jupiter.api.Test import org.junit.jupiter.api.assertAll import org.opendc.serverless.service.ServerlessService import org.opendc.serverless.service.router.RandomRoutingPolicy +import org.opendc.serverless.simulator.delay.ZeroDelayInjector import org.opendc.serverless.simulator.workload.SimServerlessWorkload import org.opendc.simulator.compute.SimMachineModel import org.opendc.simulator.compute.model.MemoryUnit @@ -68,7 +69,7 @@ internal class SimServerlessServiceTest { val workload = spyk(object : SimServerlessWorkload, SimWorkload by SimFlopsWorkload(1000) { override suspend fun invoke() {} }) - val deployer = SimFunctionDeployer(clock, this, machineModel) { workload } + val deployer = SimFunctionDeployer(clock, this, machineModel, ZeroDelayInjector) { workload } val service = ServerlessService(coroutineContext, clock, meter, deployer, RandomRoutingPolicy()) val client = service.newClient() -- cgit v1.2.3