foundationdb/fdbserver/workloads/AsyncFileWrite.actor.cpp

/*
 * AsyncFileWrite.actor.cpp
 *
 * This source file is part of the FoundationDB open source project
 *
 * Copyright 2013-2018 Apple Inc. and the FoundationDB project authors
 *
 * 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.
 */

#include "fdbserver/workloads/workloads.actor.h"
#include "flow/ActorCollection.h"
#include "flow/SystemMonitor.h"
#include "fdbrpc/IAsyncFile.h"
#include "fdbserver/workloads/AsyncFile.actor.h"
#include "flow/actorcompiler.h"  // This must be the last #include.

struct AsyncFileWriteWorkload : public AsyncFileWorkload
{
	//Buffer used to store what is being written
	Reference<AsyncFileBuffer> writeBuffer;

	//The futures for the asynchronous write futures
	vector<Future<Void> > writeFutures;

	//Number of writes to perform in parallel.  Write tests are performed only if this is greater than zero and numParallelReads is zero
	int numParallelWrites;

	//The number of bytes written in each call of write
	int writeSize;

	//Whether or not writes should be performed sequentially
	bool sequential;

	double averageCpuUtilization;
	PerfIntCounter bytesWritten;

	AsyncFileWriteWorkload(WorkloadContext const& wcx)
		: AsyncFileWorkload(wcx), bytesWritten("Bytes Written"), writeBuffer(nullptr)
	{
		numParallelWrites = getOption(options, LiteralStringRef("numParallelWrites"), 0);
		writeSize = getOption(options, LiteralStringRef("writeSize"), _PAGE_SIZE);
		fileSize = getOption(options, LiteralStringRef("fileSize"), 10002432);
		sequential = getOption(options, LiteralStringRef("sequential"), true);
	}

	std::string description() const override { return "AsyncFileWrite"; }

	Future<Void> setup(Database const& cx) override {
		if(enabled)
			return _setup(this);

		return Void();
	}

	ACTOR Future<Void> _setup(AsyncFileWriteWorkload *self)
	{
		//Allow only 4K aligned writes if using unbuffered IO
		if(self->unbufferedIO && self->writeSize % AsyncFileWorkload::_PAGE_SIZE != 0)
			self->writeSize = std::max(AsyncFileWorkload::_PAGE_SIZE, self->writeSize - self->writeSize % AsyncFileWorkload::_PAGE_SIZE);

		//Allocate the write buffer
		self->writeBuffer = self->allocateBuffer(self->writeSize);

		int64_t initialSize = self->fileSize;
		if(self->sequential)
			initialSize = 0;

		wait(self->openFile(self, IAsyncFile::OPEN_READWRITE, 0666, initialSize));

		int64_t fileSize = wait(self->fileHandle->file->size());
		if(fileSize != 0)
			self->fileSize = fileSize;

		return Void();
	}

	Future<Void> start(Database const& cx) override {
		if(enabled)
			return _start(this);

		return Void();
	}

	ACTOR Future<Void> _start(AsyncFileWriteWorkload *self)
	{
		state StatisticsState statState;
		customSystemMonitor("AsyncFile Metrics", &statState);

		wait(timeout(self->runWriteTest(self), self->testDuration, Void()));

		SystemStatistics stats = customSystemMonitor("AsyncFile Metrics", &statState);
		self->averageCpuUtilization = stats.processCPUSeconds / stats.elapsed;

		//Try to let the IO complete so we can clean up after them
		wait(timeout(waitForAll(self->writeFutures), 10, Void()));

		return Void();
	}

	ACTOR Future<Void> runWriteTest(AsyncFileWriteWorkload *self)
	{
		state int64_t offset = self->fileSize;
		state Future<Void> prevSync = Void();
		loop
		{
			//Write chunks of the file using different actors
			for(int i = 0; i < self->numParallelWrites; i++)
			{
				//Perform the write.  Don't allow it to be cancelled (because the underlying IO may not be cancellable) and don't allow
				//objects that the write uses to be deleted
				self->writeFutures.push_back
				(
					uncancellable
					(
						holdWhile
						(
							self->fileHandle,
							holdWhile(self->writeBuffer, self->fileHandle->file->write(self->writeBuffer->buffer, std::min((int64_t)self->writeSize, self->fileSize - offset), offset))
						)
					)
				);

				if(self->sequential)
				{
					offset += self->writeSize;

					//If the file is exhausted, start over at the beginning
					if(offset >= self->fileSize)
						offset = 0;
				}
				else if(self->unbufferedIO)
					offset = (int64_t)(deterministicRandom()->random01() * (self->fileSize - 1) / AsyncFileWorkload::_PAGE_SIZE) * AsyncFileWorkload::_PAGE_SIZE;
				else
					offset = (int64_t)(deterministicRandom()->random01() * (self->fileSize - 1));
			}

			wait(waitForAll(self->writeFutures));
			wait(prevSync);
			prevSync = self->fileHandle->file->sync();

			self->writeFutures.clear();

			self->bytesWritten += self->writeSize * self->numParallelWrites;
		}
	}

	void getMetrics(vector<PerfMetric>& m) override {
		if(enabled)
		{
			m.push_back(PerfMetric("Bytes written/sec", bytesWritten.getValue() / testDuration, false));
			m.push_back(PerfMetric("Average CPU Utilization (Percentage)", averageCpuUtilization * 100, false));
		}
	}
 };

WorkloadFactory<AsyncFileWriteWorkload> AsyncFileWriteWorkloadFactory("AsyncFileWrite");