Commit 9d07c41b authored Aug 18, 2021 by Alex Buynytskyy

Slightly more efficient job storage.

Use binary XML:
- less space on disk: 500 jobs file size 99093b vs 177982b
- slightly better reading times: see perf test,
- less memory usage: 2.7M (https://pprof.corp.google.com/?id=ab851a8e29fa10e4e31635d9b7219be5&tab=tree&focus=writeJobsMapImpl) vs 130K (https://pprof.corp.google.com/?id=41244f6c3fa65f54b930087939a28231&tab=tree&focus=writeJobsMapImpl).

BEFORE:
[1/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_fewJobs_badRTC: PASSED (20.018s)
	testPersistedJobReading_fewJobs_badRTC_mean: 4403782
	testPersistedJobReading_fewJobs_badRTC_mean: 4329086
	testPersistedJobReading_fewJobs_badRTC_mean: 4361577
[2/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobWriting_manyJobs: PASSED (20.894s)
	testPersistedJobWriting_manyJobs_mean: 33269431
	testPersistedJobWriting_manyJobs_mean: 32886187
	testPersistedJobWriting_manyJobs_mean: 33093695
[3/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_manyJobs_goodRTC: PASSED (20.822s)
	testPersistedJobReading_manyJobs_goodRTC_mean: 39305058
	testPersistedJobReading_manyJobs_goodRTC_mean: 38768541
	testPersistedJobReading_manyJobs_goodRTC_mean: 38944530
[4/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobWriting_fewJobs: PASSED (21.046s)
	testPersistedJobWriting_fewJobs_mean: 4301181
	testPersistedJobWriting_fewJobs_mean: 4164938
	testPersistedJobWriting_fewJobs_mean: 4146446
[5/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_fewJobs_goodRTC: PASSED (21.137s)
	testPersistedJobReading_fewJobs_goodRTC_mean: 4230574
	testPersistedJobReading_fewJobs_goodRTC_mean: 4184341
	testPersistedJobReading_fewJobs_goodRTC_mean: 4192015
[6/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_manyJobs_badRTC: PASSED (21.016s)
	testPersistedJobReading_manyJobs_badRTC_mean: 39166861
	testPersistedJobReading_manyJobs_badRTC_mean: 39049685
	testPersistedJobReading_manyJobs_badRTC_mean: 38929124

AFTER:
[1/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_fewJobs_badRTC: PASSED (19.525s)
	testPersistedJobReading_fewJobs_badRTC_mean: 4082319
	testPersistedJobReading_fewJobs_badRTC_mean: 4067636
	testPersistedJobReading_fewJobs_badRTC_mean: 4066729
[2/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobWriting_manyJobs: PASSED (20.965s)
	testPersistedJobWriting_manyJobs_mean: 32787281
	testPersistedJobWriting_manyJobs_mean: 32545741
	testPersistedJobWriting_manyJobs_mean: 33066635
[3/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_manyJobs_goodRTC: PASSED (20.917s)
	testPersistedJobReading_manyJobs_goodRTC_mean: 36971876
	testPersistedJobReading_manyJobs_goodRTC_mean: 36671859
	testPersistedJobReading_manyJobs_goodRTC_mean: 37033008
[4/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobWriting_fewJobs: PASSED (21.171s)
	testPersistedJobWriting_fewJobs_mean: 4271303
	testPersistedJobWriting_fewJobs_mean: 4205693
	testPersistedJobWriting_fewJobs_mean: 4135812
[5/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_fewJobs_goodRTC: PASSED (20.992s)
	testPersistedJobReading_fewJobs_goodRTC_mean: 3914909
	testPersistedJobReading_fewJobs_goodRTC_mean: 3897198
	testPersistedJobReading_fewJobs_goodRTC_mean: 3932903
[6/6] com.android.frameworks.perftests.job.JobStorePerfTests#testPersistedJobReading_manyJobs_badRTC: PASSED (20.995s)
	testPersistedJobReading_manyJobs_badRTC_mean: 37105827
	testPersistedJobReading_manyJobs_badRTC_mean: 36804174
	testPersistedJobReading_manyJobs_badRTC_mean: 36943056

Bug: 135200955
Fixes: 135200955
Test: atest CtsJobSchedulerTestCases JobStoreTest JobStorePerfTests
Change-Id: I611c6fb8df029050a7e3ee300547152016a08f5c

parent 98ed025e

apex/jobscheduler/service/java/com/android/server/job/JobStore.java

+9 −18

Original line number	Diff line number	Diff line
		@@ -41,13 +41,13 @@ import android.util.Pair;
		import android.util.Slog;
		import android.util.SparseArray;
		import android.util.SystemConfigFileCommitEventLogger;
		import android.util.TypedXmlSerializer;
		import android.util.Xml;

		import com.android.internal.annotations.GuardedBy;
		import com.android.internal.annotations.VisibleForTesting;
		import com.android.internal.util.ArrayUtils;
		import com.android.internal.util.BitUtils;
		import com.android.internal.util.FastXmlSerializer;
		import com.android.server.IoThread;
		import com.android.server.LocalServices;
		import com.android.server.job.JobSchedulerInternal.JobStorePersistStats;
		@@ -57,13 +57,12 @@ import org.xmlpull.v1.XmlPullParser;
		import org.xmlpull.v1.XmlPullParserException;
		import org.xmlpull.v1.XmlSerializer;

		import java.io.ByteArrayOutputStream;
		import java.io.File;
		import java.io.FileInputStream;
		import java.io.FileNotFoundException;
		import java.io.FileOutputStream;
		import java.io.IOException;
		import java.nio.charset.StandardCharsets;
		import java.io.InputStream;
		import java.util.ArrayList;
		import java.util.List;
		import java.util.Set;
		@@ -469,11 +468,9 @@ public final class JobStore {
		int numJobs = 0;
		int numSystemJobs = 0;
		int numSyncJobs = 0;
		try {
		mEventLogger.setStartTime(SystemClock.uptimeMillis());
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		XmlSerializer out = new FastXmlSerializer();
		out.setOutput(baos, StandardCharsets.UTF_8.name());
		try (FileOutputStream fos = mJobsFile.startWrite()) {
		TypedXmlSerializer out = Xml.resolveSerializer(fos);
		out.startDocument(null, true);
		out.setFeature("http://xmlpull.org/v1/doc/features.html#indent-output", true);

		@@ -502,9 +499,6 @@ public final class JobStore {
		out.endTag(null, "job-info");
		out.endDocument();

		// Write out to disk in one fell swoop.
		FileOutputStream fos = mJobsFile.startWrite();
		fos.write(baos.toByteArray());
		mJobsFile.finishWrite(fos);
		} catch (IOException e) {
		if (DEBUG) {
		@@ -703,9 +697,8 @@ public final class JobStore {
		int numJobs = 0;
		int numSystemJobs = 0;
		int numSyncJobs = 0;
		try {
		List<JobStatus> jobs;
		FileInputStream fis = mJobsFile.openRead();
		try (FileInputStream fis = mJobsFile.openRead()) {
		synchronized (mLock) {
		jobs = readJobMapImpl(fis, rtcGood);
		if (jobs != null) {
		@@ -726,7 +719,6 @@ public final class JobStore {
		}
		}
		}
		fis.close();
		} catch (FileNotFoundException e) {
		if (DEBUG) {
		Slog.d(TAG, "Could not find jobs file, probably there was nothing to load.");
		@@ -743,10 +735,9 @@ public final class JobStore {
		Slog.i(TAG, "Read " + numJobs + " jobs");
		}

		private List<JobStatus> readJobMapImpl(FileInputStream fis, boolean rtcIsGood)
		private List<JobStatus> readJobMapImpl(InputStream fis, boolean rtcIsGood)
		throws XmlPullParserException, IOException {
		XmlPullParser parser = Xml.newPullParser();
		parser.setInput(fis, StandardCharsets.UTF_8.name());
		XmlPullParser parser = Xml.resolvePullParser(fis);

		int eventType = parser.getEventType();
		while (eventType != XmlPullParser.START_TAG &&