HBASE-10537 Let the ExportSnapshot mapper fail and retry on error

git-svn-id: https://svn.apache.org/repos/asf/hbase/trunk@1569680 13f79535-47bb-0310-9956-ffa450edef68
This commit is contained in:
mbertozzi 2014-02-19 10:57:21 +00:00
parent 2514f24468
commit 96a5ef9131
2 changed files with 98 additions and 25 deletions

View File

@ -18,12 +18,14 @@
package org.apache.hadoop.hbase.snapshot;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Collections;
import java.util.Comparator;
import java.util.LinkedList;
import java.util.List;
import java.util.Random;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
@ -81,6 +83,9 @@ public final class ExportSnapshot extends Configured implements Tool {
private static final String CONF_OUTPUT_ROOT = "snapshot.export.output.root";
private static final String CONF_INPUT_ROOT = "snapshot.export.input.root";
static final String CONF_TEST_FAILURE = "test.snapshot.export.failure";
static final String CONF_TEST_RETRY = "test.snapshot.export.failure.retry";
private static final String INPUT_FOLDER_PREFIX = "export-files.";
// Export Map-Reduce Counters, to keep track of the progress
@ -90,6 +95,9 @@ public final class ExportSnapshot extends Configured implements Tool {
final static int REPORT_SIZE = 1 * 1024 * 1024;
final static int BUFFER_SIZE = 64 * 1024;
private boolean testFailures;
private Random random;
private boolean verifyChecksum;
private String filesGroup;
private String filesUser;
@ -117,6 +125,8 @@ public final class ExportSnapshot extends Configured implements Tool {
inputArchive = new Path(inputRoot, HConstants.HFILE_ARCHIVE_DIRECTORY);
outputArchive = new Path(outputRoot, HConstants.HFILE_ARCHIVE_DIRECTORY);
testFailures = conf.getBoolean(CONF_TEST_FAILURE, false);
try {
inputFs = FileSystem.get(inputRoot.toUri(), conf);
} catch (IOException e) {
@ -137,9 +147,8 @@ public final class ExportSnapshot extends Configured implements Tool {
Path outputPath = getOutputPath(inputPath);
LOG.info("copy file input=" + inputPath + " output=" + outputPath);
if (copyFile(context, inputPath, outputPath)) {
LOG.info("copy completed for input=" + inputPath + " output=" + outputPath);
}
copyFile(context, inputPath, outputPath);
LOG.info("copy completed for input=" + inputPath + " output=" + outputPath);
}
/**
@ -166,25 +175,55 @@ public final class ExportSnapshot extends Configured implements Tool {
return new Path(outputArchive, path);
}
private boolean copyFile(final Context context, final Path inputPath, final Path outputPath)
/*
* Used by TestExportSnapshot to simulate a failure
*/
private void injectTestFailure(final Context context, final Path inputPath)
throws IOException {
if (testFailures) {
if (context.getConfiguration().getBoolean(CONF_TEST_RETRY, false)) {
if (random == null) {
random = new Random();
}
// FLAKY-TEST-WARN: lower is better, we can get some runs without the
// retry, but at least we reduce the number of test failures due to
// this test exception from the same map task.
if (random.nextFloat() < 0.05) {
throw new IOException("TEST RETRY FAILURE: Unable to copy input=" + inputPath
+ " time=" + System.currentTimeMillis());
}
} else {
context.getCounter(Counter.COPY_FAILED).increment(1);
throw new IOException("TEST FAILURE: Unable to copy input=" + inputPath);
}
}
}
private void copyFile(final Context context, final Path inputPath, final Path outputPath)
throws IOException {
injectTestFailure(context, inputPath);
FSDataInputStream in = openSourceFile(inputPath);
if (in == null) {
context.getCounter(Counter.MISSING_FILES).increment(1);
return false;
throw new FileNotFoundException(inputPath.toString());
}
try {
// Verify if the input file exists
FileStatus inputStat = getFileStatus(inputFs, inputPath);
if (inputStat == null) return false;
if (inputStat == null) {
context.getCounter(Counter.MISSING_FILES).increment(1);
throw new FileNotFoundException(inputPath.toString());
}
// Verify if the output file exists and is the same that we want to copy
if (outputFs.exists(outputPath)) {
FileStatus outputStat = outputFs.getFileStatus(outputPath);
if (sameFile(inputStat, outputStat)) {
LOG.info("Skip copy " + inputPath + " to " + outputPath + ", same file.");
return true;
return;
}
}
@ -194,14 +233,13 @@ public final class ExportSnapshot extends Configured implements Tool {
outputFs.mkdirs(outputPath.getParent());
FSDataOutputStream out = outputFs.create(outputPath, true);
try {
if (!copyData(context, inputPath, in, outputPath, out, inputStat.getLen()))
return false;
copyData(context, inputPath, in, outputPath, out, inputStat.getLen());
} finally {
out.close();
}
// Preserve attributes
return preserveAttributes(outputPath, inputStat);
preserveAttributes(outputPath, inputStat);
} finally {
in.close();
}
@ -244,10 +282,11 @@ public final class ExportSnapshot extends Configured implements Tool {
return true;
}
private boolean copyData(final Context context,
private void copyData(final Context context,
final Path inputPath, final FSDataInputStream in,
final Path outputPath, final FSDataOutputStream out,
final long inputFileSize) {
final long inputFileSize)
throws IOException {
final String statusMessage = "copied %s/" + StringUtils.humanReadableInt(inputFileSize) +
" (%.3f%%)";
@ -280,17 +319,14 @@ public final class ExportSnapshot extends Configured implements Tool {
// Verify that the written size match
if (totalBytesWritten != inputFileSize) {
LOG.error("number of bytes copied not matching copied=" + totalBytesWritten +
" expected=" + inputFileSize + " for file=" + inputPath);
context.getCounter(Counter.COPY_FAILED).increment(1);
return false;
String msg = "number of bytes copied not matching copied=" + totalBytesWritten +
" expected=" + inputFileSize + " for file=" + inputPath;
throw new IOException(msg);
}
return true;
} catch (IOException e) {
LOG.error("Error copying " + inputPath + " to " + outputPath, e);
context.getCounter(Counter.COPY_FAILED).increment(1);
return false;
throw e;
}
}
@ -617,7 +653,7 @@ public final class ExportSnapshot extends Configured implements Tool {
if (outputFs.exists(snapshotTmpDir)) {
System.err.println("A snapshot with the same name '" + snapshotName + "' may be in-progress");
System.err.println("Please check " + snapshotTmpDir + ". If the snapshot has completed, ");
System.err.println("consider removing " + snapshotTmpDir + " before retrying export");
System.err.println("consider removing " + snapshotTmpDir + " before retrying export");
return 1;
}
@ -656,9 +692,9 @@ public final class ExportSnapshot extends Configured implements Tool {
snapshotTmpDir + " to=" + outputSnapshotDir);
return 1;
}
return 0;
} catch (Exception e) {
LOG.error("Snapshot export failed", e);
System.err.println("Snapshot export failed!");
e.printStackTrace(System.err);
outputFs.delete(outputSnapshotDir, true);

View File

@ -105,16 +105,14 @@ public class TestExportSnapshot {
emptySnapshotName = Bytes.toBytes("emptySnaptb0-" + tid);
// create Table
HTableDescriptor htd = new HTableDescriptor(tableName);
htd.addFamily(new HColumnDescriptor(FAMILY));
admin.createTable(htd, null);
SnapshotTestingUtils.createTable(TEST_UTIL, tableName, FAMILY);
// Take an empty snapshot
admin.snapshot(emptySnapshotName, tableName);
// Add some rows
HTable table = new HTable(TEST_UTIL.getConfiguration(), tableName);
TEST_UTIL.loadTable(table, FAMILY);
SnapshotTestingUtils.loadData(TEST_UTIL, tableName, 1000, FAMILY);
// take a snapshot
admin.snapshot(snapshotName, tableName);
@ -127,6 +125,7 @@ public class TestExportSnapshot {
SnapshotTestingUtils.deleteArchiveDirectory(TEST_UTIL);
}
/**
* Verfy the result of getBalanceSplits() method.
* The result are groups of files, used as input list for the "export" mappers.
@ -267,6 +266,44 @@ public class TestExportSnapshot {
fs.delete(copyDir, true);
}
/**
* Check that ExportSnapshot will return a failure if something fails.
*/
@Test
public void testExportFailure() throws Exception {
assertEquals(1, runExportAndInjectFailures(snapshotName, false));
}
/**
* Check that ExportSnapshot will succede if something fails but the retry succede.
*/
@Test
public void testExportRetry() throws Exception {
assertEquals(0, runExportAndInjectFailures(snapshotName, true));
}
/*
* Execute the ExportSnapshot job injecting failures
*/
private int runExportAndInjectFailures(final byte[] snapshotName, boolean retry)
throws Exception {
Path copyDir = TEST_UTIL.getDataTestDir("export-" + System.currentTimeMillis());
URI hdfsUri = FileSystem.get(TEST_UTIL.getConfiguration()).getUri();
FileSystem fs = FileSystem.get(copyDir.toUri(), new Configuration());
copyDir = copyDir.makeQualified(fs);
Configuration conf = new Configuration(TEST_UTIL.getConfiguration());
conf.setBoolean(ExportSnapshot.CONF_TEST_FAILURE, true);
conf.setBoolean(ExportSnapshot.CONF_TEST_RETRY, retry);
// Export Snapshot
int res = ExportSnapshot.innerMain(conf, new String[] {
"-snapshot", Bytes.toString(snapshotName),
"-copy-to", copyDir.toString()
});
return res;
}
/*
* verify if the snapshot folder on file-system 1 match the one on file-system 2
*/