/** Create a new checkpoint */
void doCheckpoint() throws IOException {
// Do the required initialization of the merge work area.
startCheckpoint();
// Tell the namenode to start logging transactions in a new edit file
// Returns a token that would be used to upload the merged image.
CheckpointSignature sig = namenode.rollEditLog();
// error simulation code for junit test
if (ErrorSimulator.getErrorSimulation(0)) {
throw new IOException("Simulating error0 " + "after creating edits.new");
}
downloadCheckpointFiles(sig); // Fetch fsimage and edits
doMerge(sig); // Do the merge
//
// Upload the new image into the NameNode. Then tell the Namenode
// to make this new uploaded image as the most current image.
//
putFSImage(sig);
// error simulation code for junit test
if (ErrorSimulator.getErrorSimulation(1)) {
throw new IOException("Simulating error1 " + "after uploading new image to NameNode");
}
namenode.rollFsImage();
checkpointImage.endCheckpoint();
LOG.warn("Checkpoint done. New Image Size: " + checkpointImage.getFsImageName().length());
}
//
// The main work loop
//
public void run() {
//
// Poll the Namenode (once every 5 minutes) to find the size of the
// pending edit log.
//
long period = 5 * 60; // 5 minutes
long lastCheckpointTime = 0;
if (checkpointPeriod < period) {
period = checkpointPeriod;
}
while (shouldRun) {
try {
Thread.sleep(1000 * period);
} catch (InterruptedException ie) {
// do nothing
}
if (!shouldRun) {
break;
}
try {
long now = System.currentTimeMillis();
long size = namenode.getEditLogSize();
if (size >= checkpointSize || now >= lastCheckpointTime + 1000 * checkpointPeriod) {
doCheckpoint();
lastCheckpointTime = now;
}
} catch (IOException e) {
LOG.error("Exception in doCheckpoint: ");
LOG.error(StringUtils.stringifyException(e));
e.printStackTrace();
checkpointImage.imageDigest = null;
} catch (Throwable e) {
LOG.error("Throwable Exception in doCheckpoint: ");
LOG.error(StringUtils.stringifyException(e));
e.printStackTrace();
Runtime.getRuntime().exit(-1);
}
}
}
/**
* @param argv The parameters passed to this program.
* @exception Exception if the filesystem does not exist.
* @return 0 on success, non zero on error.
*/
private int processArgs(String[] argv) throws Exception {
if (argv.length < 1) {
printUsage("");
return -1;
}
int exitCode = -1;
int i = 0;
String cmd = argv[i++];
//
// verify that we have enough command line parameters
//
if ("-geteditsize".equals(cmd)) {
if (argv.length != 1) {
printUsage(cmd);
return exitCode;
}
} else if ("-checkpoint".equals(cmd)) {
if (argv.length != 1 && argv.length != 2) {
printUsage(cmd);
return exitCode;
}
if (argv.length == 2 && !"force".equals(argv[i])) {
printUsage(cmd);
return exitCode;
}
}
exitCode = 0;
try {
if ("-checkpoint".equals(cmd)) {
long size = namenode.getEditLogSize();
if (size >= checkpointSize || argv.length == 2 && "force".equals(argv[i])) {
doCheckpoint();
} else {
System.err.println(
"EditLog size "
+ size
+ " bytes is "
+ "smaller than configured checkpoint "
+ "size "
+ checkpointSize
+ " bytes.");
System.err.println("Skipping checkpoint.");
}
} else if ("-geteditsize".equals(cmd)) {
long size = namenode.getEditLogSize();
System.out.println("EditLog size is " + size + " bytes");
} else {
exitCode = -1;
LOG.error(cmd.substring(1) + ": Unknown command");
printUsage("");
}
} catch (RemoteException e) {
//
// This is a error returned by hadoop server. Print
// out the first line of the error mesage, ignore the stack trace.
exitCode = -1;
try {
String[] content;
content = e.getLocalizedMessage().split("\n");
LOG.error(cmd.substring(1) + ": " + content[0]);
} catch (Exception ex) {
LOG.error(cmd.substring(1) + ": " + ex.getLocalizedMessage());
}
} catch (IOException e) {
//
// IO exception encountered locally.
//
exitCode = -1;
LOG.error(cmd.substring(1) + ": " + e.getLocalizedMessage());
} finally {
// Does the RPC connection need to be closed?
}
return exitCode;
}