/**
* Write out an info file under the region directory. Useful recovering mangled regions.
*
* @param regionInfoContent serialized version of the {@link HRegionInfo}
* @param useTempDir indicate whether or not using the region .tmp dir for a safer file creation.
*/
private void writeRegionInfoOnFilesystem(final byte[] regionInfoContent, final boolean useTempDir)
throws IOException {
Path regionInfoFile = new Path(getRegionDir(), REGION_INFO_FILE);
if (useTempDir) {
// Create in tmpDir and then move into place in case we crash after
// create but before close. If we don't successfully close the file,
// subsequent region reopens will fail the below because create is
// registered in NN.
// And then create the file
Path tmpPath = new Path(getTempDir(), REGION_INFO_FILE);
// If datanode crashes or if the RS goes down just before the close is called while trying to
// close the created regioninfo file in the .tmp directory then on next
// creation we will be getting AlreadyCreatedException.
// Hence delete and create the file if exists.
if (FSUtils.isExists(fs, tmpPath)) {
FSUtils.delete(fs, tmpPath, true);
}
// Write HRI to a file in case we need to recover hbase:meta
writeRegionInfoFileContent(conf, fs, tmpPath, regionInfoContent);
// Move the created file to the original path
if (fs.exists(tmpPath) && !rename(tmpPath, regionInfoFile)) {
throw new IOException("Unable to rename " + tmpPath + " to " + regionInfoFile);
}
} else {
// Write HRI to a file in case we need to recover hbase:meta
writeRegionInfoFileContent(conf, fs, regionInfoFile, regionInfoContent);
}
}
