/** Merge downloaded image and edits and write the new image into current storage directory. */
private void doMerge(CheckpointSignature sig, boolean loadImage) throws IOException {
if (loadImage) { // create an empty namespace if new image
namesystem = new FSNamesystem(checkpointImage, conf);
}
assert namesystem.dir.fsImage == checkpointImage;
checkpointImage.doMerge(sig, loadImage);
}
