@Override
    public boolean accept(Path path) {
      // skip meta table log -- ts.meta file
      if (AbstractFSWALProvider.isMetaFile(path)) {
        if (LOG.isDebugEnabled()) {
          LOG.debug("Skip .meta log file: " + path.getName());
        }
        return false;
      }
      long timestamp;
      try {
        timestamp = BackupUtils.getCreationTime(path);
        return timestamp > lastBackupTS;
      } catch (Exception e) {
        LOG.warn("Cannot read timestamp of log file " + path);
        return false;
      }
    }
For each region server: get all log files newer than the last timestamps but not newer than the
newest timestamps.
@param olderTimestamps  the timestamp for each region server of the last backup.
@param newestTimestamps the timestamp for each region server that the backup should lead to.
@param conf             the Hadoop and Hbase configuration
@param savedStartCode   the startcode (timestamp) of last successful backup.
@return a list of log files to be backed up
@throws IOException exception
hbase-backup/src/main/java/org/apache/hadoop/hbase/backup/impl/IncrementalBackupManager.java