private void writeStatsToLocalBackupFile() throws IOException {
    File tempFile = new File(config.localBackupFilePath + ".tmp");
    File destFile = new File(config.localBackupFilePath);
    if (tempFile.createNewFile()) {
      objectMapper.writeValue(tempFile, previousHostAccountStorageStatsWrapper);
      if (!tempFile.renameTo(destFile)) {
        throw new IOException("Failed to rename " + tempFile.getAbsolutePath() + " to " + destFile.getAbsolutePath());
      }
    } else {
      throw new IOException("Temporary file creation failed when publishing stats " + tempFile.getAbsolutePath());
    }
  }
Read all the container storage usage from local backup file.
ambry-mysql/src/main/java/com/github/ambry/accountstats/AccountStatsMySqlStore.java