@Override
  public CompletableFuture<Void> deleteAllAsync(List<K> keys, Object ... args) {
    incCounter(metrics.numDeleteAlls);
    long startNs = clock.nanoTime();
    Preconditions.checkNotNull(table, "Cannot delete from a read-only table: " + table);
    return table.deleteAllAsync(keys, args).handle((result, e) -> {
      if (e != null) {
        throw new SamzaException("Failed to delete the record for " + keys, e);
      } else if (!isWriteAround) {
        cache.deleteAll(keys, args);
      }
      updateTimer(metrics.deleteAllNs, clock.nanoTime() - startNs);
      return result;
    });
  }
Lookup the cache and return the keys that are missed in cache
@param keys keys to be looked up
@param records result map
@return list of keys missed in the cache
samza-core/src/main/java/org/apache/samza/table/caching/CachingTable.java