code: static void checkDirectMemCapacity(final int k, final long n, final long memCapBytes) {
      final int reqBufBytes = getCompactStorageBytes(k, n);
  
      if (memCapBytes < reqBufBytes) {
        throw new SketchesArgumentException("Possible corruption: Memory capacity too small: "
            + memCapBytes + " < " + reqBufBytes);
      }
    }
docs: Checks the validity of the direct memory capacity assuming n, k.
  @param k the given value of k
  @param n the given value of n
  @param memCapBytes the current memory capacity in bytes