And as you can have parallelism and asynchronicity at the same time, you get higher performance than most of the tested NodeJS frameworks and on par with Go, which is a compiled language closer to C [(all thanks to Starlette)](https://www.techempower.com/benchmarks/#section=data-r17&hw=ph&test=query&l=zijmkf-1).

### Is concurrency better than parallelism? { #is-concurrency-better-than-parallelism }

				case errors.Is(err, errDiskNotFound):
					atomic.AddInt32(&disksNotFound, 1)
				}

				// This will be communicated upstream.
				p.orgReaders[bufIdx] = nil
				if br, ok := p.readers[i].(io.Closer); ok {
					br.Close()
				}
				p.readers[i] = nil

				// Since ReadAt returned error, trigger another read.
				readTriggerCh <- true
				return
			}
			newBufLK.Lock()

		}
		w.Close()
		return errMoreData
	}

	// Only interested in flushing the size_t not mtime/atime
	if err = Fdatasync(w); err != nil {
		w.Close()
		return err
	}

	// Dealing with error returns from close() - 'man 2 close'
	//
	// A careful programmer will check the return value of close(), since it is quite possible that

func (r *Reader) Checksum() *Checksum {
	if !r.contentHash.Type.IsSet() || !r.contentHash.Valid() {
		return nil
	}
	return &r.contentHash
}

var _ io.Closer = (*Reader)(nil) // compiler check

// Close and release resources.

	}

	return fi.ToObjectInfo(srcBucket, srcObject, srcOpts.Versioned || srcOpts.VersionSuspended), nil
}

// GetObjectNInfo - returns object info and an object
// Read(Closer). When err != nil, the returned reader is always nil.
func (er erasureObjects) GetObjectNInfo(ctx context.Context, bucket, object string, rs *HTTPRangeSpec, h http.Header, opts ObjectOptions) (gr *GetObjectReader, err error) {

		err = func() (err error) {
			defer zippedFile.Close()
			extractedFilePath := filepath.Join(targetDir, file.Name)
			if file.FileInfo().IsDir() {
				return os.MkdirAll(extractedFilePath, file.Mode())
			}
			outputFile, err := os.OpenFile(extractedFilePath, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, file.Mode())
			if err != nil {
				return err
			}
			defer outputFile.Close()
			_, err = io.Copy(outputFile, zippedFile)

```
cat ${HADOOP_CONF_DIR}/core-site.xml | kv-pairify | grep "mapred"

mapred.maxthreads.generate.mapoutput=2 # Num threads to write map outputs
mapred.maxthreads.partition.closer=0 # Asynchronous map flushers
mapreduce.fileoutputcommitter.algorithm.version=2 # Use the latest committer version
mapreduce.job.reduce.slowstart.completedmaps=0.99 # 99% map, then reduce

    public LoadingValueReference() {
      this(LocalCache.<K, V>unset());
    }

    /*
     * TODO(cpovirk): Consider making this implementation closer to the mainline implementation.
     * (The difference was introduced as part of Java-8-specific changes in cl/132882204, but we
     * could probably make *some* of those changes here in the backport, too.)
     */

		// causing error.
		n, err := reader.Read(shard)
		w.Write(shard[:n])
		if err == nil {
			continue
		}
		if err == io.EOF {
			break
		}
		t.Fatal(err)
	}
	w.(io.Closer).Close()
	if err := storage.storage.bitrotVerify(t.Context(), pathJoin(path, volName, fileName), size, algo, nil, shardSize); err != nil {
		t.Fatal(err)
	}

	// 4) Streaming bitrot check on corrupted file

  `Tut, tut, child!' said the Duchess.  `Everything's got a
moral, if only you can find it.'  And she squeezed herself up
closer to Alice's side as she spoke.

  Alice did not much like keeping so close to her:  first,
because the Duchess was VERY ugly; and secondly, because she was
exactly the right height to rest her chin upon Alice's shoulder,
and it was an uncomfortably sharp chin.  However, she did not