# Decommissioning

Decommissiong is a mechanism in MinIO to drain older pools (usually with old hardware) and migrate the content from such pools to a newer pools (usually better hardware). Decommissioning spreads the data across all pools - for example, if you decommission `pool1`, all the data from `pool1` spreads across `pool2` and `pool3`.

## Features

     * will still be present. If the composed Executor is an ExecutorService, it can respond to
     * shutdown() by returning tasks queued on that Thread after {@link #worker} drains the queue.
     */
    @SuppressWarnings("CatchingUnchecked") // sneaky checked exception
    private void workOnQueue() {
      boolean interruptedDuringTask = false;
      boolean hasSetRunning = false;

     * will still be present. If the composed Executor is an ExecutorService, it can respond to
     * shutdown() by returning tasks queued on that Thread after {@link #worker} drains the queue.
     */
    @SuppressWarnings("CatchingUnchecked") // sneaky checked exception
    private void workOnQueue() {
      boolean interruptedDuringTask = false;
      boolean hasSetRunning = false;

	}

	bp.Put(b)

	// Check the size of the pool.
	if uint64(len(bp.c)) != size {
		t.Fatalf("bytepool size invalid: got %v want %v", len(bp.c), size)
	}

	// lets drain the buf channel first before we validate invalid buffers.
	for i := uint64(0); i < size; i++ {
		bp.Get() // discard
	}

	// Try putting some invalid buffers into pool

	return dstRec, nil
}

// Close - closes underlying reader.
func (r *Reader) Close() error {
	// Close the input.
	err := r.readCloser.Close()
	for range r.valueCh {
		// Drain values so we don't leak a goroutine.
		// Since we have closed the input, it should fail rather quickly.
	}
	return err
}

// NewReader - creates new JSON reader using readCloser.

     * list's ordering. It is drained as a batch operation when either the DRAIN_THRESHOLD is
     * crossed or a write occurs on the segment.
     */
    final Queue<ReferenceEntry<K, V>> recencyQueue;

    /**
     * A counter of the number of reads since the last write, used to drain queues on a small
     * fraction of read operations.
     */

func (s *Stream) Results(next func(b []byte) error) (err error) {
	done := false
	defer func() {
		if s.cancel != nil {
			s.cancel(err)
		}

		if !done {
			// Drain channel.
			for range s.responses {
			}
		}
	}()
	doneCh := s.ctx.Done()
	for {
		select {
		case <-doneCh:
			if err := context.Cause(s.ctx); !errors.Is(err, errStreamEOF) {
				return err
			}

		c = 2 * cap(b)
	}
	b2 := append([]byte(nil), make([]byte, c)...)
	i := copy(b2, b)
	return b2[:i]
}

// WriteTo writes data to w until the buffer is drained or an error occurs.
// The return value n is the number of bytes written; it always fits into an
// int, but it is int64 to match the [io.WriterTo] interface. Any error
// encountered during the write is also returned.

	h          hash.Hash
	shardSize  int64
	hashBytes  []byte
}

func (b *streamingBitrotReader) Close() error {
	if b.rc == nil {
		return nil
	}
	if closer, ok := b.rc.(io.Closer); ok {
		// drain the body for connection reuse at network layer.
		xhttp.DrainBody(io.NopCloser(b.rc))
		return closer.Close()
	}
	return nil
}

func (b *streamingBitrotReader) ReadAt(buf []byte, offset int64) (int, error) {

   *
   * This implementation uses a per-segment queue to record a memento of the additions, removals,
   * and accesses that were performed on the map. The queue is drained on writes and when it exceeds
   * its capacity threshold.
   *
   * The Least Recently Used page replacement algorithm was chosen due to its simplicity, high hit