import (
	"context"
	"fmt"
	"io"
	"sync"
)

// Writes in parallel to writers
type parallelWriter struct {
	writers     []io.Writer
	writeQuorum int
	errs        []error
}

// Write writes data to writers in parallel.
func (p *parallelWriter) Write(ctx context.Context, blocks [][]byte) error {
	var wg sync.WaitGroup

	for i := range p.writers {
		if p.writers[i] == nil {
			p.errs[i] = errDiskNotFound
			continue

	mimeXML mimeType = "application/xml"
)

// writeSuccessResponseJSON writes success headers and response if any,
// with content-type set to `application/json`.
func writeSuccessResponseJSON(w http.ResponseWriter, response []byte) {
	writeResponse(w, http.StatusOK, response, mimeJSON)
}

// writeSuccessResponseXML writes success headers and response if any,
// with content-type set to `application/xml`.

	}
	const payloadSize = 512
	rng := rand.New(rand.NewSource(time.Now().UnixNano()))
	payload := make([]byte, payloadSize)
	_, err = rng.Read(payload)
	errFatal(err)

	// Wait for all to connect
	// Parallel writes per server.
	b.Run("bytes", func(b *testing.B) {
		for par := 1; par <= 32; par *= 2 {
			b.Run("par="+strconv.Itoa(par*runtime.GOMAXPROCS(0)), func(b *testing.B) {
				defer timeout(60 * time.Second)()

package cmd

import (
	"os"
)

var (
	// Disallow updating access times
	readMode = os.O_RDONLY | 0x40000 // O_NOATIME

	// Write with data sync only used only for `xl.meta` writes
	writeMode = 0x1000 // O_DSYNC

// EncodeMsg implements msgp.Encodable
func (z lockStats) EncodeMsg(en *msgp.Writer) (err error) {
	// map header, size 3
	// write "Total"
	err = en.Append(0x83, 0xa5, 0x54, 0x6f, 0x74, 0x61, 0x6c)
	if err != nil {
		return
	}
	err = en.WriteInt(z.Total)
	if err != nil {
		err = msgp.WrapError(err, "Total")
		return
	}
	// write "Writes"
	err = en.Append(0xa6, 0x57, 0x72, 0x69, 0x74, 0x65, 0x73)
	if err != nil {

![quota](https://raw.githubusercontent.com/minio/minio/master/docs/bucket/quota/bucketquota.png)

Buckets can be configured to have `Hard` quota - it disallows writes to the bucket after configured quota limit is reached.

## Prerequisites

- Install MinIO - [MinIO Quickstart Guide](https://min.io/docs/minio/linux/index.html#procedure).

	// iostat related
	driveReadsPerSec    = "reads_per_sec"
	driveReadsKBPerSec  = "reads_kb_per_sec"
	driveReadsAwait     = "reads_await"
	driveWritesPerSec   = "writes_per_sec"
	driveWritesKBPerSec = "writes_kb_per_sec"
	driveWritesAwait    = "writes_await"
	drivePercUtil       = "perc_util"
)

var (
	driveUsedBytesMD = NewGaugeMD(driveUsedBytes,
		"Total storage used on a drive in bytes", allDriveLabels...)

package cmd

import (
	"context"
	"encoding/xml"
	"net/http"

	xhttp "github.com/minio/minio/internal/http"
	"github.com/minio/minio/internal/logger"
)

// writeSTSErrorResponse writes error headers
func writeSTSErrorResponse(ctx context.Context, w http.ResponseWriter, errCode STSErrorCode, err error) {
	stsErr := stsErrCodes.ToSTSErr(errCode)

	// Generate error response.

			Optional:    true,
			Type:        "duration",
		},
		config.HelpKV{
			Key:         apiODirect,
			Description: "set to enable or disable O_DIRECT for writes under special conditions. NOTE: do not disable O_DIRECT without prior testing" + defaultHelpPostfix(apiODirect),
			Optional:    true,
			Type:        "boolean",
		},
		config.HelpKV{
			Key:         apiRootAccess,

If one or more drives are offline at the start of a PutObject or NewMultipartUpload operation the object will have additional data
protection bits added automatically to provide the regular safety for these objects up to 50% of the number of drives.
This will allow normal write operations to take place on systems that exceed the write tolerance.