frostfs-s3-gw/legacy/data-update-tracker.go
2020-07-09 12:28:51 +03:00

620 lines
15 KiB
Go

/*
* MinIO Cloud Storage, (C) 2020 MinIO, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package legacy
import (
"bufio"
"bytes"
"context"
"encoding/binary"
"errors"
"io"
"io/ioutil"
"os"
"path"
"sort"
"strings"
"sync"
"time"
"github.com/minio/minio/legacy/config"
"github.com/minio/minio/legacy/logger"
"github.com/minio/minio/pkg/color"
"github.com/minio/minio/pkg/env"
"github.com/willf/bloom"
)
const (
// Estimate bloom filter size. With this many items
dataUpdateTrackerEstItems = 1000000
// ... we want this false positive rate:
dataUpdateTrackerFP = 0.99
dataUpdateTrackerQueueSize = 10000
dataUpdateTrackerFilename = dataUsageBucket + SlashSeparator + ".tracker.bin"
dataUpdateTrackerVersion = 2
dataUpdateTrackerSaveInterval = 5 * time.Minute
// Reset bloom filters every n cycle
dataUpdateTrackerResetEvery = 1000
)
var (
objectUpdatedCh chan<- string
intDataUpdateTracker *dataUpdateTracker
)
func init() {
intDataUpdateTracker = newDataUpdateTracker()
objectUpdatedCh = intDataUpdateTracker.input
}
type dataUpdateTracker struct {
mu sync.Mutex
input chan string
save chan struct{}
debug bool
saveExited chan struct{}
dirty bool
Current dataUpdateFilter
History dataUpdateTrackerHistory
Saved time.Time
}
// newDataUpdateTracker returns a dataUpdateTracker with default settings.
func newDataUpdateTracker() *dataUpdateTracker {
d := &dataUpdateTracker{
Current: dataUpdateFilter{
idx: 1,
},
debug: env.Get(envDataUsageCrawlDebug, config.EnableOff) == config.EnableOn,
input: make(chan string, dataUpdateTrackerQueueSize),
save: make(chan struct{}, 1),
saveExited: make(chan struct{}),
}
d.Current.bf = d.newBloomFilter()
d.dirty = true
return d
}
type dataUpdateTrackerHistory []dataUpdateFilter
type dataUpdateFilter struct {
idx uint64
bf bloomFilter
}
type bloomFilter struct {
*bloom.BloomFilter
}
// emptyBloomFilter returns an empty bloom filter.
func emptyBloomFilter() bloomFilter {
return bloomFilter{BloomFilter: &bloom.BloomFilter{}}
}
// containsDir returns whether the bloom filter contains a directory.
// Note that objects in XL mode are also considered directories.
func (b bloomFilter) containsDir(in string) bool {
split := splitPathDeterministic(path.Clean(in))
if len(split) == 0 {
return false
}
return b.TestString(hashPath(path.Join(split...)).String())
}
// bytes returns the bloom filter serialized as a byte slice.
func (b bloomFilter) bytes() []byte {
if b.BloomFilter == nil {
return nil
}
var buf bytes.Buffer
_, err := b.WriteTo(&buf)
if err != nil {
logger.LogIf(GlobalContext, err)
return nil
}
return buf.Bytes()
}
// sort the dataUpdateTrackerHistory, newest first.
// Returns whether the history is complete.
func (d dataUpdateTrackerHistory) sort() bool {
if len(d) == 0 {
return true
}
sort.Slice(d, func(i, j int) bool {
return d[i].idx > d[j].idx
})
return d[0].idx-d[len(d)-1].idx == uint64(len(d))
}
// removeOlderThan will remove entries older than index 'n'.
func (d *dataUpdateTrackerHistory) removeOlderThan(n uint64) {
d.sort()
dd := *d
end := len(dd)
for i := end - 1; i >= 0; i-- {
if dd[i].idx < n {
end = i
}
}
dd = dd[:end]
*d = dd
}
// newBloomFilter returns a new bloom filter with default settings.
func (d *dataUpdateTracker) newBloomFilter() bloomFilter {
return bloomFilter{bloom.NewWithEstimates(dataUpdateTrackerEstItems, dataUpdateTrackerFP)}
}
// current returns the current index.
func (d *dataUpdateTracker) current() uint64 {
d.mu.Lock()
defer d.mu.Unlock()
return d.Current.idx
}
// start will load the current data from the drives start collecting information and
// start a saver goroutine.
// All of these will exit when the context is canceled.
func (d *dataUpdateTracker) start(ctx context.Context, drives ...string) {
if len(drives) <= 0 {
logger.LogIf(ctx, errors.New("dataUpdateTracker.start: No drives specified"))
return
}
d.load(ctx, drives...)
go d.startCollector(ctx)
go d.startSaver(ctx, dataUpdateTrackerSaveInterval, drives)
}
// load will attempt to load data tracking information from the supplied drives.
// The data will only be loaded if d.Saved is older than the one found on disk.
// The newest working cache will be kept in d.
// If no valid data usage tracker can be found d will remain unchanged.
// If object is shared the caller should lock it.
func (d *dataUpdateTracker) load(ctx context.Context, drives ...string) {
if len(drives) <= 0 {
logger.LogIf(ctx, errors.New("dataUpdateTracker.load: No drives specified"))
return
}
for _, drive := range drives {
cacheFormatPath := pathJoin(drive, dataUpdateTrackerFilename)
f, err := os.Open(cacheFormatPath)
if err != nil {
if os.IsNotExist(err) {
continue
}
logger.LogIf(ctx, err)
continue
}
err = d.deserialize(f, d.Saved)
if err != nil && err != io.EOF {
logger.LogIf(ctx, err)
}
f.Close()
}
}
// startSaver will start a saver that will write d to all supplied drives at specific intervals.
// The saver will save and exit when supplied context is closed.
func (d *dataUpdateTracker) startSaver(ctx context.Context, interval time.Duration, drives []string) {
t := time.NewTicker(interval)
defer t.Stop()
var buf bytes.Buffer
d.mu.Lock()
saveNow := d.save
exited := make(chan struct{})
d.saveExited = exited
d.mu.Unlock()
defer close(exited)
for {
var exit bool
select {
case <-ctx.Done():
exit = true
case <-t.C:
case <-saveNow:
}
buf.Reset()
d.mu.Lock()
if !d.dirty {
d.mu.Unlock()
return
}
d.Saved = UTCNow()
err := d.serialize(&buf)
if d.debug {
logger.Info(color.Green("dataUpdateTracker:")+" Saving: %v bytes, Current idx: %v", buf.Len(), d.Current.idx)
}
d.dirty = false
d.mu.Unlock()
if err != nil {
logger.LogIf(ctx, err, "Error serializing usage tracker data")
if exit {
return
}
continue
}
if buf.Len() == 0 {
logger.LogIf(ctx, errors.New("zero sized output, skipping save"))
continue
}
for _, drive := range drives {
cacheFormatPath := pathJoin(drive, dataUpdateTrackerFilename)
err := ioutil.WriteFile(cacheFormatPath, buf.Bytes(), os.ModePerm)
if err != nil {
if os.IsNotExist(err) {
continue
}
logger.LogIf(ctx, err)
continue
}
}
if exit {
return
}
}
}
// serialize all data in d to dst.
// Caller should hold lock if d is expected to be shared.
// If an error is returned, there will likely be partial data written to dst.
func (d *dataUpdateTracker) serialize(dst io.Writer) (err error) {
ctx := GlobalContext
var tmp [8]byte
o := bufio.NewWriter(dst)
defer func() {
if err == nil {
err = o.Flush()
}
}()
// Version
if err := o.WriteByte(dataUpdateTrackerVersion); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
// Timestamp.
binary.LittleEndian.PutUint64(tmp[:], uint64(d.Saved.Unix()))
if _, err := o.Write(tmp[:]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
// Current
binary.LittleEndian.PutUint64(tmp[:], d.Current.idx)
if _, err := o.Write(tmp[:]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
if _, err := d.Current.bf.WriteTo(o); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
// History
binary.LittleEndian.PutUint64(tmp[:], uint64(len(d.History)))
if _, err := o.Write(tmp[:]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
for _, bf := range d.History {
// Current
binary.LittleEndian.PutUint64(tmp[:], bf.idx)
if _, err := o.Write(tmp[:]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
if _, err := bf.bf.WriteTo(o); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
}
return nil
}
// deserialize will deserialize the supplied input if the input is newer than the supplied time.
func (d *dataUpdateTracker) deserialize(src io.Reader, newerThan time.Time) error {
ctx := GlobalContext
var dst dataUpdateTracker
var tmp [8]byte
// Version
if _, err := io.ReadFull(src, tmp[:1]); err != nil {
if d.debug {
if err != io.EOF {
logger.LogIf(ctx, err)
}
}
return err
}
switch tmp[0] {
case 1:
logger.Info(color.Green("dataUpdateTracker: ") + "deprecated data version, updating.")
return nil
case dataUpdateTrackerVersion:
default:
return errors.New("dataUpdateTracker: Unknown data version")
}
// Timestamp.
if _, err := io.ReadFull(src, tmp[:8]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
t := time.Unix(int64(binary.LittleEndian.Uint64(tmp[:])), 0)
if !t.After(newerThan) {
return nil
}
// Current
if _, err := io.ReadFull(src, tmp[:8]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
dst.Current.idx = binary.LittleEndian.Uint64(tmp[:])
dst.Current.bf = emptyBloomFilter()
if _, err := dst.Current.bf.ReadFrom(src); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
// History
if _, err := io.ReadFull(src, tmp[:8]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
n := binary.LittleEndian.Uint64(tmp[:])
dst.History = make(dataUpdateTrackerHistory, int(n))
for i, e := range dst.History {
if _, err := io.ReadFull(src, tmp[:8]); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
e.idx = binary.LittleEndian.Uint64(tmp[:])
e.bf = emptyBloomFilter()
if _, err := e.bf.ReadFrom(src); err != nil {
if d.debug {
logger.LogIf(ctx, err)
}
return err
}
dst.History[i] = e
}
// Ignore what remains on the stream.
// Update d:
d.Current = dst.Current
d.History = dst.History
d.Saved = dst.Saved
return nil
}
// start a collector that picks up entries from objectUpdatedCh
// and adds them to the current bloom filter.
func (d *dataUpdateTracker) startCollector(ctx context.Context) {
for {
select {
case <-ctx.Done():
return
case in := <-d.input:
bucket, _ := path2BucketObjectWithBasePath("", in)
if bucket == "" {
if d.debug && len(in) > 0 {
logger.Info(color.Green("data-usage:")+" no bucket (%s)", in)
}
continue
}
if isReservedOrInvalidBucket(bucket, false) {
if false && d.debug {
logger.Info(color.Green("data-usage:")+" isReservedOrInvalidBucket: %v, entry: %v", bucket, in)
}
continue
}
split := splitPathDeterministic(in)
// Add all paths until level 3.
d.mu.Lock()
for i := range split {
if d.debug && false {
logger.Info(color.Green("dataUpdateTracker:") + " Marking path dirty: " + color.Blue(path.Join(split[:i+1]...)))
}
d.Current.bf.AddString(hashPath(path.Join(split[:i+1]...)).String())
}
d.dirty = d.dirty || len(split) > 0
d.mu.Unlock()
}
}
}
// find entry with specified index.
// Returns nil if not found.
func (d dataUpdateTrackerHistory) find(idx uint64) *dataUpdateFilter {
for _, f := range d {
if f.idx == idx {
return &f
}
}
return nil
}
// filterFrom will return a combined bloom filter.
func (d *dataUpdateTracker) filterFrom(ctx context.Context, oldest, newest uint64) *bloomFilterResponse {
bf := d.newBloomFilter()
bfr := bloomFilterResponse{
OldestIdx: oldest,
CurrentIdx: d.Current.idx,
Complete: true,
}
// Loop through each index requested.
for idx := oldest; idx <= newest; idx++ {
v := d.History.find(idx)
if v == nil {
if d.Current.idx == idx {
// Merge current.
err := bf.Merge(d.Current.bf.BloomFilter)
logger.LogIf(ctx, err)
if err != nil {
bfr.Complete = false
}
continue
}
bfr.Complete = false
bfr.OldestIdx = idx + 1
continue
}
err := bf.Merge(v.bf.BloomFilter)
if err != nil {
bfr.Complete = false
logger.LogIf(ctx, err)
continue
}
bfr.NewestIdx = idx
}
var dst bytes.Buffer
_, err := bf.WriteTo(&dst)
if err != nil {
logger.LogIf(ctx, err)
return nil
}
bfr.Filter = dst.Bytes()
return &bfr
}
// cycleFilter will cycle the bloom filter to start recording to index y if not already.
// The response will contain a bloom filter starting at index x up to, but not including index y.
// If y is 0, the response will not update y, but return the currently recorded information
// from the up until and including current y.
func (d *dataUpdateTracker) cycleFilter(ctx context.Context, oldest, current uint64) (*bloomFilterResponse, error) {
d.mu.Lock()
defer d.mu.Unlock()
if current == 0 {
if len(d.History) == 0 {
return d.filterFrom(ctx, d.Current.idx, d.Current.idx), nil
}
d.History.sort()
return d.filterFrom(ctx, d.History[len(d.History)-1].idx, d.Current.idx), nil
}
// Move current to history if new one requested
if d.Current.idx != current {
d.dirty = true
if d.debug {
logger.Info(color.Green("dataUpdateTracker:")+" cycle bloom filter: %v -> %v", d.Current.idx, current)
}
d.History = append(d.History, d.Current)
d.Current.idx = current
d.Current.bf = d.newBloomFilter()
select {
case d.save <- struct{}{}:
default:
}
}
d.History.removeOlderThan(oldest)
return d.filterFrom(ctx, oldest, current), nil
}
// splitPathDeterministic will split the provided relative path
// deterministically and return up to the first 3 elements of the path.
// Slash and dot prefixes are removed.
// Trailing slashes are removed.
// Returns 0 length if no parts are found after trimming.
func splitPathDeterministic(in string) []string {
split := strings.Split(in, SlashSeparator)
// Trim empty start/end
for len(split) > 0 {
if len(split[0]) > 0 && split[0] != "." {
break
}
split = split[1:]
}
for len(split) > 0 {
if len(split[len(split)-1]) > 0 {
break
}
split = split[:len(split)-1]
}
// Return up to 3 parts.
if len(split) > 3 {
split = split[:3]
}
return split
}
// bloomFilterRequest request bloom filters.
// Current index will be updated to current and entries back to Oldest is returned.
type bloomFilterRequest struct {
Oldest uint64
Current uint64
}
type bloomFilterResponse struct {
// Current index being written to.
CurrentIdx uint64
// Oldest index in the returned bloom filter.
OldestIdx uint64
// Newest Index in the returned bloom filter.
NewestIdx uint64
// Are all indexes between oldest and newest filled?
Complete bool
// Binary data of the bloom filter.
Filter []byte
}
// ObjectPathUpdated indicates a path has been updated.
// The function will never block.
func ObjectPathUpdated(s string) {
select {
case objectUpdatedCh <- s:
default:
}
}