syncthing/lib/model/progressemitter.go
Jakob Borg d62a0cf692
lib/model: Handle progress emitter zero interval (fixes #6281) (#6282)
Makes the logic a bit clearer and safer. This also sneakily redefines
the 0 interval to also mean disabled, whereas it previously meant ...
sometimes default to 1s, sometimes just spin.
2020-01-20 21:14:29 +01:00

330 lines
9.5 KiB
Go

// Copyright (C) 2014 The Syncthing Authors.
//
// This Source Code Form is subject to the terms of the Mozilla Public
// License, v. 2.0. If a copy of the MPL was not distributed with this file,
// You can obtain one at https://mozilla.org/MPL/2.0/.
package model
import (
"context"
"fmt"
"time"
"github.com/thejerf/suture"
"github.com/syncthing/syncthing/lib/config"
"github.com/syncthing/syncthing/lib/events"
"github.com/syncthing/syncthing/lib/protocol"
"github.com/syncthing/syncthing/lib/sync"
"github.com/syncthing/syncthing/lib/util"
)
type ProgressEmitter struct {
suture.Service
cfg config.Wrapper
registry map[string]map[string]*sharedPullerState // folder: name: puller
interval time.Duration
minBlocks int
sentDownloadStates map[protocol.DeviceID]*sentDownloadState // States representing what we've sent to the other peer via DownloadProgress messages.
connections map[protocol.DeviceID]protocol.Connection
foldersByConns map[protocol.DeviceID][]string
disabled bool
evLogger events.Logger
mut sync.Mutex
timer *time.Timer
}
// NewProgressEmitter creates a new progress emitter which emits
// DownloadProgress events every interval.
func NewProgressEmitter(cfg config.Wrapper, evLogger events.Logger) *ProgressEmitter {
t := &ProgressEmitter{
cfg: cfg,
registry: make(map[string]map[string]*sharedPullerState),
timer: time.NewTimer(time.Millisecond),
sentDownloadStates: make(map[protocol.DeviceID]*sentDownloadState),
connections: make(map[protocol.DeviceID]protocol.Connection),
foldersByConns: make(map[protocol.DeviceID][]string),
evLogger: evLogger,
mut: sync.NewMutex(),
}
t.Service = util.AsService(t.serve, t.String())
t.CommitConfiguration(config.Configuration{}, cfg.RawCopy())
return t
}
// serve starts the progress emitter which starts emitting DownloadProgress
// events as the progress happens.
func (t *ProgressEmitter) serve(ctx context.Context) {
t.cfg.Subscribe(t)
defer t.cfg.Unsubscribe(t)
var lastUpdate time.Time
var lastCount, newCount int
for {
select {
case <-ctx.Done():
l.Debugln("progress emitter: stopping")
return
case <-t.timer.C:
t.mut.Lock()
l.Debugln("progress emitter: timer - looking after", len(t.registry))
newLastUpdated := lastUpdate
newCount = t.lenRegistryLocked()
for _, pullers := range t.registry {
for _, puller := range pullers {
if updated := puller.Updated(); updated.After(newLastUpdated) {
newLastUpdated = updated
}
}
}
if !newLastUpdated.Equal(lastUpdate) || newCount != lastCount {
lastUpdate = newLastUpdated
lastCount = newCount
t.sendDownloadProgressEventLocked()
if len(t.connections) > 0 {
t.sendDownloadProgressMessagesLocked(ctx)
}
} else {
l.Debugln("progress emitter: nothing new")
}
if newCount != 0 {
t.timer.Reset(t.interval)
}
t.mut.Unlock()
}
}
}
func (t *ProgressEmitter) sendDownloadProgressEventLocked() {
output := make(map[string]map[string]*pullerProgress)
for folder, pullers := range t.registry {
if len(pullers) == 0 {
continue
}
output[folder] = make(map[string]*pullerProgress)
for name, puller := range pullers {
output[folder][name] = puller.Progress()
}
}
t.evLogger.Log(events.DownloadProgress, output)
l.Debugf("progress emitter: emitting %#v", output)
}
func (t *ProgressEmitter) sendDownloadProgressMessagesLocked(ctx context.Context) {
for id, conn := range t.connections {
for _, folder := range t.foldersByConns[id] {
pullers, ok := t.registry[folder]
if !ok {
// There's never been any puller registered for this folder yet
continue
}
state, ok := t.sentDownloadStates[id]
if !ok {
state = &sentDownloadState{
folderStates: make(map[string]*sentFolderDownloadState),
}
t.sentDownloadStates[id] = state
}
activePullers := make([]*sharedPullerState, 0, len(pullers))
for _, puller := range pullers {
if puller.folder != folder || puller.file.IsSymlink() || puller.file.IsDirectory() || len(puller.file.Blocks) <= t.minBlocks {
continue
}
activePullers = append(activePullers, puller)
}
// For every new puller that hasn't yet been seen, it will send all the blocks the puller has available
// For every existing puller, it will check for new blocks, and send update for the new blocks only
// For every puller that we've seen before but is no longer there, we will send a forget message
updates := state.update(folder, activePullers)
if len(updates) > 0 {
conn.DownloadProgress(ctx, folder, updates)
}
}
}
// Clean up sentDownloadStates for devices which we are no longer connected to.
for id := range t.sentDownloadStates {
_, ok := t.connections[id]
if !ok {
// Null out outstanding entries for device
delete(t.sentDownloadStates, id)
}
}
// If a folder was unshared from some device, tell it that all temp files
// are now gone.
for id, state := range t.sentDownloadStates {
// For each of the folders that the state is aware of,
// try to match it with a shared folder we've discovered above,
nextFolder:
for _, folder := range state.folders() {
for _, existingFolder := range t.foldersByConns[id] {
if existingFolder == folder {
continue nextFolder
}
}
// If we fail to find that folder, we tell the state to forget about it
// and return us a list of updates which would clean up the state
// on the remote end.
state.cleanup(folder)
// updates := state.cleanup(folder)
// if len(updates) > 0 {
// XXX: Don't send this now, as the only way we've unshared a folder
// is by breaking the connection and reconnecting, hence sending
// forget messages for some random folder currently makes no sense.
// deviceConns[id].DownloadProgress(folder, updates, 0, nil)
// }
}
}
}
// VerifyConfiguration implements the config.Committer interface
func (t *ProgressEmitter) VerifyConfiguration(from, to config.Configuration) error {
return nil
}
// CommitConfiguration implements the config.Committer interface
func (t *ProgressEmitter) CommitConfiguration(_, to config.Configuration) bool {
t.mut.Lock()
defer t.mut.Unlock()
newInterval := time.Duration(to.Options.ProgressUpdateIntervalS) * time.Second
if newInterval > 0 {
if t.disabled {
t.disabled = false
l.Debugln("progress emitter: enabled")
}
if t.interval != newInterval {
t.interval = newInterval
l.Debugln("progress emitter: updated interval", t.interval)
}
} else if !t.disabled {
t.clearLocked()
t.disabled = true
l.Debugln("progress emitter: disabled")
}
t.minBlocks = to.Options.TempIndexMinBlocks
if t.interval < time.Second {
// can't happen when we're not disabled, but better safe than sorry.
t.interval = time.Second
}
return true
}
// Register a puller with the emitter which will start broadcasting pullers
// progress.
func (t *ProgressEmitter) Register(s *sharedPullerState) {
t.mut.Lock()
defer t.mut.Unlock()
if t.disabled {
l.Debugln("progress emitter: disabled, skip registering")
return
}
l.Debugln("progress emitter: registering", s.folder, s.file.Name)
if t.emptyLocked() {
t.timer.Reset(t.interval)
}
if _, ok := t.registry[s.folder]; !ok {
t.registry[s.folder] = make(map[string]*sharedPullerState)
}
t.registry[s.folder][s.file.Name] = s
}
// Deregister a puller which will stop broadcasting pullers state.
func (t *ProgressEmitter) Deregister(s *sharedPullerState) {
t.mut.Lock()
defer t.mut.Unlock()
if t.disabled {
l.Debugln("progress emitter: disabled, skip deregistering")
return
}
l.Debugln("progress emitter: deregistering", s.folder, s.file.Name)
delete(t.registry[s.folder], s.file.Name)
}
// BytesCompleted returns the number of bytes completed in the given folder.
func (t *ProgressEmitter) BytesCompleted(folder string) (bytes int64) {
t.mut.Lock()
defer t.mut.Unlock()
for _, s := range t.registry[folder] {
bytes += s.Progress().BytesDone
}
l.Debugf("progress emitter: bytes completed for %s: %d", folder, bytes)
return
}
func (t *ProgressEmitter) String() string {
return fmt.Sprintf("ProgressEmitter@%p", t)
}
func (t *ProgressEmitter) lenRegistry() int {
t.mut.Lock()
defer t.mut.Unlock()
return t.lenRegistryLocked()
}
func (t *ProgressEmitter) lenRegistryLocked() (out int) {
for _, pullers := range t.registry {
out += len(pullers)
}
return out
}
func (t *ProgressEmitter) emptyLocked() bool {
for _, pullers := range t.registry {
if len(pullers) != 0 {
return false
}
}
return true
}
func (t *ProgressEmitter) temporaryIndexSubscribe(conn protocol.Connection, folders []string) {
t.mut.Lock()
defer t.mut.Unlock()
t.connections[conn.ID()] = conn
t.foldersByConns[conn.ID()] = folders
}
func (t *ProgressEmitter) temporaryIndexUnsubscribe(conn protocol.Connection) {
t.mut.Lock()
defer t.mut.Unlock()
delete(t.connections, conn.ID())
delete(t.foldersByConns, conn.ID())
}
func (t *ProgressEmitter) clearLocked() {
for id, state := range t.sentDownloadStates {
conn, ok := t.connections[id]
if !ok {
continue
}
for _, folder := range state.folders() {
if updates := state.cleanup(folder); len(updates) > 0 {
conn.DownloadProgress(context.Background(), folder, updates)
}
}
}
t.registry = make(map[string]map[string]*sharedPullerState)
t.sentDownloadStates = make(map[protocol.DeviceID]*sentDownloadState)
t.connections = make(map[protocol.DeviceID]protocol.Connection)
t.foldersByConns = make(map[protocol.DeviceID][]string)
}