package sectorstorage import ( "context" "time" "golang.org/x/xerrors" "github.com/filecoin-project/lotus/extern/sector-storage/stores" ) type schedWorker struct { sched *scheduler worker *workerHandle wid WorkerID heartbeatTimer *time.Ticker scheduledWindows chan *schedWindow taskDone chan struct{} windowsRequested int } // context only used for startup func (sh *scheduler) runWorker(ctx context.Context, w Worker) error { info, err := w.Info(ctx) if err != nil { return xerrors.Errorf("getting worker info: %w", err) } sessID, err := w.Session(ctx) if err != nil { return xerrors.Errorf("getting worker session: %w", err) } if sessID == ClosedWorkerID { return xerrors.Errorf("worker already closed") } worker := &workerHandle{ workerRpc: w, info: info, preparing: &activeResources{}, active: &activeResources{}, enabled: true, closingMgr: make(chan struct{}), closedMgr: make(chan struct{}), } wid := WorkerID(sessID) sh.workersLk.Lock() _, exist := sh.workers[wid] if exist { log.Warnw("duplicated worker added", "id", wid) // this is ok, we're already handling this worker in a different goroutine sh.workersLk.Unlock() return nil } sh.workers[wid] = worker sh.workersLk.Unlock() sw := &schedWorker{ sched: sh, worker: worker, wid: wid, heartbeatTimer: time.NewTicker(stores.HeartbeatInterval), scheduledWindows: make(chan *schedWindow, SchedWindows), taskDone: make(chan struct{}, 1), windowsRequested: 0, } go sw.handleWorker() return nil } func (sw *schedWorker) handleWorker() { worker, sched := sw.worker, sw.sched ctx, cancel := context.WithCancel(context.TODO()) defer cancel() defer close(worker.closedMgr) defer func() { log.Warnw("Worker closing", "workerid", sw.wid) if err := sw.disable(ctx); err != nil { log.Warnw("failed to disable worker", "worker", sw.wid, "error", err) } sched.workersLk.Lock() delete(sched.workers, sw.wid) sched.workersLk.Unlock() }() defer sw.heartbeatTimer.Stop() for { { sched.workersLk.Lock() enabled := worker.enabled sched.workersLk.Unlock() // ask for more windows if we need them (non-blocking) if enabled { if !sw.requestWindows() { return // graceful shutdown } } } // wait for more windows to come in, or for tasks to get finished (blocking) for { // ping the worker and check session if !sw.checkSession(ctx) { return // invalid session / exiting } // session looks good { sched.workersLk.Lock() enabled := worker.enabled worker.enabled = true sched.workersLk.Unlock() if !enabled { // go send window requests break } } // wait for more tasks to be assigned by the main scheduler or for the worker // to finish precessing a task update, pokeSched, ok := sw.waitForUpdates() if !ok { return } if pokeSched { // a task has finished preparing, which can mean that we've freed some space on some worker select { case sched.workerChange <- struct{}{}: default: // workerChange is buffered, and scheduling is global, so it's ok if we don't send here } } if update { break } } // process assigned windows (non-blocking) sched.workersLk.RLock() worker.wndLk.Lock() sw.workerCompactWindows() // send tasks to the worker sw.processAssignedWindows() worker.wndLk.Unlock() sched.workersLk.RUnlock() } } func (sw *schedWorker) disable(ctx context.Context) error { done := make(chan struct{}) // request cleanup in the main scheduler goroutine select { case sw.sched.workerDisable <- workerDisableReq{ activeWindows: sw.worker.activeWindows, wid: sw.wid, done: func() { close(done) }, }: case <-ctx.Done(): return ctx.Err() case <-sw.sched.closing: return nil } // wait for cleanup to complete select { case <-done: case <-ctx.Done(): return ctx.Err() case <-sw.sched.closing: return nil } sw.worker.activeWindows = sw.worker.activeWindows[:0] sw.windowsRequested = 0 return nil } func (sw *schedWorker) checkSession(ctx context.Context) bool { for { sctx, scancel := context.WithTimeout(ctx, stores.HeartbeatInterval/2) curSes, err := sw.worker.workerRpc.Session(sctx) scancel() if err != nil { // Likely temporary error log.Warnw("failed to check worker session", "error", err) if err := sw.disable(ctx); err != nil { log.Warnw("failed to disable worker with session error", "worker", sw.wid, "error", err) } select { case <-sw.heartbeatTimer.C: continue case w := <-sw.scheduledWindows: // was in flight when initially disabled, return sw.worker.wndLk.Lock() sw.worker.activeWindows = append(sw.worker.activeWindows, w) sw.worker.wndLk.Unlock() if err := sw.disable(ctx); err != nil { log.Warnw("failed to disable worker with session error", "worker", sw.wid, "error", err) } case <-sw.sched.closing: return false case <-sw.worker.closingMgr: return false } continue } if WorkerID(curSes) != sw.wid { if curSes != ClosedWorkerID { // worker restarted log.Warnw("worker session changed (worker restarted?)", "initial", sw.wid, "current", curSes) } return false } return true } } func (sw *schedWorker) requestWindows() bool { for ; sw.windowsRequested < SchedWindows; sw.windowsRequested++ { select { case sw.sched.windowRequests <- &schedWindowRequest{ worker: sw.wid, done: sw.scheduledWindows, }: case <-sw.sched.closing: return false case <-sw.worker.closingMgr: return false } } return true } func (sw *schedWorker) waitForUpdates() (update bool, sched bool, ok bool) { select { case <-sw.heartbeatTimer.C: return false, false, true case w := <-sw.scheduledWindows: sw.worker.wndLk.Lock() sw.worker.activeWindows = append(sw.worker.activeWindows, w) sw.worker.wndLk.Unlock() return true, false, true case <-sw.taskDone: log.Debugw("task done", "workerid", sw.wid) return true, true, true case <-sw.sched.closing: case <-sw.worker.closingMgr: } return false, false, false } func (sw *schedWorker) workerCompactWindows() { worker := sw.worker // move tasks from older windows to newer windows if older windows // still can fit them if len(worker.activeWindows) > 1 { for wi, window := range worker.activeWindows[1:] { lower := worker.activeWindows[wi] var moved []int for ti, todo := range window.todo { needRes := ResourceTable[todo.taskType][todo.sector.ProofType] if !lower.allocated.canHandleRequest(needRes, sw.wid, "compactWindows", worker.info.Resources) { continue } moved = append(moved, ti) lower.todo = append(lower.todo, todo) lower.allocated.add(worker.info.Resources, needRes) window.allocated.free(worker.info.Resources, needRes) } if len(moved) > 0 { newTodo := make([]*workerRequest, 0, len(window.todo)-len(moved)) for i, t := range window.todo { if len(moved) > 0 && moved[0] == i { moved = moved[1:] continue } newTodo = append(newTodo, t) } window.todo = newTodo } } } var compacted int var newWindows []*schedWindow for _, window := range worker.activeWindows { if len(window.todo) == 0 { compacted++ continue } newWindows = append(newWindows, window) } worker.activeWindows = newWindows sw.windowsRequested -= compacted } func (sw *schedWorker) processAssignedWindows() { worker := sw.worker assignLoop: // process windows in order for len(worker.activeWindows) > 0 { firstWindow := worker.activeWindows[0] // process tasks within a window, preferring tasks at lower indexes for len(firstWindow.todo) > 0 { tidx := -1 worker.lk.Lock() for t, todo := range firstWindow.todo { needRes := ResourceTable[todo.taskType][todo.sector.ProofType] if worker.preparing.canHandleRequest(needRes, sw.wid, "startPreparing", worker.info.Resources) { tidx = t break } } worker.lk.Unlock() if tidx == -1 { break assignLoop } todo := firstWindow.todo[tidx] log.Debugf("assign worker sector %d", todo.sector.ID.Number) err := sw.startProcessingTask(sw.taskDone, todo) if err != nil { log.Errorf("startProcessingTask error: %+v", err) go todo.respond(xerrors.Errorf("startProcessingTask error: %w", err)) } // Note: we're not freeing window.allocated resources here very much on purpose copy(firstWindow.todo[tidx:], firstWindow.todo[tidx+1:]) firstWindow.todo[len(firstWindow.todo)-1] = nil firstWindow.todo = firstWindow.todo[:len(firstWindow.todo)-1] } copy(worker.activeWindows, worker.activeWindows[1:]) worker.activeWindows[len(worker.activeWindows)-1] = nil worker.activeWindows = worker.activeWindows[:len(worker.activeWindows)-1] sw.windowsRequested-- } } func (sw *schedWorker) startProcessingTask(taskDone chan struct{}, req *workerRequest) error { w, sh := sw.worker, sw.sched needRes := ResourceTable[req.taskType][req.sector.ProofType] w.lk.Lock() w.preparing.add(w.info.Resources, needRes) w.lk.Unlock() go func() { // first run the prepare step (e.g. fetching sector data from other worker) err := req.prepare(req.ctx, sh.workTracker.worker(sw.wid, w.info, w.workerRpc)) sh.workersLk.Lock() if err != nil { w.lk.Lock() w.preparing.free(w.info.Resources, needRes) w.lk.Unlock() sh.workersLk.Unlock() select { case taskDone <- struct{}{}: case <-sh.closing: log.Warnf("scheduler closed while sending response (prepare error: %+v)", err) } select { case req.ret <- workerResponse{err: err}: case <-req.ctx.Done(): log.Warnf("request got cancelled before we could respond (prepare error: %+v)", err) case <-sh.closing: log.Warnf("scheduler closed while sending response (prepare error: %+v)", err) } return } // wait (if needed) for resources in the 'active' window err = w.active.withResources(sw.wid, w.info.Resources, needRes, &sh.workersLk, func() error { w.lk.Lock() w.preparing.free(w.info.Resources, needRes) w.lk.Unlock() sh.workersLk.Unlock() defer sh.workersLk.Lock() // we MUST return locked from this function select { case taskDone <- struct{}{}: case <-sh.closing: } // Do the work! err = req.work(req.ctx, sh.workTracker.worker(sw.wid, w.info, w.workerRpc)) select { case req.ret <- workerResponse{err: err}: case <-req.ctx.Done(): log.Warnf("request got cancelled before we could respond") case <-sh.closing: log.Warnf("scheduler closed while sending response") } return nil }) sh.workersLk.Unlock() // This error should always be nil, since nothing is setting it, but just to be safe: if err != nil { log.Errorf("error executing worker (withResources): %+v", err) } }() return nil } func (sh *scheduler) workerCleanup(wid WorkerID, w *workerHandle) { select { case <-w.closingMgr: default: close(w.closingMgr) } sh.workersLk.Unlock() select { case <-w.closedMgr: case <-time.After(time.Second): log.Errorf("timeout closing worker manager goroutine %d", wid) } sh.workersLk.Lock() if !w.cleanupStarted { w.cleanupStarted = true newWindows := make([]*schedWindowRequest, 0, len(sh.openWindows)) for _, window := range sh.openWindows { if window.worker != wid { newWindows = append(newWindows, window) } } sh.openWindows = newWindows log.Debugf("worker %s dropped", wid) } }