Merge pull request #8447 from filecoin-project/feat/sched-better

feat: sched: Improve worker assigning logic

extern/sector-storage/sched.go

@@ -2,6 +2,7 @@ package sectorstorage
 
 import (
 	"context"
+	"math"
 	"math/rand"
 	"sort"
 	"sync"
@@ -76,6 +77,10 @@ type scheduler struct {
 type workerHandle struct {
 	workerRpc Worker
 
+	tasksCache  map[sealtasks.TaskType]struct{}
+	tasksUpdate time.Time
+	tasksLk     sync.Mutex
+
 	info storiface.WorkerInfo
 
 	preparing *activeResources // use with workerHandle.lk
@@ -361,7 +366,7 @@ func (sh *scheduler) trySched() {
 	}
 
 	windows := make([]schedWindow, windowsLen)
-	acceptableWindows := make([][]int, queueLen)
+	acceptableWindows := make([][]int, queueLen) // QueueIndex -> []OpenWindowIndex
 
 	// Step 1
 	throttle := make(chan struct{}, windowsLen)
@@ -455,41 +460,73 @@ func (sh *scheduler) trySched() {
 	// Step 2
 	scheduled := 0
 	rmQueue := make([]int, 0, queueLen)
+	workerUtil := map[storiface.WorkerID]float64{}
 
 	for sqi := 0; sqi < queueLen; sqi++ {
 		task := (*sh.schedQueue)[sqi]
 
 		selectedWindow := -1
-		for _, wnd := range acceptableWindows[task.indexHeap] {
+		var needRes storiface.Resources
+		var info storiface.WorkerInfo
+		var bestWid storiface.WorkerID
+		bestUtilization := math.MaxFloat64 // smaller = better
+
+		for i, wnd := range acceptableWindows[task.indexHeap] {
 			wid := sh.openWindows[wnd].worker
-			info := sh.workers[wid].info
+			w := sh.workers[wid]
 
-			log.Debugf("SCHED try assign sqi:%d sector %d to window %d", sqi, task.sector.ID.Number, wnd)
+			res := info.Resources.ResourceSpec(task.sector.ProofType, task.taskType)
 
-			needRes := info.Resources.ResourceSpec(task.sector.ProofType, task.taskType)
+			log.Debugf("SCHED try assign sqi:%d sector %d to window %d (awi:%d)", sqi, task.sector.ID.Number, wnd, i)
 
 			// TODO: allow bigger windows
 			if !windows[wnd].allocated.canHandleRequest(needRes, wid, "schedAssign", info) {
 				continue
 			}
 
-			log.Debugf("SCHED ASSIGNED sqi:%d sector %d task %s to window %d", sqi, task.sector.ID.Number, task.taskType, wnd)
-
-			windows[wnd].allocated.add(info.Resources, needRes)
-			// TODO: We probably want to re-sort acceptableWindows here based on new
-			//  workerHandle.utilization + windows[wnd].allocated.utilization (workerHandle.utilization is used in all
-			//  task selectors, but not in the same way, so need to figure out how to do that in a non-O(n^2 way), and
-			//  without additional network roundtrips (O(n^2) could be avoided by turning acceptableWindows.[] into heaps))
+			wu, found := workerUtil[wid]
+			if !found {
+				wu = w.utilization()
+				workerUtil[wid] = wu
+			}
+			if wu >= bestUtilization {
+				// acceptable worker list is initially sorted by utilization, and the initially-best workers
+				// will be assigned tasks first. This means that if we find a worker which isn't better, it
+				// probably means that the other workers aren't better either.
+				//
+				// utilization
+				// ^
+				// |       /
+				// | \    /
+				// |  \  /
+				// |   *
+				// #--------> acceptableWindow index
+				//
+				// * -> we're here
+				break
+			}
 
+			info = w.info
+			needRes = res
+			bestWid = wid
 			selectedWindow = wnd
-			break
+			bestUtilization = wu
 		}
 
 		if selectedWindow < 0 {
 			// all windows full
 			continue
 		}
 
+		log.Debugw("SCHED ASSIGNED",
+			"sqi", sqi,
+			"sector", task.sector.ID.Number,
+			"task", task.taskType,
+			"window", selectedWindow,
+			"worker", bestWid,
+			"utilization", bestUtilization)
+
+		workerUtil[bestWid] += windows[selectedWindow].allocated.add(info.Resources, needRes)
 		windows[selectedWindow].todo = append(windows[selectedWindow].todo, task)
 
 		rmQueue = append(rmQueue, sqi)

extern/sector-storage/sched_resources.go

@@ -1,8 +1,11 @@
 package sectorstorage
 
 import (
+	"context"
 	"sync"
+	"time"
 
+	"github.com/filecoin-project/lotus/extern/sector-storage/sealtasks"
 	"github.com/filecoin-project/lotus/extern/sector-storage/storiface"
 )
 
@@ -30,13 +33,18 @@ func (a *activeResources) hasWorkWaiting() bool {
 	return a.waiting > 0
 }
 
-func (a *activeResources) add(wr storiface.WorkerResources, r storiface.Resources) {
+// add task resources to activeResources and return utilization difference
+func (a *activeResources) add(wr storiface.WorkerResources, r storiface.Resources) float64 {
+	startUtil := a.utilization(wr)
+
 	if r.GPUUtilization > 0 {
 		a.gpuUsed += r.GPUUtilization
 	}
 	a.cpuUse += r.Threads(wr.CPUs, len(wr.GPUs))
 	a.memUsedMin += r.MinMemory
 	a.memUsedMax += r.MaxMemory
+
+	return a.utilization(wr) - startUtil
 }
 
 func (a *activeResources) free(wr storiface.WorkerResources, r storiface.Resources) {
@@ -101,6 +109,7 @@ func (a *activeResources) canHandleRequest(needRes storiface.Resources, wid stor
 	return true
 }
 
+// utilization returns a number in 0..1 range indicating fraction of used resources
 func (a *activeResources) utilization(wr storiface.WorkerResources) float64 {
 	var max float64
 
@@ -126,6 +135,13 @@ func (a *activeResources) utilization(wr storiface.WorkerResources) float64 {
 		max = memMax
 	}
 
+	if len(wr.GPUs) > 0 {
+		gpuMax := a.gpuUsed / float64(len(wr.GPUs))
+		if gpuMax > max {
+			max = gpuMax
+		}
+	}
+
 	return max
 }
 
@@ -142,3 +158,20 @@ func (wh *workerHandle) utilization() float64 {
 
 	return u
 }
+
+var tasksCacheTimeout = 30 * time.Second
+
+func (wh *workerHandle) TaskTypes(ctx context.Context) (t map[sealtasks.TaskType]struct{}, err error) {
+	wh.tasksLk.Lock()
+	defer wh.tasksLk.Unlock()
+
+	if wh.tasksCache == nil || time.Now().Sub(wh.tasksUpdate) > tasksCacheTimeout {
+		wh.tasksCache, err = wh.workerRpc.TaskTypes(ctx)
+		if err != nil {
+			return nil, err
+		}
+		wh.tasksUpdate = time.Now()
+	}
+
+	return wh.tasksCache, nil
+}

extern/sector-storage/selector_alloc.go

@@ -27,7 +27,7 @@ func newAllocSelector(index stores.SectorIndex, alloc storiface.SectorFileType,
 }
 
 func (s *allocSelector) Ok(ctx context.Context, task sealtasks.TaskType, spt abi.RegisteredSealProof, whnd *workerHandle) (bool, error) {
-	tasks, err := whnd.workerRpc.TaskTypes(ctx)
+	tasks, err := whnd.TaskTypes(ctx)
 	if err != nil {
 		return false, xerrors.Errorf("getting supported worker task types: %w", err)
 	}

extern/sector-storage/selector_existing.go

@@ -29,7 +29,7 @@ func newExistingSelector(index stores.SectorIndex, sector abi.SectorID, alloc st
 }
 
 func (s *existingSelector) Ok(ctx context.Context, task sealtasks.TaskType, spt abi.RegisteredSealProof, whnd *workerHandle) (bool, error) {
-	tasks, err := whnd.workerRpc.TaskTypes(ctx)
+	tasks, err := whnd.TaskTypes(ctx)
 	if err != nil {
 		return false, xerrors.Errorf("getting supported worker task types: %w", err)
 	}

extern/sector-storage/selector_task.go

@@ -20,7 +20,7 @@ func newTaskSelector() *taskSelector {
 }
 
 func (s *taskSelector) Ok(ctx context.Context, task sealtasks.TaskType, spt abi.RegisteredSealProof, whnd *workerHandle) (bool, error) {
-	tasks, err := whnd.workerRpc.TaskTypes(ctx)
+	tasks, err := whnd.TaskTypes(ctx)
 	if err != nil {
 		return false, xerrors.Errorf("getting supported worker task types: %w", err)
 	}
@@ -30,11 +30,12 @@ func (s *taskSelector) Ok(ctx context.Context, task sealtasks.TaskType, spt abi.
 }
 
 func (s *taskSelector) Cmp(ctx context.Context, _ sealtasks.TaskType, a, b *workerHandle) (bool, error) {
-	atasks, err := a.workerRpc.TaskTypes(ctx)
+	atasks, err := a.TaskTypes(ctx)
 	if err != nil {
 		return false, xerrors.Errorf("getting supported worker task types: %w", err)
 	}
-	btasks, err := b.workerRpc.TaskTypes(ctx)
+
+	btasks, err := b.TaskTypes(ctx)
 	if err != nil {
 		return false, xerrors.Errorf("getting supported worker task types: %w", err)
 	}