diff --git a/pkg/scheduler/framework/statement.go b/pkg/scheduler/framework/statement.go
index 9960820a4..a9527582a 100644
--- a/pkg/scheduler/framework/statement.go
+++ b/pkg/scheduler/framework/statement.go
@@ -35,6 +35,7 @@ import (
 
 type Statement struct {
 	operations []Operation
+	validOps   []bool
 	ssn        *Session
 	sessionID  string
 }
@@ -57,6 +58,7 @@ func (s *Statement) Rollback(cp Checkpoint) error {
 	}
 
 	s.operations = s.operations[:cp]
+	s.validOps = s.validOps[:cp]
 	return nil
 }
 
@@ -116,6 +118,7 @@ func (s *Statement) Evict(reclaimeeTask *pod_info.PodInfo, message string,
 			},
 		},
 	)
+	s.validOps = append(s.validOps, true)
 	reclaimeeTask.IsVirtualStatus = true
 
 	log.InfraLogger.V(6).Infof("Statement evicted task: <%v/%v> from node: <%v>",
@@ -284,6 +287,7 @@ func (s *Statement) Pipeline(task *pod_info.PodInfo, hostname string, updateTask
 			return s.unpipeline(task, previousNode, previousStatus, previousGpuGroup, previousResourceClaimInfo, previousIsVirtualStatus)
 		},
 	})
+	s.validOps = append(s.validOps, true)
 	task.IsVirtualStatus = true
 
 	log.InfraLogger.V(6).Infof(
@@ -347,6 +351,7 @@ func (s *Statement) Allocate(task *pod_info.PodInfo, hostname string) error {
 			},
 		},
 	)
+	s.validOps = append(s.validOps, true)
 	task.IsVirtualStatus = true
 
 	log.InfraLogger.V(6).Infof(
@@ -504,18 +509,22 @@ func (s *Statement) ConvertAllAllocatedToPipelined(jobID common_info.PodGroupID)
 	}
 
 	var newOperations []Operation
-	for _, op := range s.operations {
+	var newValidOps []bool
+	for i, op := range s.operations {
 		if !(op.TaskInfo().Job == jobID && op.Name() == allocate) {
 			newOperations = append(newOperations, op)
+			newValidOps = append(newValidOps, s.validOps[i])
 		}
 	}
 	s.operations = newOperations
+	s.validOps = newValidOps
 
 	return nil
 }
 
 func (s *Statement) clearOperations() {
-	s.operations = []Operation{}
+	s.operations = s.operations[:0]
+	s.validOps = s.validOps[:0]
 }
 
 func (s *Statement) Discard() {
@@ -638,6 +647,8 @@ func (s *Statement) undoOperation(index int) error {
 			reverseOperation: redoOperation,
 		},
 	)
+	s.validOps = append(s.validOps, true)
+	s.toggleValidOp(index)
 
 	return err
 }
@@ -650,13 +661,14 @@ func (s *Statement) cleanupFailedAllocation(task *pod_info.PodInfo, node *node_i
 }
 
 func (s *Statement) operationValid(i int) bool {
-	for undoIndex, operation := range s.operations {
-		if operation.Name() != undo {
-			continue
-		}
-		if operation.(undoOperation).operationIndex == i {
-			return !s.operationValid(undoIndex)
-		}
+	return s.validOps[i]
+}
+
+// toggleValidOp flips the validity of operation at index and propagates through
+// any undo chain: if op[index] is itself an undoOperation, its target is toggled too.
+func (s *Statement) toggleValidOp(index int) {
+	s.validOps[index] = !s.validOps[index]
+	if undoOp, ok := s.operations[index].(undoOperation); ok {
+		s.toggleValidOp(undoOp.operationIndex)
 	}
-	return true
 }