scheduler: feasibility check that memory_max fits in total

scheduler/feasible/rank.go

@@ -383,6 +383,13 @@ NEXTNODE:
 			if iter.memoryOversubscription {
 				taskResources.Memory.MemoryMaxMB = safemath.Add(
 					int64(task.Resources.MemoryMaxMB), int64(task.Resources.SecretsMB))
+
+				if taskResources.Memory.MemoryMaxMB > option.Node.NodeResources.Memory.MemoryMB {
+					iter.ctx.Metrics().FilterNode(option.Node,
+						"task memory_max exceeds maximum available memory")
+					netIdx.Release()
+					continue NEXTNODE
+				}
 			}
 
 			// Check if we need a network resource

scheduler/feasible/rank_test.go

@@ -110,6 +110,18 @@ func TestBinPackIterator_NoExistingAlloc(t *testing.T) {
 				},
 			},
 		},
+		{
+			Node: &structs.Node{
+				// Empty but memory_max won't fit
+				NodeResources: &structs.NodeResources{
+					Processors: processorResources4096,
+					Cpu:        legacyCpuResources4096,
+					Memory: structs.NodeMemoryResources{
+						MemoryMB: 1024,
+					},
+				},
+			},
+		},
 	}
 	static := NewStaticRankIterator(ctx, nodes)
 
@@ -119,8 +131,9 @@ func TestBinPackIterator_NoExistingAlloc(t *testing.T) {
 			{
 				Name: "web",
 				Resources: &structs.Resources{
-					CPU:      1024,
-					MemoryMB: 1024,
+					CPU:         1024,
+					MemoryMB:    1024,
+					MemoryMaxMB: 2048,
 				},
 			},
 		},
@@ -132,19 +145,18 @@ func TestBinPackIterator_NoExistingAlloc(t *testing.T) {
 	scoreNorm := NewScoreNormalizationIterator(ctx, binp)
 
 	out := collectRanked(scoreNorm)
-	if len(out) != 2 {
-		t.Fatalf("Bad: %v", out)
-	}
-	if out[0] != nodes[0] || out[1] != nodes[2] {
-		t.Fatalf("Bad: %v", out)
-	}
+	must.Len(t, 2, out, must.Sprint("expected 2 scored nodes"))
+
+	must.Eq(t, nodes[0], out[0], must.Sprint("expected nodes[0] first"))
+	must.Eq(t, nodes[2], out[1], must.Sprint("expected nodes[2] second"))
+	must.Eq(t, 1.0, out[0].FinalScore, must.Sprint("bad score"))
+	must.Greater(t, 0.50, out[1].FinalScore, must.Sprint("bad score"))
+	must.Less(t, 0.60, out[1].FinalScore, must.Sprint("bad score"))
+
+	// un-feasible nodes node[1] and node[3] are not scored
+	must.Eq(t, 2,
+		ctx.metrics.ConstraintFiltered["task memory_max exceeds maximum available memory"])
 
-	if out[0].FinalScore != 1.0 {
-		t.Fatalf("Bad Score: %v", out[0].FinalScore)
-	}
-	if out[1].FinalScore < 0.50 || out[1].FinalScore > 0.60 {
-		t.Fatalf("Bad Score: %v", out[1].FinalScore)
-	}
 }
 
 // TestBinPackIterator_NoExistingAlloc_MixedReserve asserts that node's with

website/content/docs/upgrade/upgrade-specific.mdx

@@ -18,7 +18,12 @@ used to document those details separately from the standard upgrade flow.
 
 In Nomad 1.11.0, submitting a sysbatch job with a `reschedule` block returns
 an error instead of being silently ignored, as it was in previous versions. The
-same behavior applies to system jobs. 
+same behavior applies to system jobs.
+
+#### Memory oversubscription checked against total memory on node
+
+In Nomad 1.11.0, the scheduler checks that that the `resources.memory_max` of a
+task doesn't exceed the total memory on a given node.
 
 ## Nomad 1.10.2