Merge pull request #126750 from AMDEPYC/uncore_v1

Split L3 Cache Topology Awareness in CPU Manager
2025-11-04 04:08:16 +00:00 · 2024-11-06 11:13:29 +00:00
parent f451aec237 b86eb19d30
commit 50d0f920c0
9 changed files with 1265 additions and 350 deletions
--- a/pkg/kubelet/cm/cpumanager/cpu_assignment.go
+++ b/pkg/kubelet/cm/cpumanager/cpu_assignment.go
@@ -118,6 +118,17 @@ func (n *numaFirst) takeFullSecondLevel() {
 	n.acc.takeFullSockets()
 }

+// Sort the UncoreCaches within the NUMA nodes.
+func (a *cpuAccumulator) sortAvailableUncoreCaches() []int {
+	var result []int
+	for _, numa := range a.sortAvailableNUMANodes() {
+		uncore := a.details.UncoreInNUMANodes(numa).UnsortedList()
+		a.sort(uncore, a.details.CPUsInUncoreCaches)
+		result = append(result, uncore...)
+	}
+	return result
+}
+
 // If NUMA nodes are higher in the memory hierarchy than sockets, then just
 // sort the NUMA nodes directly, and return them.
 func (n *numaFirst) sortAvailableNUMANodes() []int {
@@ -318,6 +329,12 @@ func (a *cpuAccumulator) isSocketFree(socketID int) bool {
 	return a.details.CPUsInSockets(socketID).Size() == a.topo.CPUsPerSocket()
 }

+// Returns true if the supplied UnCoreCache is fully available,
+// "fully available" means that all the CPUs in it are free.
+func (a *cpuAccumulator) isUncoreCacheFree(uncoreID int) bool {
+	return a.details.CPUsInUncoreCaches(uncoreID).Size() == a.topo.CPUDetails.CPUsInUncoreCaches(uncoreID).Size()
+}
+
 // Returns true if the supplied core is fully available in `a.details`.
 // "fully available" means that all the CPUs in it are free.
 func (a *cpuAccumulator) isCoreFree(coreID int) bool {
@@ -346,6 +363,17 @@ func (a *cpuAccumulator) freeSockets() []int {
 	return free
 }

+// Returns free UncoreCache IDs as a slice sorted by sortAvailableUnCoreCache().
+func (a *cpuAccumulator) freeUncoreCache() []int {
+	free := []int{}
+	for _, uncore := range a.sortAvailableUncoreCaches() {
+		if a.isUncoreCacheFree(uncore) {
+			free = append(free, uncore)
+		}
+	}
+	return free
+}
+
 // Returns free core IDs as a slice sorted by sortAvailableCores().
 func (a *cpuAccumulator) freeCores() []int {
 	free := []int{}
@@ -519,6 +547,62 @@ func (a *cpuAccumulator) takeFullSockets() {
 	}
 }

+func (a *cpuAccumulator) takeFullUncore() {
+	for _, uncore := range a.freeUncoreCache() {
+		cpusInUncore := a.topo.CPUDetails.CPUsInUncoreCaches(uncore)
+		if !a.needsAtLeast(cpusInUncore.Size()) {
+			continue
+		}
+		klog.V(4).InfoS("takeFullUncore: claiming uncore", "uncore", uncore)
+		a.take(cpusInUncore)
+	}
+}
+
+func (a *cpuAccumulator) takePartialUncore(uncoreID int) {
+	numCoresNeeded := a.numCPUsNeeded / a.topo.CPUsPerCore()
+
+	// determine the N number of free cores (physical cpus) within the UncoreCache, then
+	// determine the M number of free cpus (virtual cpus) that correspond with the free cores
+	freeCores := a.details.CoresNeededInUncoreCache(numCoresNeeded, uncoreID)
+	freeCPUs := a.details.CPUsInCores(freeCores.UnsortedList()...)
+
+	// claim the cpus if the free cpus within the UncoreCache can satisfy the needed cpus
+	claimed := (a.numCPUsNeeded == freeCPUs.Size())
+	klog.V(4).InfoS("takePartialUncore: trying to claim partial uncore",
+		"uncore", uncoreID,
+		"claimed", claimed,
+		"needed", a.numCPUsNeeded,
+		"cores", freeCores.String(),
+		"cpus", freeCPUs.String())
+	if !claimed {
+		return
+
+	}
+	a.take(freeCPUs)
+}
+
+// First try to take full UncoreCache, if available and need is at least the size of the UncoreCache group.
+// Second try to take the partial UncoreCache if available and the request size can fit w/in the UncoreCache.
+func (a *cpuAccumulator) takeUncoreCache() {
+	numCPUsInUncore := a.topo.CPUsPerUncore()
+	for _, uncore := range a.sortAvailableUncoreCaches() {
+		// take full UncoreCache if the CPUs needed is greater than free UncoreCache size
+		if a.needsAtLeast(numCPUsInUncore) {
+			a.takeFullUncore()
+		}
+
+		if a.isSatisfied() {
+			return
+		}
+
+		// take partial UncoreCache if the CPUs needed is less than free UncoreCache size
+		a.takePartialUncore(uncore)
+		if a.isSatisfied() {
+			return
+		}
+	}
+}
+
 func (a *cpuAccumulator) takeFullCores() {
 	for _, core := range a.freeCores() {
 		cpusInCore := a.topo.CPUDetails.CPUsInCores(core)
@@ -637,6 +721,14 @@ func (a *cpuAccumulator) iterateCombinations(n []int, k int, f func([]int) LoopC
 // or the remaining number of CPUs to take after having taken full sockets and NUMA nodes is less
 // than a whole NUMA node, the function tries to take whole physical cores (cores).
 //
+// If `PreferAlignByUncoreCache` is enabled, the function will try to optimally assign Uncorecaches.
+// If `numCPUs` is larger than or equal to the total number of CPUs in a Uncorecache, and there are
+// free (i.e. all CPUs within the Uncorecache are free) Uncorecaches, the function takes as many entire
+// cores from free Uncorecaches as possible. If/Once `numCPUs` is smaller than the total number of
+// CPUs in a free Uncorecache, the function scans each Uncorecache index in numerical order to assign
+// cores that will fit within the Uncorecache. If `numCPUs` cannot fit within any Uncorecache, the
+// function tries to take whole physical cores.
+//
 // If `numCPUs` is bigger than the total number of CPUs in a core, and there are
 // free (i.e. all CPUs in them are free) cores, the function takes as many entire free cores as possible.
 // The cores are taken from one socket at a time, and the sockets are considered by
@@ -658,7 +750,7 @@ func (a *cpuAccumulator) iterateCombinations(n []int, k int, f func([]int) LoopC
 // the least amount of free CPUs to the one with the highest amount of free CPUs (i.e. in ascending
 // order of free CPUs). For any NUMA node, the cores are selected from the ones in the socket with
 // the least amount of free CPUs to the one with the highest amount of free CPUs.
-func takeByTopologyNUMAPacked(topo *topology.CPUTopology, availableCPUs cpuset.CPUSet, numCPUs int, cpuSortingStrategy CPUSortingStrategy) (cpuset.CPUSet, error) {
+func takeByTopologyNUMAPacked(topo *topology.CPUTopology, availableCPUs cpuset.CPUSet, numCPUs int, cpuSortingStrategy CPUSortingStrategy, preferAlignByUncoreCache bool) (cpuset.CPUSet, error) {
 	acc := newCPUAccumulator(topo, availableCPUs, numCPUs, cpuSortingStrategy)
 	if acc.isSatisfied() {
 		return acc.result, nil
@@ -681,7 +773,17 @@ func takeByTopologyNUMAPacked(topo *topology.CPUTopology, availableCPUs cpuset.C
 		return acc.result, nil
 	}

-	// 2. Acquire whole cores, if available and the container requires at least
+	// 2. If PreferAlignByUncoreCache is enabled, acquire whole UncoreCaches
+	//    if available and the container requires at least a UncoreCache's-worth
+	//    of CPUs. Otherwise, acquire CPUs from the least amount of UncoreCaches.
+	if preferAlignByUncoreCache {
+		acc.takeUncoreCache()
+		if acc.isSatisfied() {
+			return acc.result, nil
+		}
+	}
+
+	// 3. Acquire whole cores, if available and the container requires at least
 	//    a core's-worth of CPUs.
 	//    If `CPUSortingStrategySpread` is specified, skip taking the whole core.
 	if cpuSortingStrategy != CPUSortingStrategySpread {
@@ -691,7 +793,7 @@ func takeByTopologyNUMAPacked(topo *topology.CPUTopology, availableCPUs cpuset.C
 		}
 	}

-	// 3. Acquire single threads, preferring to fill partially-allocated cores
+	// 4. Acquire single threads, preferring to fill partially-allocated cores
 	//    on the same sockets as the whole cores we have already taken in this
 	//    allocation.
 	acc.takeRemainingCPUs()
@@ -769,8 +871,10 @@ func takeByTopologyNUMADistributed(topo *topology.CPUTopology, availableCPUs cpu
 	// If the number of CPUs requested cannot be handed out in chunks of
 	// 'cpuGroupSize', then we just call out the packing algorithm since we
 	// can't distribute CPUs in this chunk size.
+	// PreferAlignByUncoreCache feature not implemented here yet and set to false.
+	// Support for PreferAlignByUncoreCache to be done at beta release.
 	if (numCPUs % cpuGroupSize) != 0 {
-		return takeByTopologyNUMAPacked(topo, availableCPUs, numCPUs, cpuSortingStrategy)
+		return takeByTopologyNUMAPacked(topo, availableCPUs, numCPUs, cpuSortingStrategy, false)
 	}

 	// Otherwise build an accumulator to start allocating CPUs from.
@@ -953,7 +1057,7 @@ func takeByTopologyNUMADistributed(topo *topology.CPUTopology, availableCPUs cpu
 		// size 'cpuGroupSize' from 'bestCombo'.
 		distribution := (numCPUs / len(bestCombo) / cpuGroupSize) * cpuGroupSize
 		for _, numa := range bestCombo {
-			cpus, _ := takeByTopologyNUMAPacked(acc.topo, acc.details.CPUsInNUMANodes(numa), distribution, cpuSortingStrategy)
+			cpus, _ := takeByTopologyNUMAPacked(acc.topo, acc.details.CPUsInNUMANodes(numa), distribution, cpuSortingStrategy, false)
 			acc.take(cpus)
 		}

@@ -968,7 +1072,7 @@ func takeByTopologyNUMADistributed(topo *topology.CPUTopology, availableCPUs cpu
 				if acc.details.CPUsInNUMANodes(numa).Size() < cpuGroupSize {
 					continue
 				}
-				cpus, _ := takeByTopologyNUMAPacked(acc.topo, acc.details.CPUsInNUMANodes(numa), cpuGroupSize, cpuSortingStrategy)
+				cpus, _ := takeByTopologyNUMAPacked(acc.topo, acc.details.CPUsInNUMANodes(numa), cpuGroupSize, cpuSortingStrategy, false)
 				acc.take(cpus)
 				remainder -= cpuGroupSize
 			}
@@ -992,5 +1096,5 @@ func takeByTopologyNUMADistributed(topo *topology.CPUTopology, availableCPUs cpu

 	// If we never found a combination of NUMA nodes that we could properly
 	// distribute CPUs across, fall back to the packing algorithm.
-	return takeByTopologyNUMAPacked(topo, availableCPUs, numCPUs, cpuSortingStrategy)
+	return takeByTopologyNUMAPacked(topo, availableCPUs, numCPUs, cpuSortingStrategy, false)
 }
--- a/pkg/kubelet/cm/cpumanager/cpu_assignment_test.go
+++ b/pkg/kubelet/cm/cpumanager/cpu_assignment_test.go
@@ -668,6 +668,79 @@ func TestTakeByTopologyNUMAPacked(t *testing.T) {
 			"",
 			mustParseCPUSet(t, "0-29,40-69,30,31,70,71"),
 		},
+		// Test cases for PreferAlignByUncoreCache
+		{
+			"take cpus from two full UncoreCaches and partial from a single UncoreCache",
+			topoUncoreSingleSocketNoSMT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "1-15"),
+			10,
+			"",
+			cpuset.New(1, 2, 4, 5, 6, 7, 8, 9, 10, 11),
+		},
+		{
+			"take one cpu from dual socket with HT - core from Socket 0",
+			topoDualSocketHT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			cpuset.New(1, 2, 3, 4, 5, 7, 8, 9, 10, 11),
+			1,
+			"",
+			cpuset.New(2),
+		},
+		{
+			"take first available UncoreCache from first socket",
+			topoUncoreDualSocketNoSMT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "0-15"),
+			4,
+			"",
+			cpuset.New(0, 1, 2, 3),
+		},
+		{
+			"take all available UncoreCache from first socket",
+			topoUncoreDualSocketNoSMT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "2-15"),
+			6,
+			"",
+			cpuset.New(2, 3, 4, 5, 6, 7),
+		},
+		{
+			"take first available UncoreCache from second socket",
+			topoUncoreDualSocketNoSMT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "8-15"),
+			4,
+			"",
+			cpuset.New(8, 9, 10, 11),
+		},
+		{
+			"take first available UncoreCache from available NUMA",
+			topoUncoreSingleSocketMultiNuma,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "3,4-8,12"),
+			2,
+			"",
+			cpuset.New(4, 5),
+		},
+		{
+			"take cpus from best available UncoreCache group of multi uncore cache single socket - SMT enabled",
+			topoUncoreSingleSocketSMT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "2-3,10-11,4-7,12-15"),
+			6,
+			"",
+			cpuset.New(4, 5, 6, 12, 13, 14),
+		},
+		{
+			"take cpus from multiple UncoreCache of single socket - SMT enabled",
+			topoUncoreSingleSocketSMT,
+			StaticPolicyOptions{PreferAlignByUncoreCacheOption: true},
+			mustParseCPUSet(t, "1-7,9-15"),
+			10,
+			"",
+			mustParseCPUSet(t, "4-7,12-15,1,9"),
+		},
 	}...)

 	for _, tc := range testCases {
@@ -677,7 +750,7 @@ func TestTakeByTopologyNUMAPacked(t *testing.T) {
 				strategy = CPUSortingStrategySpread
 			}

-			result, err := takeByTopologyNUMAPacked(tc.topo, tc.availableCPUs, tc.numCPUs, strategy)
+			result, err := takeByTopologyNUMAPacked(tc.topo, tc.availableCPUs, tc.numCPUs, strategy, tc.opts.PreferAlignByUncoreCacheOption)
 			if tc.expErr != "" && err != nil && err.Error() != tc.expErr {
 				t.Errorf("expected error to be [%v] but it was [%v]", tc.expErr, err)
 			}
@@ -778,7 +851,7 @@ func TestTakeByTopologyWithSpreadPhysicalCPUsPreferredOption(t *testing.T) {
 		if tc.opts.DistributeCPUsAcrossCores {
 			strategy = CPUSortingStrategySpread
 		}
-		result, err := takeByTopologyNUMAPacked(tc.topo, tc.availableCPUs, tc.numCPUs, strategy)
+		result, err := takeByTopologyNUMAPacked(tc.topo, tc.availableCPUs, tc.numCPUs, strategy, tc.opts.PreferAlignByUncoreCacheOption)
 		if tc.expErr != "" && err.Error() != tc.expErr {
 			t.Errorf("testCase %q failed, expected error to be [%v] but it was [%v]", tc.description, tc.expErr, err)
 		}
--- a/pkg/kubelet/cm/cpumanager/cpu_manager_test.go
+++ b/pkg/kubelet/cm/cpumanager/cpu_manager_test.go
@@ -670,18 +670,22 @@ func TestCPUManagerGenerate(t *testing.T) {
 					{
 						Id:           0,
 						Threads:      []int{0},
+						UncoreCaches: []cadvisorapi.Cache{{Id: 1}},
 					},
 					{
 						Id:           1,
 						Threads:      []int{1},
+						UncoreCaches: []cadvisorapi.Cache{{Id: 1}},
 					},
 					{
 						Id:           2,
 						Threads:      []int{2},
+						UncoreCaches: []cadvisorapi.Cache{{Id: 1}},
 					},
 					{
 						Id:           3,
 						Threads:      []int{3},
+						UncoreCaches: []cadvisorapi.Cache{{Id: 1}},
 					},
 				},
 			},
--- a/pkg/kubelet/cm/cpumanager/policy_options.go
+++ b/pkg/kubelet/cm/cpumanager/policy_options.go
@@ -34,6 +34,7 @@ const (
 	AlignBySocketOption             string = "align-by-socket"
 	DistributeCPUsAcrossCoresOption string = "distribute-cpus-across-cores"
 	StrictCPUReservationOption      string = "strict-cpu-reservation"
+	PreferAlignByUnCoreCacheOption  string = "prefer-align-cpus-by-uncorecache"
 )

 var (
@@ -42,6 +43,7 @@ var (
 		AlignBySocketOption,
 		DistributeCPUsAcrossCoresOption,
 		StrictCPUReservationOption,
+		PreferAlignByUnCoreCacheOption,
 	)
 	betaOptions = sets.New[string](
 		FullPCPUsOnlyOption,
@@ -90,6 +92,9 @@ type StaticPolicyOptions struct {
 	DistributeCPUsAcrossCores bool
 	// Flag to remove reserved cores from the list of available cores
 	StrictCPUReservation bool
+	// Flag that makes best-effort to align CPUs to a uncorecache boundary
+	// As long as there are CPUs available, pods will be admitted if the condition is not met.
+	PreferAlignByUncoreCacheOption bool
 }

 // NewStaticPolicyOptions creates a StaticPolicyOptions struct from the user configuration.
@@ -131,6 +136,12 @@ func NewStaticPolicyOptions(policyOptions map[string]string) (StaticPolicyOption
 				return opts, fmt.Errorf("bad value for option %q: %w", name, err)
 			}
 			opts.StrictCPUReservation = optValue
+		case PreferAlignByUnCoreCacheOption:
+			optValue, err := strconv.ParseBool(value)
+			if err != nil {
+				return opts, fmt.Errorf("bad value for option %q: %w", name, err)
+			}
+			opts.PreferAlignByUncoreCacheOption = optValue
 		default:
 			// this should never be reached, we already detect unknown options,
 			// but we keep it as further safety.
@@ -147,6 +158,14 @@ func NewStaticPolicyOptions(policyOptions map[string]string) (StaticPolicyOption
 		return opts, fmt.Errorf("static policy options %s and %s can not be used at the same time", DistributeCPUsAcrossNUMAOption, DistributeCPUsAcrossCoresOption)
 	}

+	if opts.PreferAlignByUncoreCacheOption && opts.DistributeCPUsAcrossCores {
+		return opts, fmt.Errorf("static policy options %s and %s can not be used at the same time", PreferAlignByUnCoreCacheOption, DistributeCPUsAcrossCoresOption)
+	}
+
+	if opts.PreferAlignByUncoreCacheOption && opts.DistributeCPUsAcrossNUMA {
+		return opts, fmt.Errorf("static policy options %s and %s can not be used at the same time", PreferAlignByUnCoreCacheOption, DistributeCPUsAcrossNUMAOption)
+	}
+
 	return opts, nil
 }

--- a/pkg/kubelet/cm/cpumanager/policy_static.go
+++ b/pkg/kubelet/cm/cpumanager/policy_static.go
@@ -525,7 +525,8 @@ func (p *staticPolicy) takeByTopology(availableCPUs cpuset.CPUSet, numCPUs int)
 		}
 		return takeByTopologyNUMADistributed(p.topology, availableCPUs, numCPUs, cpuGroupSize, cpuSortingStrategy)
 	}
-	return takeByTopologyNUMAPacked(p.topology, availableCPUs, numCPUs, cpuSortingStrategy)
+
+	return takeByTopologyNUMAPacked(p.topology, availableCPUs, numCPUs, cpuSortingStrategy, p.options.PreferAlignByUncoreCacheOption)
 }

 func (p *staticPolicy) GetTopologyHints(s state.State, pod *v1.Pod, container *v1.Container) map[string][]topologymanager.TopologyHint {
--- a/pkg/kubelet/cm/cpumanager/policy_test.go
+++ b/pkg/kubelet/cm/cpumanager/policy_test.go
@@ -41,6 +41,7 @@ var (
 		NumCPUs:        12,
 		NumSockets:     2,
 		NumCores:       6,
+		NumUncoreCache: 1,
 		CPUDetails: map[int]topology.CPUInfo{
 			0:  {CoreID: 0, SocketID: 0, NUMANodeID: 0},
 			1:  {CoreID: 1, SocketID: 1, NUMANodeID: 1},
@@ -57,6 +58,106 @@ var (
 		},
 	}

+	topoUncoreDualSocketNoSMT = &topology.CPUTopology{
+		NumCPUs:        16,
+		NumSockets:     2,
+		NumCores:       16,
+		NumUncoreCache: 4,
+		CPUDetails: map[int]topology.CPUInfo{
+			0:  {CoreID: 0, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			1:  {CoreID: 1, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			2:  {CoreID: 2, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			3:  {CoreID: 3, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			4:  {CoreID: 4, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			5:  {CoreID: 5, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			6:  {CoreID: 6, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			7:  {CoreID: 7, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			8:  {CoreID: 8, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 2},
+			9:  {CoreID: 9, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 2},
+			10: {CoreID: 10, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 2},
+			11: {CoreID: 11, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 2},
+			12: {CoreID: 12, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 3},
+			13: {CoreID: 13, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 3},
+			14: {CoreID: 14, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 3},
+			15: {CoreID: 15, SocketID: 1, NUMANodeID: 0, UncoreCacheID: 3},
+		},
+	}
+
+	topoUncoreSingleSocketMultiNuma = &topology.CPUTopology{
+		NumCPUs:        16,
+		NumSockets:     1,
+		NumCores:       16,
+		NumUncoreCache: 4,
+		CPUDetails: map[int]topology.CPUInfo{
+			0:  {CoreID: 0, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			1:  {CoreID: 1, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			2:  {CoreID: 2, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			3:  {CoreID: 3, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			4:  {CoreID: 4, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			5:  {CoreID: 5, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			6:  {CoreID: 6, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			7:  {CoreID: 7, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			8:  {CoreID: 8, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 2},
+			9:  {CoreID: 9, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 2},
+			10: {CoreID: 10, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 2},
+			11: {CoreID: 11, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 2},
+			12: {CoreID: 12, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 3},
+			13: {CoreID: 13, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 3},
+			14: {CoreID: 14, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 3},
+			15: {CoreID: 15, SocketID: 0, NUMANodeID: 1, UncoreCacheID: 3},
+		},
+	}
+
+	topoUncoreSingleSocketSMT = &topology.CPUTopology{
+		NumCPUs:        16,
+		NumSockets:     1,
+		NumCores:       8,
+		NumUncoreCache: 2,
+		CPUDetails: map[int]topology.CPUInfo{
+			0:  {CoreID: 0, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			1:  {CoreID: 1, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			2:  {CoreID: 2, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			3:  {CoreID: 3, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			4:  {CoreID: 4, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			5:  {CoreID: 5, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			6:  {CoreID: 6, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			7:  {CoreID: 7, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			8:  {CoreID: 0, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			9:  {CoreID: 1, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			10: {CoreID: 2, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			11: {CoreID: 3, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			12: {CoreID: 4, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			13: {CoreID: 5, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			14: {CoreID: 6, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			15: {CoreID: 7, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+		},
+	}
+
+	topoUncoreSingleSocketNoSMT = &topology.CPUTopology{
+		NumCPUs:        16,
+		NumSockets:     1,
+		NumCores:       16,
+		NumUncoreCache: 4,
+		CPUDetails: map[int]topology.CPUInfo{
+			0:  {CoreID: 0, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			1:  {CoreID: 1, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			2:  {CoreID: 2, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			3:  {CoreID: 3, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 0},
+			4:  {CoreID: 4, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			5:  {CoreID: 5, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			6:  {CoreID: 6, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			7:  {CoreID: 7, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 1},
+			8:  {CoreID: 8, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 2},
+			9:  {CoreID: 9, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 2},
+			10: {CoreID: 10, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 2},
+			11: {CoreID: 11, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 2},
+			12: {CoreID: 12, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 3},
+			13: {CoreID: 13, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 3},
+			14: {CoreID: 14, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 3},
+			15: {CoreID: 15, SocketID: 0, NUMANodeID: 0, UncoreCacheID: 3},
+		},
+	}
+
 	topoDualSocketNoHT = &topology.CPUTopology{
 		NumCPUs:    8,
 		NumSockets: 2,
--- a/pkg/kubelet/cm/cpumanager/topology/topology.go
+++ b/pkg/kubelet/cm/cpumanager/topology/topology.go
@@ -36,9 +36,11 @@ type CPUDetails map[int]CPUInfo
 // Core - physical CPU, cadvisor - Core
 // Socket - socket, cadvisor - Socket
 // NUMA Node - NUMA cell, cadvisor - Node
+// UncoreCache - Split L3 Cache Topology, cadvisor
 type CPUTopology struct {
 	NumCPUs        int
 	NumCores       int
+	NumUncoreCache int
 	NumSockets     int
 	NumNUMANodes   int
 	CPUDetails     CPUDetails
@@ -62,6 +64,15 @@ func (topo *CPUTopology) CPUsPerSocket() int {
 	return topo.NumCPUs / topo.NumSockets
 }

+// CPUsPerUncore returns the number of logicial CPUs that are associated with
+// each UncoreCache
+func (topo *CPUTopology) CPUsPerUncore() int {
+	if topo.NumUncoreCache == 0 {
+		return 0
+	}
+	return topo.NumCPUs / topo.NumUncoreCache
+}
+
 // CPUCoreID returns the physical core ID which the given logical CPU
 // belongs to.
 func (topo *CPUTopology) CPUCoreID(cpu int) (int, error) {
@@ -90,11 +101,12 @@ func (topo *CPUTopology) CPUNUMANodeID(cpu int) (int, error) {
 	return info.NUMANodeID, nil
 }

-// CPUInfo contains the NUMA, socket, and core IDs associated with a CPU.
+// CPUInfo contains the NUMA, socket, UncoreCache and core IDs associated with a CPU.
 type CPUInfo struct {
 	NUMANodeID    int
 	SocketID      int
 	CoreID        int
+	UncoreCacheID int
 }

 // KeepOnly returns a new CPUDetails object with only the supplied cpus.
@@ -108,6 +120,67 @@ func (d CPUDetails) KeepOnly(cpus cpuset.CPUSet) CPUDetails {
 	return result
 }

+// UncoreCaches returns all the uncorecache Id (L3 Index) associated with the CPUs in this CPUDetails
+func (d CPUDetails) UncoreCaches() cpuset.CPUSet {
+	var numUnCoreIDs []int
+	for _, info := range d {
+		numUnCoreIDs = append(numUnCoreIDs, info.UncoreCacheID)
+	}
+	return cpuset.New(numUnCoreIDs...)
+}
+
+// UnCoresInNUMANodes returns all of the uncore IDs associated with the given
+// NUMANode IDs in this CPUDetails.
+func (d CPUDetails) UncoreInNUMANodes(ids ...int) cpuset.CPUSet {
+	var unCoreIDs []int
+	for _, id := range ids {
+		for _, info := range d {
+			if info.NUMANodeID == id {
+				unCoreIDs = append(unCoreIDs, info.UncoreCacheID)
+			}
+		}
+	}
+	return cpuset.New(unCoreIDs...)
+}
+
+// CoresNeededInUncoreCache returns either the full list of all available unique core IDs associated with the given
+// UnCoreCache IDs in this CPUDetails or subset that matches the ask.
+func (d CPUDetails) CoresNeededInUncoreCache(numCoresNeeded int, ids ...int) cpuset.CPUSet {
+	coreIDs := d.coresInUncoreCache(ids...)
+	if coreIDs.Size() <= numCoresNeeded {
+		return coreIDs
+	}
+	tmpCoreIDs := coreIDs.List()
+	return cpuset.New(tmpCoreIDs[:numCoresNeeded]...)
+}
+
+// Helper function that just gets the cores
+func (d CPUDetails) coresInUncoreCache(ids ...int) cpuset.CPUSet {
+	var coreIDs []int
+	for _, id := range ids {
+		for _, info := range d {
+			if info.UncoreCacheID == id {
+				coreIDs = append(coreIDs, info.CoreID)
+			}
+		}
+	}
+	return cpuset.New(coreIDs...)
+}
+
+// CPUsInUncoreCaches returns all the logical CPU IDs associated with the given
+// UnCoreCache IDs in this CPUDetails
+func (d CPUDetails) CPUsInUncoreCaches(ids ...int) cpuset.CPUSet {
+	var cpuIDs []int
+	for _, id := range ids {
+		for cpu, info := range d {
+			if info.UncoreCacheID == id {
+				cpuIDs = append(cpuIDs, cpu)
+			}
+		}
+	}
+	return cpuset.New(cpuIDs...)
+}
+
 // NUMANodes returns all of the NUMANode IDs associated with the CPUs in this
 // CPUDetails.
 func (d CPUDetails) NUMANodes() cpuset.CPUSet {
@@ -245,6 +318,16 @@ func (d CPUDetails) CPUsInCores(ids ...int) cpuset.CPUSet {
 	return cpuset.New(cpuIDs...)
 }

+func getUncoreCacheID(core cadvisorapi.Core) int {
+	if len(core.UncoreCaches) < 1 {
+		// In case cAdvisor is nil, failback to socket alignment since uncorecache is not shared
+		return core.SocketID
+	}
+	// Even though cadvisor API returns a slice, we only expect either 0 or a 1 uncore caches,
+	// so everything past the first entry should be discarded or ignored
+	return core.UncoreCaches[0].Id
+}
+
 // Discover returns CPUTopology based on cadvisor node info
 func Discover(machineInfo *cadvisorapi.MachineInfo) (*CPUTopology, error) {
 	if machineInfo.NumCores == 0 {
@@ -263,6 +346,7 @@ func Discover(machineInfo *cadvisorapi.MachineInfo) (*CPUTopology, error) {
 						CoreID:        coreID,
 						SocketID:      core.SocketID,
 						NUMANodeID:    node.Id,
+						UncoreCacheID: getUncoreCacheID(core),
 					}
 				}
 			} else {
@@ -277,6 +361,7 @@ func Discover(machineInfo *cadvisorapi.MachineInfo) (*CPUTopology, error) {
 		NumSockets:     machineInfo.NumSockets,
 		NumCores:       numPhysicalCores,
 		NumNUMANodes:   CPUDetails.NUMANodes().Size(),
+		NumUncoreCache: CPUDetails.UncoreCaches().Size(),
 		CPUDetails:     CPUDetails,
 	}, nil
 }
--- a/pkg/kubelet/cm/cpumanager/topology/topology_test.go
+++ b/pkg/kubelet/cm/cpumanager/topology/topology_test.go
--- a/pkg/kubelet/cm/cpumanager/topology_hints_test.go
+++ b/pkg/kubelet/cm/cpumanager/topology_hints_test.go
@@ -49,16 +49,16 @@ func returnMachineInfo() cadvisorapi.MachineInfo {
 		Topology: []cadvisorapi.Node{
 			{Id: 0,
 				Cores: []cadvisorapi.Core{
-					{SocketID: 0, Id: 0, Threads: []int{0, 6}},
-					{SocketID: 0, Id: 1, Threads: []int{1, 7}},
-					{SocketID: 0, Id: 2, Threads: []int{2, 8}},
+					{SocketID: 0, Id: 0, Threads: []int{0, 6}, UncoreCaches: []cadvisorapi.Cache{{Id: 1}}},
+					{SocketID: 0, Id: 1, Threads: []int{1, 7}, UncoreCaches: []cadvisorapi.Cache{{Id: 1}}},
+					{SocketID: 0, Id: 2, Threads: []int{2, 8}, UncoreCaches: []cadvisorapi.Cache{{Id: 1}}},
 				},
 			},
 			{Id: 1,
 				Cores: []cadvisorapi.Core{
-					{SocketID: 1, Id: 0, Threads: []int{3, 9}},
-					{SocketID: 1, Id: 1, Threads: []int{4, 10}},
-					{SocketID: 1, Id: 2, Threads: []int{5, 11}},
+					{SocketID: 1, Id: 0, Threads: []int{3, 9}, UncoreCaches: []cadvisorapi.Cache{{Id: 1}}},
+					{SocketID: 1, Id: 1, Threads: []int{4, 10}, UncoreCaches: []cadvisorapi.Cache{{Id: 1}}},
+					{SocketID: 1, Id: 2, Threads: []int{5, 11}, UncoreCaches: []cadvisorapi.Cache{{Id: 1}}},
 				},
 			},
 		},