As discussed in this Slack conversation, I am trying to run a misalignment test scenario to measure the impact of misaligned devices on workload performance. During testing, I discovered that the distinctAttribute constraint does not appear to behave as expected.
I am running RKE2 Kubernetes 1.34 with the following feature gates enabled:
--feature-gates=DRAConsumableCapacity=true,DRAResourceClaimDeviceStatus=true
My test workload configuration is as follows:
apiVersion: batch/v1
kind: Job
metadata:
name: gpu-cpu
spec:
template:
spec:
restartPolicy: Never
containers:
- image: ghcr.io/coreweave/nccl-tests:12.9.1-devel-ubuntu22.04-nccl2.28.3-1-8b67957
name: test
command:
- /bin/bash
- -c
- |
set -eux
sleep infinity
resources:
claims:
- name: gpu
resourceClaims:
- name: gpu
resourceClaimTemplateName: gpu-cpu
---
apiVersion: resource.k8s.io/v1
kind: ResourceClaimTemplate
metadata:
name: gpu-cpu
spec:
spec:
devices:
requests:
- name: nic
exactly:
deviceClassName: dra.net
count: 1
selectors:
- cel:
expression: device.attributes["dra.net"].rdma == true
- name: cpu
exactly:
deviceClassName: dra.cpu
capacity:
requests:
dra.cpu/cpu: "5"
constraints:
- distinctAttribute: "dra.net/numaNode"
requests: ["cpu", "nic"]
The ResourceClaim status shows the following allocation:
Name: gpu-cpu-qx5ms-gpu-694lq
Namespace: default
Labels: <none>
Annotations: resource.kubernetes.io/pod-claim-name: gpu
API Version: resource.k8s.io/v1
Kind: ResourceClaim
Metadata:
Creation Timestamp: 2026-02-16T11:14:11Z
Finalizers:
resource.kubernetes.io/delete-protection
Generate Name: gpu-cpu-qx5ms-gpu-
Owner References:
API Version: v1
Block Owner Deletion: true
Controller: true
Kind: Pod
Name: gpu-cpu-qx5ms
UID: 5a685ca8-56a4-473d-a6ea-7f804adb81d2
Resource Version: 32226
UID: de2970e8-ea8b-493d-8a92-109e82c7a44b
Spec:
Devices:
Constraints:
Distinct Attribute: dra.net/numaNode
Requests:
cpu
nic
Requests:
Exactly:
Allocation Mode: ExactCount
Count: 1
Device Class Name: dra.net
Selectors:
Cel:
Expression: device.attributes["dra.net"].rdma == true
Name: nic
Exactly:
Allocation Mode: ExactCount
Capacity:
Requests:
dra.cpu/cpu: 5
Count: 1
Device Class Name: dra.cpu
Name: cpu
Status:
Allocation:
Devices:
Results:
Device: pci-0000-3f-00-0
Driver: dra.net
Pool: x-03-21
Request: nic
Consumed Capacity:
dra.cpu/cpu: 5
Device: cpudevnuma000
Driver: dra.cpu
Pool: x-03-21
Request: cpu
Share ID: 1f4fd174-a7b9-4a52-a998-7e044a2e0990
Node Selector:
Node Selector Terms:
Match Fields:
Key: metadata.name
Operator: In
Values:
x-03-21
Reserved For:
Name: gpu-cpu-qx5ms
Resource: pods
UID: 5a685ca8-56a4-473d-a6ea-7f804adb81d2
Events: <none>
Despite specifying distinctAttribute: "dra.net/numaNode" in the ResourceClaimTemplate, the NIC (pci-0000-3f-00-0) and CPU (cpudevnuma000) were allocated on the same NUMA node in this case.
CPU resourceSlice:
Attributes:
dra.cpu/numCPUs:
Int: 144
dra.cpu/numaNodeID:
Int: 0
dra.cpu/smtEnabled:
Bool: true
dra.cpu/socketID:
Int: 0
dra.net/numaNode:
Int: 0
Capacity:
dra.cpu/cpu:
Value: 144
Name: cpudevnuma000
Allow Multiple Allocations: true
DRANET resourceSlice:
Attributes:
dra.net/alias:
String:
dra.net/ebpf:
Bool: false
dra.net/encapsulation:
String: ether
dra.net/ifName:
String: ens1006f0np0
dra.net/mtu:
Int: 9216
dra.net/numaNode:
Int: 0
dra.net/pciAddress:
String: 0000:3f:00.0
dra.net/pciDevice:
String: MT43244 BlueField-3 integrated ConnectX-7 network controller
dra.net/pciSubsystem:
String: 0021
dra.net/pciVendor:
String: Mellanox Technologies
dra.net/rdma:
Bool: true
dra.net/sriov:
Bool: true
dra.net/sriovVfs:
Int: 0
dra.net/state:
String: up
dra.net/type:
String: device
dra.net/virtual:
Bool: false
resource.kubernetes.io/pcieRoot:
String: pci0000:3a
Name: pci-0000-3f-00-0
However, at the host level, the container process appears to be running on a CPU from NUMA 1:
ps -Leo pid,tid,psr,comm | grep 2349207
2349207 2349207 84 sleep
Then numactl:
numactl -H
available: 2 nodes (0-1)
node 0 cpus: 0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215
node 0 size: 772578 MB
node 0 free: 333969 MB
node 1 cpus: 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287
node 1 size: 774077 MB
node 1 free: 523307 MB
node distances:
node 0 1
0: 10 21
1: 21 10
Am I understanding this correctly? Even though the CPU is allocated from NUMA 0 in the ResourceClaim, the container is allowed to run on any CPU by the scheduler, which can result in the process actually executing on a core from NUMA 1 ?
I also checked the cpuset inside the container:
tests# cat /sys/fs/cgroup/cpuset.cpus.effective
0-287
Does this mean that the container has access to all cpu cores over all numa nodes ?
As discussed in this Slack conversation, I am trying to run a misalignment test scenario to measure the impact of misaligned devices on workload performance. During testing, I discovered that the distinctAttribute constraint does not appear to behave as expected.
I am running RKE2 Kubernetes 1.34 with the following feature gates enabled:
--feature-gates=DRAConsumableCapacity=true,DRAResourceClaimDeviceStatus=trueMy test workload configuration is as follows:
The ResourceClaim status shows the following allocation:
Despite specifying distinctAttribute: "dra.net/numaNode" in the ResourceClaimTemplate, the NIC (pci-0000-3f-00-0) and CPU (cpudevnuma000) were allocated on the same NUMA node in this case.
CPU resourceSlice:
DRANET resourceSlice:
However, at the host level, the container process appears to be running on a CPU from NUMA 1:
Then numactl:
Am I understanding this correctly? Even though the CPU is allocated from NUMA 0 in the ResourceClaim, the container is allowed to run on any CPU by the scheduler, which can result in the process actually executing on a core from NUMA 1 ?
I also checked the cpuset inside the container:
Does this mean that the container has access to all cpu cores over all numa nodes ?