Mount new /dev/shm volume with max size

Signed-off-by: Alexey Rivkin <[email protected]>

Author: Alexey-Rivkin

.ci/jenkins/lib/build-matrix.yaml

@@ -32,9 +32,10 @@ kubernetes:
   namespace: swx-media
   limits: "{memory: 8Gi, cpu: 8000m}"
   requests: "{memory: 8Gi, cpu: 8000m}"
-  yaml: |
-    spec:
-      hostIPC: true
+
+# Mount large /dev/shm for UCX shared memory allocation
+empty_volumes:
+  - {mountPath: /dev/shm, memory: true}
 
 runs_on_dockers:
   - { name: "ubuntu24.04-pytorch", url: "nvcr.io/nvidia/pytorch:25.02-py3" }
@@ -66,6 +67,8 @@ steps:
     parallel: false
     timeout: "${TEST_TIMEOUT}"
     run: |
+      echo "DEBUG: /dev/shm size"
+      df -h /dev/shm
       .gitlab/test_cpp.sh ${NIXL_INSTALL_DIR}
 
   - name: Test Python