Feat/cpu topology profile split

README.md

@@ -66,6 +66,20 @@ Only used with `compute.cpu-mode` is set to `custom`.
 For more details please refer to the Nova [configuration reference](https://docs.openstack.org/nova/latest/admin/cpu-models.html)
 for cpu models.
 
+* `compute.cpu-pinning-profile` CPU topology profile for Nova pinning
+
+When unset (default), the snap uses EPA-returned `allocated_cores` and
+`shared_cpus` directly.
+
+When set to JSON (as sent by the charm) like:
+
+`{"dedicated_percentage": 40, "requested_cores_percentage": 90}`
+
+the snap requests EPA `allocated_cores` sized by `requested_cores_percentage`
+using the `allocate_cores_percent` socket action, then applies the
+`dedicated_percentage` split strategy to produce Nova's
+`cpu_dedicated_set`/`cpu_shared_set`.
+
 * `compute.spice-proxy-address` (`localhost`) IP address for SPICE consoles
 
 IP address to use for configuration of SPICE consoles in instances.

openstack_hypervisor/cli/common.py

@@ -12,6 +12,8 @@
 
 from .schemas import (
     ActionType,
+    AllocateCoresPercentRequest,
+    AllocateCoresPercentResponse,
     AllocateCoresRequest,
     AllocateCoresResponse,
     AllocateHugepagesRequest,
@@ -57,6 +59,7 @@ def socket_path(snap: Snap) -> str:
 def _communicate_with_socket(
     request: Union[
         AllocateCoresRequest,
+        AllocateCoresPercentRequest,
         AllocateNumaCoresRequest,
         AllocateHugepagesRequest,
         GetMemoryInfoRequest,
@@ -83,7 +86,7 @@ def _communicate_with_socket(
     try:
         with pysocket.socket(pysocket.AF_UNIX, pysocket.SOCK_STREAM) as s:
             s.connect(socket_path)
-            s.sendall(request.json().encode())
+            s.sendall(request.model_dump_json(by_alias=True, exclude_none=True).encode())
             data = s.recv(4096)
             response_dict = json.loads(data.decode())
             if "error" in response_dict:
@@ -129,3 +132,22 @@ def get_cpu_pinning_from_socket(
     except (SocketCommunicationError, EPAOrchestratorError) as e:
         logging.error("Failed to get CPU pinning info from socket: {}".format(e))
         raise
+
+
+def get_cpu_pinning_percent_from_socket(
+    service_name: str,
+    socket_path: str,
+    requested_cores_percentage: int,
+) -> str:
+    """Get allocated cores from EPA based on requested percentage.
+
+    Returns EPA `allocated_cores` only; callers can derive any shared/dedicated
+    Nova sets they need.
+    """
+    request = AllocateCoresPercentRequest(
+        service_name=service_name,
+        action=ActionType.ALLOCATE_CORES_PERCENT,
+        percent=requested_cores_percentage,
+    )
+    response = _communicate_with_socket(request, AllocateCoresPercentResponse, socket_path)
+    return response.allocated_cores

openstack_hypervisor/cli/schemas.py

@@ -14,6 +14,7 @@ class ActionType(str, Enum):
     """Enum for different action types."""
 
     ALLOCATE_CORES = "allocate_cores"
+    ALLOCATE_CORES_PERCENT = "allocate_cores_percent"
     LIST_ALLOCATIONS = "list_allocations"
     ALLOCATE_NUMA_CORES = "allocate_numa_cores"
     GET_MEMORY_INFO = "get_memory_info"
@@ -30,8 +31,18 @@ class AllocateCoresRequest(BaseModel):
         default=0,
         description=("Number of dedicated cores requested. 0 keeps default policy."),
     )
-    numa_node: Optional[int] = Field(
-        default=None, ge=0, description="NUMA node (must be omitted for allocate_cores)"
+
+
+class AllocateCoresPercentRequest(BaseModel):
+    """Request model for allocating a percentage of isolated cores."""
+
+    version: Literal["1.0"] = Field(default=API_VERSION)
+    action: Literal[ActionType.ALLOCATE_CORES_PERCENT]
+    service_name: str = Field(description="Name of the requesting service")
+    percent: int = Field(
+        ge=-1,
+        le=100,
+        description="Percentage of isolated cores to allocate (0-100). -1 or 0 to deallocate.",
     )
 
 
@@ -40,7 +51,10 @@ class ListAllocationsRequest(BaseModel):
 
     version: Literal["1.0"] = Field(default=API_VERSION)
     action: Literal[ActionType.LIST_ALLOCATIONS]
-    service_name: str = Field(description="Name of the requesting service")
+    service_name: Optional[str] = Field(
+        default=None,
+        description="Name of the requesting service (optional)",
+    )
 
 
 class AllocateNumaCoresRequest(BaseModel):
@@ -64,7 +78,10 @@ class GetMemoryInfoRequest(BaseModel):
 
     version: Literal["1.0"] = Field(default=API_VERSION)
     action: Literal[ActionType.GET_MEMORY_INFO]
-    service_name: str = Field(description="Name of the requesting service")
+    service_name: Optional[str] = Field(
+        default=None,
+        description="Name of the requesting service (optional)",
+    )
 
 
 class AllocateHugepagesRequest(BaseModel):
@@ -97,6 +114,7 @@ def validate_hugepages_requested(cls, v: int) -> int:
 EpaRequest = Annotated[
     Union[
         AllocateCoresRequest,
+        AllocateCoresPercentRequest,
         AllocateNumaCoresRequest,
         ListAllocationsRequest,
         GetMemoryInfoRequest,
@@ -121,6 +139,19 @@ class AllocateCoresResponse(BaseModel):
     )
 
 
+class AllocateCoresPercentResponse(BaseModel):
+    """Pydantic model for allocate cores percent response."""
+
+    version: Literal["1.0"] = Field(default=API_VERSION)
+    service_name: str = Field(description="Name of the service that was allocated cores")
+    cores_allocated_count: int = Field(description="Number of cores that were actually allocated")
+    allocated_cores: str = Field(description="Comma-separated list of allocated CPU ranges")
+    total_available_cpus: int = Field(description="Total number of CPUs available in the system")
+    remaining_available_cpus: int = Field(
+        description="Number of CPUs still available for allocation"
+    )
+
+
 class AllocateNumaCoresResponse(BaseModel):
     """Pydantic model for NUMA allocate cores response."""
 

openstack_hypervisor/hooks.py

@@ -11,6 +11,7 @@
 import ipaddress
 import json
 import logging
+import math
 import os
 import platform
 import re
@@ -54,6 +55,7 @@
     EPAOrchestratorError,
     SocketCommunicationError,
     get_cpu_pinning_from_socket,
+    get_cpu_pinning_percent_from_socket,
     socket_path,
 )
 from openstack_hypervisor.log import setup_logging
@@ -354,6 +356,7 @@ def _get_local_ip_by_default_route() -> str:
     "compute.key": UNSET,
     "compute.migration-address": UNSET,
     "compute.resume-on-boot": True,
+    "compute.cpu-pinning-profile": UNSET,
     "compute.flavors": UNSET,
     "compute.pci-device-specs": [],
     "compute.pci-excluded-devices": [],
@@ -493,6 +496,52 @@ def _context_compat(context: Dict[str, Any]) -> Dict[str, Any]:
     return clean_context
 
 
+def _expand_cpu_ranges(cpu_ranges: str) -> List[int]:
+    """Expand comma-separated CPU ranges into an ordered list of CPU ids."""
+    cpus: List[int] = []
+    for token in cpu_ranges.split(","):
+        token = token.strip()
+        if not token:
+            continue
+        if "-" in token:
+            start, end = token.split("-", 1)
+            cpus.extend(list(range(int(start), int(end) + 1)))
+        else:
+            cpus.append(int(token))
+    return cpus
+
+
+def _compress_cpu_ranges(cpu_list: List[int]) -> str:
+    """Compress an ordered CPU list into Nova-compatible range notation."""
+    if not cpu_list:
+        return ""
+
+    ranges: List[str] = []
+    start = prev = cpu_list[0]
+    for cpu in cpu_list[1:]:
+        if cpu == prev + 1:
+            prev = cpu
+            continue
+        ranges.append(f"{start}-{prev}" if start != prev else str(start))
+        start = prev = cpu
+    ranges.append(f"{start}-{prev}" if start != prev else str(start))
+    return ",".join(ranges)
+
+
+def _split_dedicated_cores_by_profile(
+    dedicated_cores: str, dedicated_percentage: int
+) -> tuple[str, str]:
+    """Split dedicated cores into (shared_set, dedicated_set) by percentage."""
+    cores = _expand_cpu_ranges(dedicated_cores)
+    if not cores:
+        return "", ""
+
+    dedicated_count = math.ceil(len(cores) * dedicated_percentage / 100)
+    profile_dedicated = cores[:dedicated_count]
+    profile_shared = cores[dedicated_count:]
+    return _compress_cpu_ranges(profile_shared), _compress_cpu_ranges(profile_dedicated)
+
+
 TEMPLATES = {
     Path("etc/nova/nova.conf"): {
         "template": "nova.conf.j2",
@@ -3021,17 +3070,6 @@ def configure(snap: Snap) -> None:
 
 
 def _get_configure_context(snap: Snap) -> dict:
-    try:
-        cpu_shared_set, allocated_cores = get_cpu_pinning_from_socket(
-            service_name=snap.name, socket_path=socket_path(snap), cores_requested=0
-        )
-    except (SocketCommunicationError, EPAOrchestratorError) as e:
-        if "No Isolated CPUs configured" in str(e):
-            logging.info("No Isolated CPUs configured, continuing without CPU pinning.")
-            cpu_shared_set, allocated_cores = "", ""
-        else:
-            logging.warning(f"Failed to get CPU pinning info from EPA orchestrator: {e}")
-            cpu_shared_set, allocated_cores = "", ""
     context = snap.config.get_options(
         "compute",
         "network",
@@ -3047,13 +3085,6 @@ def _get_configure_context(snap: Snap) -> dict:
         "sev",
         "internal",
     ).as_dict()
-    context["compute"]["allocated_cores"] = allocated_cores
-    context["compute"]["cpu_shared_set"] = cpu_shared_set
-
-    context["compute"]["multipath_enabled"] = (
-        context["compute"].get("multipath_forced", False) or _is_multipathd_available()
-    )
-
     context.update(
         {
             "snap_common": str(snap.paths.common),
@@ -3062,6 +3093,42 @@ def _get_configure_context(snap: Snap) -> dict:
         }
     )
     context = _context_compat(context)
+    context.setdefault("compute", {})
+    context.setdefault("network", {})
+    context.setdefault("identity", {})
+    context["compute"]["multipath_enabled"] = (
+        context["compute"].get("multipath_forced", False) or _is_multipathd_available()
+    )
+
+    cpu_pinning_profile = context["compute"].get("cpu_pinning_profile")
+    try:
+        if cpu_pinning_profile:
+            dedicated_percentage = int(cpu_pinning_profile["dedicated_percentage"])
+            requested_cores_percentage = int(cpu_pinning_profile["requested_cores_percentage"])
+            allocated_cores = get_cpu_pinning_percent_from_socket(
+                service_name=snap.name,
+                socket_path=socket_path(snap),
+                requested_cores_percentage=requested_cores_percentage,
+            )
+            cpu_shared_set, allocated_cores = _split_dedicated_cores_by_profile(
+                allocated_cores, dedicated_percentage
+            )
+        else:
+            cpu_shared_set, allocated_cores = get_cpu_pinning_from_socket(
+                service_name=snap.name,
+                socket_path=socket_path(snap),
+                cores_requested=0,
+            )
+    except (SocketCommunicationError, EPAOrchestratorError) as e:
+        if "No Isolated CPUs configured" in str(e):
+            logging.info("No Isolated CPUs configured, continuing without CPU pinning.")
+        else:
+            logging.warning(f"Failed to get CPU pinning info from EPA orchestrator: {e}")
+        cpu_shared_set, allocated_cores = "", ""
+
+    context["compute"]["allocated_cores"] = allocated_cores
+    context["compute"]["cpu_shared_set"] = cpu_shared_set
+
     logging.info(context)
 
     if not context.get("identity"):

templates/nova.conf.j2

@@ -74,11 +74,15 @@ swtpm_group = snap_daemon
 # are placed on the shared set, but this can be customized in Nova. For more details on
 # emulator thread pinning policies and their impact, see:
 # https://docs.openstack.org/nova/latest/admin/cpu-topologies.html#customizing-instance-emulator-thread-pinning-policy
-{% if compute.allocated_cores and compute.cpu_shared_set -%}
+{% if compute.allocated_cores or compute.cpu_shared_set -%}
 [compute]
+{% if compute.allocated_cores -%}
 cpu_dedicated_set = {{ compute.allocated_cores }}
+{% endif -%}
+{% if compute.cpu_shared_set -%}
 cpu_shared_set = {{ compute.cpu_shared_set }}
 {% endif %}
+{% endif -%}
 
 {% if compute.rbd_secret_uuid -%}
 rbd_user = {{ compute.rbd_user }}