abae526d8c
This update stops using sudo to create the target collect directory in /scratch to avoid permission errors when trying to add content without sudo. Doing so has the added benefit of leaving the collect bundles and content with ownership that matches the username collect was run from rather than root. Notice bundle file permissions at all levels Main Bundle: -rw-r--r-- 1 ericmac users /scratch/ALL_SUBCLOUDS_20240726.162635.tar Untared Main Bundle: [ericmac@controller-0 ALL_SUBCLOUDS_20240726.162635 ]$ ls -lrt -rw-r--r-- 1 ericmac users subcloud2-wrcp-master_20240726.162635.tar -rw-r--r-- 1 ericmac users subcloud1-wrcp-master_20240726.162635.tar -rw-r--r-- 1 ericmac users collect.log drwxr-xr-x 2 ericmac users subcloud2-wrcp-master_20240726.162635 drwxr-xr-x 2 ericmac users subcloud1-wrcp-master_20240726.162635 Untared Subcloud Bundle: [ericmac@controller-0 subcloud1-wrcp-master_20240726.162635 ]$ ls -lrt -rw-r--r-- 1 ericmac users controller-0_20240726.162635.tgz -rw-r--r-- 1 ericmac users report_tool.tgz -rw-r--r-- 1 ericmac users report_analysis.tgz -rw-r--r-- 1 ericmac users collect.log This update also adds /var/log/lastlog to the varlog.exclude file. This 'lastlog' file is used to record the last login times for each user. It is a sparse data file that can grow very large when WAD is enabled. So large that collect is seen to fail due to out of space error. Test Plan: run each test case - with and without the --report option - using sysadmin username and user sccount created with ldapusersetup PASS: Verify bundle file permissions at all levels PASS: Verify /var/run/lastlog is excluded PASS: Verify collect local PASS: Verify collect remote PASS: Verify collect from multiple subclouds, some with system nodes Story: 2010533 Task: 50670 Change-Id: If7c01c2c9a32d37c72f6304a1d9381b9cc42e740 Signed-off-by: Eric MacDonald <eric.macdonald@windriver.com>
utilities
This file serves as documentation for the components and features included on the utilities repository.
PCI IRQ Affinity Agent
While in OpenStack it is possible to enable instances to use PCI devices, the interrupts generated by these devices may be handled by host CPUs that are unrelated to the instance, and this can lead to a performance that is lower than it could be if the device interrupts were handled by the instance CPUs.
The agent only acts over instances with dedicated vCPUs. For instances using shared vCPUs no action will be taken by the agent.
The expected outcome from the agent operation is achieving a higher performance by assigning the instances core to handle the interrupts from PCI devices used by these instances and avoid interrupts consuming excessive cycles from the platform cores.
Agent operation
The agent operates by listening to RabbitMQ notifications from Nova. When an instance is created or moved to the host, the agent checks for an specific flavor spec (detailed below) and if it does then it queries libvirt to map the instance vCPUs into pCPUs from the host.
Once the agent has the CPU mapping, it determines the IRQ for each PCI device used by the instance, and then it loops over all PCI devices and determines which host NUMA node is associated with the device, the pCPUs that are associated with the NUMA node and finally set the CPU affinity for the IRQs of the PCI device based on the pCPU list.
There is also a periodic audit that runs every minute and loops over the existing IRQs, so that if there are new IRQs that weren't mapped before the agent maps them, and if there are PCI devices that aren't associated to an instance that they were before, their IRQ affinity is reset to the default value.
Flavor spec
The PCI IRQ Affinity Agent uses a specific flavor spec for PCI interrupt affining, that is used to determine which vCPUs assigned to the instance must handle the interrupts from the PCI devices:
hw:pci_irq_affinity_mask=<vcpus_cpulist>
Where vcpus_cpulist can assume a comma-separated list of
values that can be expressed as:
int: the vCPU expressed byintwill be assigned to handle the interruptions from the PCI devicesint1-int2: the vCPUs betweenint1andint2(inclusive) will be used to handle the interruptions from the PCI devices^int: the vCPU expressed byintwill not be assigned to handle the interruptions from the PCI devices and shall be used to exclude a vCPU that was included in a previous range
NOTE: int must be a value between
0 and flavor.vcpus - 1
Example: hw_pci_irq_affinity_mask=1-4,^3,6 means that
vCPUs with indexes 1,2,4 and 6 from the vCPU list that Nova
allocates to the instance will be assigned to handle interruptions from
the PCI devices.
Limitations
- No CPU affining is performed for instances using shared CPUs (i.e.,
when using flavor spec
hw:cpu_policy=shared) - No CPU affining will be performed when invalid ranges are specified on the flavor spec, the agent instead will log error messages indicating the problem
Agent packaging
The agent code resides on the starlingx/utilities repo,
along with the spec and docker_image files that are used to build a
CentOS image with the agent wheel installed on it.
The agent is deployed by Armada along with the other OpenStack helm
charts; refer to PCI
IRQ Affinity Agent helm chart on
starlingx/openstack-armada-app repository.