Some improvements in Nova Scheduler config

Registered by Dmitry Ukov on 2014-03-07

These improvements will help to reach more smooth VM distribution across non-homogeneous compute nodes.
Core and Disk filters are enabled as well.
---nova.conf---
scheduler_default_filters=RetryFilter,AvailabilityZoneFilter,RamFilter,CoreFilter,DiskFilter,ComputeFilter,ComputeCapabilitiesFilter,ImagePropertiesFilter
cpu_allocation_ratio=1.0
disk_allocation_ratio=1.0
ram_allocation_ratio=1.0
ram_weight_multiplier=0.0
scheduler_host_subset_size=30
---

Blueprint information

Status:
Complete
Approver:
Vladimir Kuklin
Priority:
Low
Drafter:
Dmitry Ukov
Direction:
Approved
Assignee:
Sergii Golovatiuk
Definition:
Approved
Series goal:
Accepted for 5.0.x
Implementation:
Implemented
Milestone target:
milestone icon 5.0
Started by
Mike Scherbakov on 2014-04-25
Completed by
Vladimir Kuklin on 2014-05-01

Related branches

Sprints

Whiteboard

Just for note: Nova compute RAM/CPU overcommitment options: cpu_allocation_ratio (default 16) , ram_allocation_ratio (default 1.5), disk_allocation_ratio (default 1.0).

Core and Disk filters should be enabled (they are disabled by default) in order to avoid compute node oveloading
- cpu_allocation_ratio=1.0 - Default 16.0 is way to big over commit ratio (potentially 16 vms on 1 core). 2.0 or 3.0 will be reasonable here.
- disk_allocation_ratio=1.0 - it is unsafe to over commit disk
- ram_allocation_ratio=1.0 - Actually we can use default value here.
- ram_weight_multiplier=0.0 and scheduler_host_subset_size=30 will help us to get random VMs distribution if compute nodes significantly differ from each other in terms of total RAM amount

Gerrit topic: https://review.openstack.org/#q,topic:bug/1300027,n,z

Addressed by: https://review.openstack.org/90106
    Implements filters and schedules in nova.cfg

Addressed by: https://review.openstack.org/97998
    Implements filters and schedules in nova.cfg

(?)

Work Items

This blueprint contains Public information 
Everyone can see this information.

Subscribers

No subscribers.