Bug 1547954 - [RFE][Deployment] add ability to configure extra CPU flags for named CPU models
Summary: [RFE][Deployment] add ability to configure extra CPU flags for named CPU models
Keywords:
Status: CLOSED ERRATA
Alias: None
Product: Red Hat OpenStack
Classification: Red Hat
Component: puppet-nova
Version: 14.0 (Rocky)
Hardware: All
OS: Linux
high
high
Target Milestone: Upstream M2
: 14.0 (Rocky)
Assignee: Rajesh Tailor
QA Contact: OSP DFG:Compute
URL:
Whiteboard:
Depends On: 1398343 1570610 1570611 1570614 1570617
Blocks: 1571741 1571744 1571750 1571756
TreeView+ depends on / blocked
 
Reported: 2018-02-22 11:20 UTC by Lee Yarwood
Modified: 2023-03-21 18:48 UTC (History)
21 users (show)

Fixed In Version: puppet-nova-13.1.1-0.20180709142740.fa5ce48.el7ost
Doc Type: Enhancement
Doc Text:
With this release, Nova's libvirt driver now allows the specification of granular CPU feature flags when configuring CPU models. One benefit of this change is the alleviation of a performance degradation experienced on guests running with certain Intel-based virtual CPU models after application of the "Meltdown" CVE fixes. This guest performance impact is reduced by exposing the CPU feature flag 'PCID' ("Process-Context ID") to the *guest* CPU, assuming that the PCID flag is available in the physical hardware itself. For more details, refer to the documentation of ``[libvirt]/cpu_model_extra_flags`` in ``nova.conf`` for usage details.
Clone Of: 1398343
: 1571741 1571744 1571750 1571756 (view as bug list)
Environment:
Last Closed: 2019-01-11 11:48:58 UTC
Target Upstream Version:
Embargoed:
ratailor: needinfo+

Attachments (Terms of Use)


Links
System ID Private Priority Status Summary Last Updated
OpenStack gerrit 561796 0 None None None 2018-04-17 06:59:45 UTC
Red Hat Issue Tracker OSP-23327 0 None None None 2023-03-21 18:48:07 UTC
Red Hat Product Errata RHEA-2019:0045 0 None None None 2019-01-11 11:49:22 UTC

Comment 6 Rajesh Tailor 2018-10-22 07:22:16 UTC 
This feature can be enabled by setting below parameter in an environment file.
You can pass list of cpu model flags.

parameter_defaults:
  ComputeExtraConfig:
    nova::compute::libvirt::libvirt_cpu_model_extra_flags: 'PCID, pdpe1gb'
Comment 11 errata-xmlrpc 2019-01-11 11:48:58 UTC 
Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

https://access.redhat.com/errata/RHEA-2019:0045
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