Bug 658891
| Summary: | [6.0.z FEAT] Port KVM bug fixes for cr_access to RHEL 6 [rhel-6.0.z] | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 6 | Reporter: | RHEL Program Management <pm-rhel> |
| Component: | kernel | Assignee: | Karen Noel <knoel> |
| Status: | CLOSED ERRATA | QA Contact: | Red Hat Kernel QE team <kernel-qe> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 6.0 | CC: | aliguori, bcao, bsarathy, bugproxy, dhoward, dshaks, fhrbata, jjarvis, jmalanik, jwest, knoel, lihuang, michen, mwagner, nobody+PNT0273897, pm-eus, qcai, sbest, snagar, tburke, wquan |
| Target Milestone: | rc | Keywords: | FutureFeature, ZStream |
| Target Release: | --- | ||
| Hardware: | other | ||
| OS: | All | ||
| Whiteboard: | |||
| Fixed In Version: | kernel-2.6.32-71.17.1.el6 | Doc Type: | Enhancement |
| Doc Text: |
Prior to this update, running context-switch intensive workloads on KVM guests resulted in a large number of exits (kvm_exit) due to control register (CR) accesses by the guest, thus, resulting in poor performance. This update includes a number of optimizations which allow the guest not to exit to the hypervisor in the aforementioned case and improve the overall performance.
|
Story Points: | --- |
| Clone Of: | Environment: | ||
| Last Closed: | 2011-02-22 17:40:14 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
| Bug Depends On: | 645898 | ||
| Bug Blocks: | |||
|
Description
RHEL Program Management
2010-12-01 15:05:26 UTC
Compared the times kvm_exit entries due to cr_access between 2.6.32-71.15.1.el6.x86_64 and 2.6.32-71.17.1.el6.x86_64. Test on following steps: 1.on the host #mount -t debugfs none /sys/kernel/debug #echo 1 >/sys/kernel/debug/tracing/events/kvm/enable 2.start a linux guest (also tried start a windows guest with cpu load via vmprime.exe) 3.check how many times kvm_exit entries due to cr_access in 5 mins #cat /sys/kernel/debug/tracing/trace_pipe|grep kvm_exit|grep cr_access|wc -l following is the results : /------------------------------------------------------\ | | win08R2 | rhel6 | |--------------------------|--------------|------------| |2.6.32-71.15.1.el6.x86_64 | 5825 | 6780 | |--------------------------|--------------|------------| |2.6.32-71.17.1.el6.x86_64 | 400 | 145 | \------------------------------------------------------/ bcao---->avi Is this the right way to verify this issue ?Does this issue has been fixed base on above? Mike (In reply to comment #6) > Is this the right way to verify this issue ?Does this issue has been fixed base > on above? Yes. An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on therefore solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHSA-2011-0283.html
Technical note added. If any revisions are required, please edit the "Technical Notes" field
accordingly. All revisions will be proofread by the Engineering Content Services team.
New Contents:
Prior to this update, running context-switch intensive workloads on KVM guests resulted in a large number of exits (kvm_exit) due to control register (CR) accesses by the guest, thus, resulting in poor performance. This update includes a number of optimizations which allow the guest not to exit to the hypervisor in the aforementioned case and improve the overall performance.
*** Bug 683788 has been marked as a duplicate of this bug. *** |