Bug 908836
Summary: | libvirt: wrong cpu topology - AMD Bulldozer 62XX familly | ||
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Product: | Red Hat Enterprise Linux 6 | Reporter: | Chris Pelland <cpelland> |
Component: | libvirt | Assignee: | Peter Krempa <pkrempa> |
Status: | CLOSED ERRATA | QA Contact: | Virtualization Bugs <virt-bugs> |
Severity: | urgent | Docs Contact: | |
Priority: | urgent | ||
Version: | 6.4 | CC: | acathrow, asegundo, bazulay, berrange, bsarathy, cpelland, dallan, danken, dougsland, dyasny, dyuan, honzhang, iheim, jwest, ltroan, mzhan, pkrempa, rwu |
Target Milestone: | rc | Keywords: | ZStream |
Target Release: | --- | ||
Hardware: | Unspecified | ||
OS: | Unspecified | ||
Whiteboard: | |||
Fixed In Version: | libvirt-0.10.2-18.el6_4.1 | Doc Type: | Bug Fix |
Doc Text: |
Cause:
The AMD Bulldozer CPU architecture consists of so-called "modules". These are represented both as separate cores and separate threads. Management applications need to choose between one of the approaches. Libvirt wasn't providing enough information to do this.
Consequence:
Management applications weren't able to represent the modules in a bulldozer core according to their needs.
Fix:
The capabilities XML output now contains more information about the processor topology so that the management apps can extract the information they need.
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Story Points: | --- |
Clone Of: | Environment: | ||
Last Closed: | 2013-03-21 14:05:20 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: | 888503 | ||
Bug Blocks: | 907587 |
Description
Chris Pelland
2013-02-07 16:18:07 UTC
Verify it as follows. The result is expected. Move its status to VERIFIED. Versions # rpm -q libvirt libvirt-0.10.2-18.el6_4.1.x86_64 # cat /proc/cpuinfo|grep "model name"|uniq model name : AMD Opteron(tm) Processor 6282 SE # numactl --hardware available: 8 nodes (0-7) node 0 cpus: 0 4 8 12 16 20 24 28 node 0 size: 16349 MB node 0 free: 15389 MB node 1 cpus: 32 36 40 44 48 52 56 60 node 1 size: 16384 MB node 1 free: 15976 MB node 2 cpus: 1 5 9 13 17 21 25 29 node 2 size: 16384 MB node 2 free: 15753 MB node 3 cpus: 33 37 41 45 49 53 57 61 node 3 size: 16384 MB node 3 free: 15543 MB node 4 cpus: 2 6 10 14 18 22 26 30 node 4 size: 16384 MB node 4 free: 15925 MB node 5 cpus: 34 38 42 46 50 54 58 62 node 5 size: 16384 MB node 5 free: 15919 MB node 6 cpus: 35 39 43 47 51 55 59 63 node 6 size: 16384 MB node 6 free: 15817 MB node 7 cpus: 3 7 11 15 19 23 27 31 node 7 size: 16367 MB node 7 free: 15583 MB node distances: node 0 1 2 3 4 5 6 7 0: 10 16 16 22 16 16 22 22 1: 16 10 16 22 22 22 16 22 2: 16 16 10 16 22 22 22 16 3: 22 22 16 10 22 16 22 16 4: 16 22 22 22 10 16 16 16 5: 16 22 22 16 16 10 22 22 6: 22 16 22 22 16 22 10 16 7: 22 22 16 16 16 22 16 10 # virsh nodeinfo CPU model: x86_64 CPU(s): 64 CPU frequency: 2593 MHz CPU socket(s): 1 Core(s) per socket: 64 Thread(s) per core: 1 NUMA cell(s): 1 Memory size: 132035680 KiB # virsh capabilities <capabilities> ...... <host> ...... <topology> <cells num='8'> <cell id='0'> <cpus num='8'> <cpu id='0' socket_id='0' core_id='0' siblings='0,4'/> <cpu id='4' socket_id='0' core_id='1' siblings='0,4'/> <cpu id='8' socket_id='0' core_id='2' siblings='8,12'/> <cpu id='12' socket_id='0' core_id='3' siblings='8,12'/> <cpu id='16' socket_id='0' core_id='4' siblings='16,20'/> <cpu id='20' socket_id='0' core_id='5' siblings='16,20'/> <cpu id='24' socket_id='0' core_id='6' siblings='24,28'/> <cpu id='28' socket_id='0' core_id='7' siblings='24,28'/> </cpus> </cell> <cell id='1'> <cpus num='8'> <cpu id='32' socket_id='0' core_id='0' siblings='32,36'/> <cpu id='36' socket_id='0' core_id='1' siblings='32,36'/> <cpu id='40' socket_id='0' core_id='2' siblings='40,44'/> <cpu id='44' socket_id='0' core_id='3' siblings='40,44'/> <cpu id='48' socket_id='0' core_id='4' siblings='48,52'/> <cpu id='52' socket_id='0' core_id='5' siblings='48,52'/> <cpu id='56' socket_id='0' core_id='6' siblings='56,60'/> <cpu id='60' socket_id='0' core_id='7' siblings='56,60'/> </cpus> </cell> <cell id='2'> <cpus num='8'> <cpu id='1' socket_id='1' core_id='0' siblings='1,5'/> <cpu id='5' socket_id='1' core_id='1' siblings='1,5'/> <cpu id='9' socket_id='1' core_id='2' siblings='9,13'/> <cpu id='13' socket_id='1' core_id='3' siblings='9,13'/> <cpu id='17' socket_id='1' core_id='4' siblings='17,21'/> <cpu id='21' socket_id='1' core_id='5' siblings='17,21'/> <cpu id='25' socket_id='1' core_id='6' siblings='25,29'/> <cpu id='29' socket_id='1' core_id='7' siblings='25,29'/> </cpus> </cell> <cell id='3'> <cpus num='8'> <cpu id='33' socket_id='1' core_id='0' siblings='33,37'/> <cpu id='37' socket_id='1' core_id='1' siblings='33,37'/> <cpu id='41' socket_id='1' core_id='2' siblings='41,45'/> <cpu id='45' socket_id='1' core_id='3' siblings='41,45'/> <cpu id='49' socket_id='1' core_id='4' siblings='49,53'/> <cpu id='53' socket_id='1' core_id='5' siblings='49,53'/> <cpu id='57' socket_id='1' core_id='6' siblings='57,61'/> <cpu id='61' socket_id='1' core_id='7' siblings='57,61'/> </cpus> </cell> <cell id='4'> <cpus num='8'> <cpu id='2' socket_id='2' core_id='0' siblings='2,6'/> <cpu id='6' socket_id='2' core_id='1' siblings='2,6'/> <cpu id='10' socket_id='2' core_id='2' siblings='10,14'/> <cpu id='14' socket_id='2' core_id='3' siblings='10,14'/> <cpu id='18' socket_id='2' core_id='4' siblings='18,22'/> <cpu id='22' socket_id='2' core_id='5' siblings='18,22'/> <cpu id='26' socket_id='2' core_id='6' siblings='26,30'/> <cpu id='30' socket_id='2' core_id='7' siblings='26,30'/> </cpus> </cell> <cell id='5'> <cpus num='8'> <cpu id='34' socket_id='2' core_id='0' siblings='34,38'/> <cpu id='38' socket_id='2' core_id='1' siblings='34,38'/> <cpu id='42' socket_id='2' core_id='2' siblings='42,46'/> <cpu id='46' socket_id='2' core_id='3' siblings='42,46'/> <cpu id='50' socket_id='2' core_id='4' siblings='50,54'/> <cpu id='54' socket_id='2' core_id='5' siblings='50,54'/> <cpu id='58' socket_id='2' core_id='6' siblings='58,62'/> <cpu id='62' socket_id='2' core_id='7' siblings='58,62'/> </cpus> </cell> <cell id='6'> <cpus num='8'> <cpu id='35' socket_id='3' core_id='0' siblings='35,39'/> <cpu id='39' socket_id='3' core_id='1' siblings='35,39'/> <cpu id='43' socket_id='3' core_id='2' siblings='43,47'/> <cpu id='47' socket_id='3' core_id='3' siblings='43,47'/> <cpu id='51' socket_id='3' core_id='4' siblings='51,55'/> <cpu id='55' socket_id='3' core_id='5' siblings='51,55'/> <cpu id='59' socket_id='3' core_id='6' siblings='59,63'/> <cpu id='63' socket_id='3' core_id='7' siblings='59,63'/> </cpus> </cell> <cell id='7'> <cpus num='8'> <cpu id='3' socket_id='3' core_id='0' siblings='3,7'/> <cpu id='7' socket_id='3' core_id='1' siblings='3,7'/> <cpu id='11' socket_id='3' core_id='2' siblings='11,15'/> <cpu id='15' socket_id='3' core_id='3' siblings='11,15'/> <cpu id='19' socket_id='3' core_id='4' siblings='19,23'/> <cpu id='23' socket_id='3' core_id='5' siblings='19,23'/> <cpu id='27' socket_id='3' core_id='6' siblings='27,31'/> <cpu id='31' socket_id='3' core_id='7' siblings='27,31'/> </cpus> </cell> </cells> </topology> ...... </host> ...... </capabilities> # ./numatest.py Sockets: 4 Cores: 32 Threads: 64 # cat numatest.py #!/usr/bin/python # Amador Pahim <apahim> # Jan 12 2013 import libvirt from xml.dom import minidom c = libvirt.open("qemu:///system") caps = minidom.parseString(c.getCapabilities()) #caps = minidom.parse("capabilities.xml") host = caps.getElementsByTagName('host')[0] cells = host.getElementsByTagName('cells')[0] total_cpus = cells.getElementsByTagName('cpu').length socketIds = [] siblingsIds = [] socketIds = [ proc.getAttribute('socket_id') for proc in cells.getElementsByTagName('cpu') if proc.getAttribute('socket_id') not in socketIds ] siblingsIds = [ proc.getAttribute('siblings') for proc in cells.getElementsByTagName('cpu') if proc.getAttribute('siblings') not in siblingsIds ] print "Sockets:",len(set(socketIds)) print "Cores:",len(set(siblingsIds)) print "Threads:",total_cpus 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. http://rhn.redhat.com/errata/RHBA-2013-0664.html Peter, do we have tests for this BZ in make check? No, there are no automated tests for that code. Unfortunately the code partly depends on data provided by libnuma and we currently don't have a way how to trick it into reading test datasets. |