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(Fedora Virtualization List)
 
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[[Category:Virtualization]] <!-- do not copy into FWN issue -->
 
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{{Anchor|Virtualization}}
  
{{Anchor|Virtualization}}
 
  
 
== Virtualization ==
 
== Virtualization ==
 
In this section, we cover discussion of Fedora virtualization technologies on the
 
In this section, we cover discussion of Fedora virtualization technologies on the
@fedora-virt and @virt-tools lists..
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@fedora-virt list.
  
 
Contributing Writer: [[User:Dale | Dale Bewley]]
 
Contributing Writer: [[User:Dale | Dale Bewley]]
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[http://www.redhat.com/mailman/listinfo/fedora-virt fedora-virt list].
 
[http://www.redhat.com/mailman/listinfo/fedora-virt fedora-virt list].
  
==== KSM Tuning ====
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==== Virt Status Report ====
[[IzikEidus|Izik Eidus]]
 
<ref>http://www.redhat.com/archives/fedora-virt/2009-October/msg00110.html</ref>
 
 
 
" by default enabled and only with 2000 kernel pages... What I am worried about is that users wont use the ksm tunning script and would just run ksm with this 2000 kernel pages - the result would be that ksm will probably merge just the zero pages (that could be alot of memory) and the user might not know
 
 
 
that much more memory can be saved...
 
 
 
 
 
Is it possible to at least make ksm disabled by default? so the users will have to run the ksm tunning script when they want to start ksm?
 
 
 
And if we set it to disabled by default, cant we set the initialized values
 
into more realistic value? (like 1/4 of the memory in the mainline kernels? )
 
"
 
<ref>http://www.kernel.org/doc/Documentation/vm/ksm.txt</ref>
 
 
 
[[MarkMcLoughlin|Mark McLoughlin]]
 
<ref>http://www.redhat.com/archives/fedora-virt/2009-October/msg00112.html</ref>
 
 
 
"ksm is disabled by default currently"
 
 
 
"Here's the logic we have in the init script<ref>http://gitorious.org/ksm-control-scripts/ksm-control-scripts</ref>:
 
 
 
<pre>
 
  # unless KSM_MAX_KERNEL_PAGES is set, let ksm munch up to half of total memory.
 
  default_max_kernel_pages () {
 
      local total pagesize
 
      total=`awk '/^MemTotal:/ {print $2}' /proc/meminfo`
 
      pagesize=`getconf PAGESIZE`
 
      echo $[total * 1024 / pagesize / 2]
 
  }
 
</pre>
 
 
 
 
[[JustinForbes|Justin Forbes]]
 
[[JustinForbes|Justin Forbes]]
<ref>http://www.redhat.com/archives/fedora-virt/2009-October/msg00115.html</ref>
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posted<ref>http://www.redhat.com/archives/fedora-virt/2009-December/msg00056.html</ref> a Fedora virtualization status report.
 +
Justin pointed out F13 bugs<ref>http://fedoraproject.org/wiki/Virtualization_bugs</ref> now include Important and Pony classifications in addition to Blocker and Target.
  
"There are actually 2 init scripts.  One to turn on ksm, and one for tuning.
+
<references />
The actual ksm init script simply makes sure ksm is turned on in the kernel
 
and sets max_kernel_pages to half of system memory.  The ksmtuned script is
 
a bit more involved."
 
  
[[MarkMcLoughlin|Mark McLoughlin]]
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==== RHEL and Fedora Virtualization Feature Parity ====
<ref>http://www.redhat.com/archives/fedora-virt/2009-October/msg00119.html</ref>
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Robert Day wondered how the virtualization features<ref>http://www.redhat.com/virtualization/rhev/</ref> of Red Hat Enterprise Linux 5.4
"For Fedora 13, it'll be off by default in the kernel and the recommended
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compared to Fedora 12.
way of switching it on is with 'chkconfig ksm on'
 
  
For Fedora 12, it's on by default in the kernel, 'chkconfig ksm on' just
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[[DanielBerrange|Daniel Berrange]]
changes max pages and the only way of disabling it is by manually
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explained<ref>http://www.redhat.com/archives/fedora-virt/2009-December/msg00040.html</ref>
writing zero to {{filename|/sys/kernel/mm/ksm/run}}"
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"The KVM based virtualization in RHEL-5.4 is not nearly so far behind
 +
Fedora as you might think. The {{package|libvirt}} mgmt stack in RHEL-5.4 was
 +
rebased to be near parity with [[Releases/11|Fedora 11]], and KVM in RHEL-5.4 is
 +
also pretty close to that using what's best described as a hybrid of
 +
kvm-83 and kvm-84."
  
"We'll probably end up with this behaviour in F12 updates at some point
+
<references />
anyway when 2.6.32 is pulled in"
 
  
[[JustinForbes|Justin Forbes]]
 
"The limit to half of total memory is because ksm pages are unswappable at
 
this time.  To be fixed in a future kernel."
 
  
 +
====  ====
 
<references />
 
<references />
  
=== Virtualization Tools List ===
+
==== ====
This section contains the discussion happening on the
 
[http://www.redhat.com/mailman/listinfo/virt-tools-list virt-tools-list list].
 
 
 
==== libosinfo Revisited ====
 
[[ArjunRoy|Arjun Roy]]
 
revived<ref>http://www.redhat.com/archives/virt-tools-list/2009-October/msg00091.html</ref>
 
discussion of a library to track details of OS distributions for use by tools
 
such as {{package|python-virtinst}} and <code>virt-inspector</code>. LibOSinfo was first proposed<ref>http://fedoraproject.org/wiki/FWN/Issue180#libosinfo:_Library_for_Virt_OS.2Fdistro_Metadata</ref>
 
by [[ColeRobinson|Cole Robinson]].
 
 
 
 
<references />
 
<references />

Latest revision as of 18:09, 18 December 2009



Virtualization

In this section, we cover discussion of Fedora virtualization technologies on the @fedora-virt list.

Contributing Writer: Dale Bewley

Fedora Virtualization List

This section contains the discussion happening on the fedora-virt list.

Virt Status Report

Justin Forbes posted[1] a Fedora virtualization status report. Justin pointed out F13 bugs[2] now include Important and Pony classifications in addition to Blocker and Target.

RHEL and Fedora Virtualization Feature Parity

Robert Day wondered how the virtualization features[1] of Red Hat Enterprise Linux 5.4 compared to Fedora 12.

Daniel Berrange explained[2] "The KVM based virtualization in RHEL-5.4 is not nearly so far behind Fedora as you might think. The Package-x-generic-16.pnglibvirt mgmt stack in RHEL-5.4 was rebased to be near parity with Fedora 11, and KVM in RHEL-5.4 is also pretty close to that using what's best described as a hybrid of kvm-83 and kvm-84."