Is there a Fedora equivalent to Ubuntu's Linux-Image-Virtual kernel?

[Fernando Cassia]

Is there a virtualized guest kernel for Fedora as there is
Linux-Image-Virtual for Ubuntu?
http://askubuntu.com/questions/257416/what-are-practical-advantages-of-using...

Thanks in advance...
FC

[Reindl Harald]

Am 24.09.2013 17:37, schrieb Fernando Cassia:
> Is there a virtualized guest kernel for Fedora as there is Linux-Image-Virtual for Ubuntu?
> http://askubuntu.com/questions/257416/what-are-practical-advantages-of-using...

no

it's not worth the maintaince burden because the only
difference is the install size - kernel drivers are
modules and not loaded

loaded modules froma production server (exluded iptables because
they are unusual high here due our FW rules)

vmw_balloon            13415  0
vmxnet3                49572  0
vmw_vmci               61726  0
crc32_pclmul           13113  0
crc32c_intel           22079  0
ghash_clmulni_intel    13259  0
vmw_pvscsi             22858  7

crc32_pclmul, crc32c_intel and ghash_clmulni_intel are Intel AES-NI releated

[Fernando Cassia]

On Tue, Sep 24, 2013 at 11:42 AM, Reindl Harald wrote:
> it's not worth the maintaince burden because the only
> difference is the install size - kernel drivers are
> modules and not loaded

Thanks Reindl!
Very much appreciated.

FC

[Matthew Miller]

On Tue, Sep 24, 2013 at 11:37:32AM -0400, Fernando Cassia wrote:
> Is there a virtualized guest kernel for Fedora as there is
> Linux-Image-Virtual for Ubuntu?
> http://askubuntu.com/questions/257416/what-are-practical-advantages-of-using...

No, there isn't, although the Fedora kernel team is looking at creating one
for F21 and beyond. It's mostly a matter of having resources to maintain the
division -- every thing like this has a cost in human time.

As the comment on Ask Ubuntu notes,

So it is considerably smaller in terms of disk space. I'm not aware of any
  tuning for performance or any functional difference that way, I think it's
  just for smaller images.

and, indeed, this is one of the three big things that keeps our Fedora
images from being tiny. (The other two are i18n and docs, which can be
stripped out, but not in an elegant way.)

Our image is already smaller than Ubuntu's, but it'd be nice to have room
to be that small and also have a few more useful utilities.

[poma]

On 24.09.2013 17:37, Fernando Cassia wrote:
> Is there a virtualized guest kernel for Fedora as there is
> Linux-Image-Virtual for Ubuntu?
> http://askubuntu.com/questions/257416/what-are-practical-advantages-of-using...
>
> Thanks in advance...
> FC

Fedora's current kernels are universal, at least official ones.
https://fedoraproject.org/wiki/Virtualization/History

poma

[Fernando Cassia]

On Tue, Sep 24, 2013 at 12:02 PM, poma  wrote:
> Fedora's current kernels are universal, at least official ones.
> https://fedoraproject.org/wiki/Virtualization/History

Thanks poma.

I was thinking of ways to get a slightly better performance when running
Fedora virtualized under a Windows host, and using Virtualbox, not Xen.

FC

[Reindl Harald]

Am 24.09.2013 18:59, schrieb Fernando Cassia:
> On Tue, Sep 24, 2013 at 12:02 PM, poma <[e-mail] wrote:
> Fedora's current kernels are universal, at least official ones.
> https://fedoraproject.org/wiki/Virtualization/History
>
> I was thinking of ways to get a slightly better performance when running Fedora virtualized under a Windows host,
> and using Virtualbox, not Xen

they other direction works better
why?

a linux OS with a modern filesystem can not do much on top
of NTFS and other design mistakes in windows - in the
other direction the Linux host can do much because it
controls the hardware and scheduler

[Fernando Cassia]

On Tue, Sep 24, 2013 at 1:30 PM, Reindl Harald wrote:
> a linux OS with a modern filesystem can not do much on top
> of NTFS and other design mistakes in windows

It's used for CPU bound tasks with network and USB I/O not very much hard
disk i/o, so the impact on the NTFS layer on the host is likely not big.

The thinner the Linux kernel, the better, I think, ie framebuffer video,
for starters

FC

[Reindl Harald]

Am 24.09.2013 19:42, schrieb Fernando Cassia:
> On Tue, Sep 24, 2013 at 1:30 PM, Reindl Harald <[e-mail] > wrote:
> a linux OS with a modern filesystem can not do much on top
> of NTFS and other design mistakes in windows
>
> It's used for CPU bound tasks with network and USB I/O not very much hard disk i/o

also the COU is *far* better utilized by Linux
search for "Kernel AVX"

http://www.phoronix.com/scan.php?page=news_item&px=MTI1Njc

also on newest Intel CPU's
http://lwn.net/Articles/534758/

in case of hardware support Windows is laughable compared
> The thinner the Linux kernel, the better, I think, ie framebuffer video, for starters

the kernel *is* thin

besides disk space the not loaded/used modules doe snot matter
so no, in case of pure peformance it does not matter

[poma]

On 24.09.2013 18:59, Fernando Cassia wrote:
> I was thinking of ways to get a slightly better performance when running
> Fedora virtualized under a Windows host, and using Virtualbox, not Xen.
>
> FC

In terms of performance you are probably using virtio modules, already.
Even if you don't innotek's hw emulation is quite comparable to the
virtio solution.
Of course there's always room for improvement. :)

poma