<div dir="ltr">Hi Jatin,<div><br></div><div>The RedHat documentation on this is extremely helpful. It's so helpful that I use it as a reference on completely different distributions.</div><div><br></div><div>VMWare does a pretty good job of guiding you and giving you defaults that are sensible. With Libvirt/QEMU/KVM, you need to get an idea of those and enable them yourself.</div><div><br></div><div>For example, I see that you are using qcow2 files, but if you don't need the features it provides, then using block devices (usually logical volumes in a volume group) directly for VM disks may be significantly faster. It also depends on how caching is configured. The manuals will step you through all of that. Pay special attention to storage, because it's the first bottleneck a lot of applications hit.</div><div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px"><br class="">Check out the manuals under the virtualization section here: <a href="https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/">https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/</a></div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px"><br></div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px">Specifically: <a href="https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Virtualization_Tuning_and_Optimization_Guide/index.html">https://access.redhat.com/documentation/en-US/Red_Hat_Enterprise_Linux/7/html/Virtualization_Tuning_and_Optimization_Guide/index.html</a></div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px"><br></div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px">Good luck!</div><div style="color:rgb(34,34,34);font-family:arial,sans-serif;font-size:small;font-style:normal;font-variant:normal;font-weight:normal;letter-spacing:normal;line-height:normal;text-align:start;text-indent:0px;text-transform:none;white-space:normal;word-spacing:0px">Nikki</div><br></div></div><div class="gmail_extra"><br><div class="gmail_quote">On Tue, Apr 14, 2015 at 9:18 AM, Matt Schumacher <span dir="ltr"><<a href="mailto:matt.s@aptalaska.com" target="_blank">matt.s@aptalaska.com</a>></span> wrote:<br><blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex">
<div bgcolor="#FFFFFF" text="#000000">
Jatin,<br>
<br>
Using qemu without the virtio scsi and nic drivers is like running
vmware with ide disks and e1000 nic instead of LSI disks and vmxnet3
nics, it forces the system to emulate completely different hardware.<br>
<br>
In linux the virtio drivers are implemented in the kernel, so you
either need a new kernel or the virtio kernel modules. I'm not sure
which for RHEL5, but I suspect you can get what you need with the
kmod-virtio package, then rebuilding the initrd image to load the
modules at boot.<br>
<br>
Keep in mind that sda will change to vda, which on some linux
distros requires updates to the bootloader and inittab, but redhat
uses filesystem labels if I remember correctly, so it should just
work.<br>
<br>
Please let us know how the benchmarks look after you get virtio
working, I'm curious...<br>
<br>
schu<div><div class="h5"><span></span><br>
<br>
<br>
<div>On 4/14/2015 5:33 AM, Jatin Davey
wrote:<br>
</div>
</div></div><blockquote type="cite"><div><div class="h5">
<font face="Times New Roman">Thanks Dominique & Daniel.<br>
<br>
Looks like i need to upgrade my VMs kernel to make it aware of
virtio.<br>
<br>
Found this information from this link:<br>
<br>
<a href="http://wiki.libvirt.org/page/Virtio#Disk_.28block.29_device_driver" target="_blank">http://wiki.libvirt.org/page/Virtio#Disk_.28block.29_device_driver</a><br>
<br>
I tried without upgrading the Kernel and as soon as i start my
VM it got into Kernel Panic. I will try using virtio after
upgrading my VMs kernel.<br>
<br>
Thanks for all the responses and pointers.<br>
<br>
Thanks<br>
Jatin<br>
</font><br>
<div>On 4/14/2015 5:08 PM, Dominique
Ramaekers wrote:<br>
</div>
<blockquote type="cite">
<pre>Please read: <a href="https://libvirt.org/formatdomain.html" target="_blank">https://libvirt.org/formatdomain.html</a>
-----Oorspronkelijk bericht-----
Van: Jatin Davey [<a href="mailto:jashokda@cisco.com" target="_blank">mailto:jashokda@cisco.com</a>]
Verzonden: dinsdag 14 april 2015 13:39
Aan: Daniel P. Berrange
CC: Dominique Ramaekers; <a href="mailto:libvirt-users@redhat.com" target="_blank">libvirt-users@redhat.com</a>
Onderwerp: Re: [libvirt-users] VM Performance using KVM Vs. VMware ESXi
On 4/14/2015 4:58 PM, Daniel P. Berrange wrote:
</pre>
<blockquote type="cite">
<pre>On Tue, Apr 14, 2015 at 04:53:52PM +0530, Jatin Davey wrote:
</pre>
<blockquote type="cite">
<pre>On 4/14/2015 4:42 PM, Dominique Ramaekers wrote:
</pre>
<blockquote type="cite">
<pre>About Spice: I think it’s good practice to use spice because it
improves the performance of the VM in general by improving screen
performance. If your VM is constantly displaying output, you’ll
probably will notice a difference.
</pre>
</blockquote>
<pre>[Jatin] Ok, This is not my concern as of now. I will take a look at
it sometime later.
</pre>
<blockquote type="cite">
<pre>About virtio: You can see it in the settings. Better yet, it’s in
your XML. If you post your XML, we can take a look…
</pre>
</blockquote>
<pre>Here is the xml associated with my VM:
********************************
<domain type='kvm'>
<devices>
<emulator>/usr/libexec/qemu-kvm</emulator>
<disk type='file' device='disk'>
<driver name='qemu' type='qcow2' cache='none'/>
<source file='/var/lib/libvirt/images/****.qcow2'/>
<target dev='hda' bus='ide'/>
<address type='drive' controller='0' bus='0' target='0' unit='0'/>
</disk>
</pre>
</blockquote>
<pre>This disk is configured to use IDE, so performance of anything that
does disk I/O is going to be terrible. You really want to be using virtio.
</pre>
<blockquote type="cite">
<pre> <interface type='bridge'>
<mac address='52:54:00:c9:58:c9'/>
<source bridge='br332'/>
<address type='pci' domain='0x0000' bus='0x00' slot='0x03' function='0x0'/>
</interface>
</pre>
</blockquote>
<pre>This doesn't have any model listed at all, so it will be falling back
to a generic emulated NIC. Again performance of this is likely going
to be terrible for anything doing network I/O. You want to be using
virtio for this too.
Regards,
Daniel
</pre>
</blockquote>
<pre>How do i make use of virtio for the both disk and network that you have mentioned above ?
Any pointers to it would be helpful.
Thanks
Jatin
</pre>
</blockquote>
<br>
<br>
<fieldset></fieldset>
<br>
</div></div><span class=""><pre>_______________________________________________
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</span></blockquote>
<br>
</div>
<br>_______________________________________________<br>
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<a href="https://www.redhat.com/mailman/listinfo/libvirt-users" target="_blank">https://www.redhat.com/mailman/listinfo/libvirt-users</a><br></blockquote></div><br><br clear="all"><div><br></div>-- <br><div class="gmail_signature"><div dir="ltr">Nikki VonHollen<div><a href="https://goto.google.com/goobuntu" target="_blank">Goobuntu Team</a></div><div>540-553-1904</div></div></div>
</div>