[Discuss] Virt-Manager

[markw at mohawksoft.com (markw at mohawksoft.com)]

Try installing qemu packages



markw at snoopy:~$ apt list --installed  | grep -i kvm

WARNING: apt does not have a stable CLI interface. Use with caution in
scripts.

qemu-kvm/focal-security,now 1:4.2-3ubuntu6.17 amd64 [installed,upgradable
to: 1:4.2-3ubuntu6.18]
markw at snoopy:~$ apt list --installed  | grep -i qemu

WARNING: apt does not have a stable CLI interface. Use with caution in
scripts.

aqemu/focal,now 0.9.2-2.3build1 amd64 [installed]
ipxe-qemu-256k-compat-efi-roms/focal,focal,now
1.0.0+git-20150424.a25a16d-0ubuntu4 all [installed,automatic]
ipxe-qemu/focal-updates,focal-updates,now
1.0.0+git-20190109.133f4c4-0ubuntu3.2 all [installed,automatic]
libvirt-daemon-driver-qemu/focal-updates,now 6.0.0-0ubuntu8.14 amd64
[installed,automatic]
qemu-block-extra/focal-security,now 1:4.2-3ubuntu6.17 amd64
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu-efi-aarch64/focal-updates,focal-updates,focal-security,focal-security,now
0~20191122.bd85bf54-2ubuntu3.3 all [installed]
qemu-efi-arm/focal-updates,focal-updates,focal-security,focal-security,now
0~20191122.bd85bf54-2ubuntu3.3 all [installed]
qemu-kvm/focal-security,now 1:4.2-3ubuntu6.17 amd64 [installed,upgradable
to: 1:4.2-3ubuntu6.18]
qemu-system-arm/focal-security,now 1:4.2-3ubuntu6.17 amd64
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu-system-common/focal-security,now 1:4.2-3ubuntu6.17 amd64
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu-system-data/focal-security,focal-security,now 1:4.2-3ubuntu6.17 all
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu-system-gui/focal-security,now 1:4.2-3ubuntu6.17 amd64
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu-system-x86/focal-security,now 1:4.2-3ubuntu6.17 amd64
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu-utils/focal-security,now 1:4.2-3ubuntu6.17 amd64
[installed,upgradable to: 1:4.2-3ubuntu6.18]
qemu/focal-security,now 1:4.2-3ubuntu6.17 amd64 [installed,upgradable to:
1:4.2-3ubuntu6.18]


> When I try to do this again, this is the text in the virt-manager GUI
> that comes up as soon as I select the icon to create a new virtual
> machine:
>
> "Warning: KVM is not available. This may mean the KVM package is not
> installed, or the KVM kernel modules are not loaded. Your virtual
> machine may perform poorly."
>
> FWIW, when I did this for the second time last night, it took an hour
> and a half just to install the image (since deleted).
>
> Don't know if the info below will help:
>
> Just now, running ->???????? ~$ lspci | grep -i virtio?? had no results
>
> /var/log/dmesg no such file or directory
>
> $ sudo dmidecode -s system-manufacturer
> Hewlett-Packard
>
> $ sudo dmidecode -s system-product-name
> CQ5826
>
>
> On 10/20/21 4:25 PM, markw at mohawksoft.com wrote:
>> Let me back up.
>>
>> QEMU is the actual emulation software. KVM is a management layer on top
>> of
>> that. lib-virt AFAIK work on top of KVM. The virt-manager package sits
>> on
>> top of that.
>>
>> Couple things. "Paravirtualization" is what you really want. You want
>> x86[_64] code running on x86[_86] hardware. QEMU will use the
>> virtualization and isolation features of the kernel to run the software
>> "as is" and trap privileged instructions. You can get "near native"
>> speed.
>>
>> You also want to use the VirtIO drivers from within the VM
>>
>> [16:08:36] dut:~ # lspci | grep -i virtio
>> 00:03.0 Ethernet controller: Red Hat, Inc. Virtio network device
>> 00:06.0 Communication controller: Red Hat, Inc. Virtio console
>> 00:07.0 SCSI storage controller: Red Hat, Inc. Virtio block device
>> 00:08.0 Unclassified device [00ff]: Red Hat, Inc. Virtio memory balloon
>> 00:0b.0 SCSI storage controller: Red Hat, Inc. Virtio block device
>> 00:0c.0 SCSI storage controller: Red Hat, Inc. Virtio block device
>> 00:0d.0 SCSI storage controller: Red Hat, Inc. Virtio block device
>>
>> [16:18:04] dut:~ # grep Hypervisor /var/log/dmesg
>> [    0.000000] Hypervisor detected: KVM
>>
>> [16:20:12] dut:~ # dmidecode -s system-manufacturer
>> QEMU
>> [16:20:27] dut:~ # dmidecode -s system-product-name
>> Standard PC (i440FX + PIIX, 1996)
>>
>> This means that I am not emulating a controller. I/O to the network or
>> disk directly interfaces to the hypervisor's system without emulating
>> something stupid like emulex, intel, or etc.
>>
>> The qcow2 is a copy-on-write (cow) format. Every write to the qcow2 file
>> is multiplied. If you use a raw file, you lose some of the flexibility
>> of
>> the qcow2 format, but speed is improved.
>>
>> You can shut down the VM and use "qemu-image convert" to go from qcow2
>> to
>> raw.
>>
>> You can edit the vm definition using virt-manager, edit the disk, and
>> click the xml tab, change "type" from "qcow2" to "raw" and update the
>> file
>> name.
>>
>>> Virt-manager created it as a .qcrow2 by default, did not know what that
>>> was. There was also an indication that 'the KVM package' was not
>>> installed and as a result, it would run slowly. I would have expected
>>> the installation of virt-manager to also pull in all required
>>> dependencies. Debian does not provide a package named 'kvm' and
>>> searching using that string under Description & Name with Synaptic,
>>> found no such packages that looked like it would install KVM.
>>>
>>> I believe the file system it is using, is ext4.
>>>
>>>
>>> On 10/20/21 3:00 PM, markw at mohawksoft.com wrote:
>>>> I use KVM all the time and manage it with virt-manager.
>>>>
>>>> (1) Make sure that network and disk use VirtIO para-virtual driver, do
>>>> not
>>>> emulate physical devices.
>>>>
>>>> (2) Don't use qcow2, its really slow. Pre-allocate your boot drive:
>>>>
>>>> touch myboot.raw
>>>> truncate -s SIZE myboot.raw
>>>>
>>>> The above will let you define a large thin-provisioned disk.
>>>>
>>>> If you have LVM or ZFS you can create a logical volume or zvol, but I
>>>> think the thin provisioned "sparse" file may be faster because of the
>>>> double caching.
>>>>
>>>>> On 10/18/21 9:20 PM, Edward wrote:
>>>>>> I missed a setting, found it afterwards, it defaults to Virtual
>>>>>> Network
>>>>>> (NAT) and the box to start it automatically was initially not
>>>>>> checked.
>>>>>>
>>>>>> It's working now.
>>>>>>
>>>>> And it (take your pick):
>>>>>
>>>>>     * is slow as molasses
>>>>>     * runs at a snail's pace
>>>>>
>>>>>
>>>>> Not even worth using. Gnome Boxes on Fedora 33 ran far better and
>>>>> faster
>>>>> than Virt Manager does on Debian.
>>> _______________________________________________
>>> Discuss mailing list
>>> Discuss at lists.blu.org
>>> http://lists.blu.org/mailman/listinfo/discuss
>>>
>>
>
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