Am 17.06.2011 13:39, schrieb al pat: > Hi Kevin, > > Thanks! > > Yes, one disk is visible in guest as sdb (partitioned to sdb1), > mounted and I write to it. > > The virtio disk is visible as /dev/vda, (partitioned to vda1), mounted > and I write to it.
Then it's using virtio-blk. > Kernel log on guest - do you mean dmesg? > > I was trying to trace through the virt io calls to confirm. and > determine the invocation sequence. > > My lspci output: > 00:00.0 Host bridge: Intel Corporation 440FX - 82441FX PMC [Natoma] (rev 02) > 00:01.0 ISA bridge: Intel Corporation 82371SB PIIX3 ISA [Natoma/Triton II] > 00:01.1 IDE interface: Intel Corporation 82371SB PIIX3 IDE [Natoma/Triton II] > 00:01.2 USB Controller: Intel Corporation 82371SB PIIX3 USB > [Natoma/Triton II] (rev 01) > 00:01.3 Bridge: Intel Corporation 82371AB/EB/MB PIIX4 ACPI (rev 03) > 00:02.0 VGA compatible controller: Cirrus Logic GD 5446 > 00:03.0 Ethernet controller: Qumranet, Inc. Unknown device 1000 > 00:04.0 RAM memory: Qumranet, Inc. Unknown device 1002 > 00:06.0 SCSI storage controller: Qumranet, Inc. Unknown device 1001 This unknown device 1001 is your virtio-blk disk. Kevin > > lspci -k --- to show kernel drivers associated with the device does > not work in the guest. > > Thanks > a > > > On Fri, Jun 17, 2011 at 7:15 AM, Kevin Wolf <kw...@redhat.com> wrote: >> Am 16.06.2011 20:57, schrieb al pat: >>> I have posted this on kvm alias, but have not heard back. seeing some >>> inputs. >>> >>> seeking some pointers/guidance as to how to determine virtio is being >>> used... >>> >>> I configured a VM to use block device with if=virtio (create a 1GB >>> disk using dd I exported this disk to the VM and am now doing scp from >>> host to the >>> guest after creating partition/mkfs. >>> >>> I created another 1GB disk and export it as a IDE disk. I use the same >>> scp command from host to guest after creating partition/mkfs. >>> >>> I am trying to determine if my block IO is indeed using virtio in the >>> first case. >>> >>> Empirically, I observe that with if=virtio, the throughput is about >>> 30% more (in terms of mbps) and time taken is about 40% less than >>> for the case where I passed the disk as a IDE disk. >>> >>> My scp happens over virbr0 interface (and currently I am not concerned >>> if networking is using virtio) >>> >>> How do I confirm that virtio is being used? Are there any debugs that >>> I can enable to do that. >> >> Have a look at the guest kernel logs, lspci output or just at the device >> name: IDE disks are called /dev/sda etc. whereas virtio-blk disks are >> called /dev/vda etc. >> >> Kevin >>
