Bugs item #1998355, was opened at 2008-06-20 02:11 Message generated for change (Comment added) made by jessorensen You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1998355&group_id=180599 Please note that this message will contain a full copy of the comment thread, including the initial issue submission, for this request, not just the latest update. Category: None Group: None >Status: Closed >Resolution: Out of Date Priority: 5 Private: No Submitted By: Joshua Rosen (bjrosen) Assigned to: Nobody/Anonymous (nobody) Summary: IO Performance Initial Comment: Is there any way of mapping a host's directory into a KVM VM similar to VMware's Shared Folder feature? I've been benchmarking the performance of NCVerilog under various VMs. The performance of KVM when using a virtual disk is excellent, in fact it's better than VMware Server or VMware Workstation, however if you use an NFS mounted host directory the performance is unspeakably awful. An NFS mounted directory under VMware Server 2.0 (Beta 2) is also slow but it's still significantly better than KVM. Using a Shared Folder with VMware Workstation eliminates the IO bottleneck, the performance there is about the same as accessing a virtual disk. The system that I did these benchmarks on is a 3GHz Core2 with 8G of RAM. VMware was running under CentOS5.1 with a 2.6.23.7 kernel. KVM is running on Fedora 9 with a 2.6.25.xx kernel. The Verilog simulation times for my test suite are as follows, Native 06:34 VM Server 2, virtual disk 08:05 VM Server 2, NFS 18:37 VM Workstation, shared folder 08:14 KVM, Virtual disk 07:42 KVM, NFS 38:36 ---------------------------------------------------------------------- >Comment By: Jes Sorensen (jessorensen) Date: 2010-11-18 11:16 Message: Per previous comment, bug is out of date. There are a number of solutions in upstream and better performance. If you still feel this is an issue, please feel free to open a new bug in Launchpad. Thanks, Jes ---------------------------------------------------------------------- Comment By: Jes Sorensen (jessorensen) Date: 2010-08-19 12:18 Message: Hi, Did this get resolved? If so would you mind closing this bug. If I don't hear back, I will assume it is fixed and close it at some point :) Thanks, Jes ---------------------------------------------------------------------- Comment By: Joshua Rosen (bjrosen) Date: 2008-06-22 15:54 Message: Logged In: YES user_id=39829 Originator: YES I've tried the following command line, it brings up the VM but I can't configure the NIC, there is an error message about vlan 0. qemu-kvm -M pc -m 512 -smp 1 -monitor pty -net nic,macaddr=a0:1e:37:84:b1:da,model=virtio -boot c -hda /home/xen/panther Warning: vlan 0 is not connected to host network I've also tried the following, but the qemu-ifup command is missing an argument qemu-kvm -M pc -m 512 -smp 1 -monitor pty -net nic,macaddr=a0:1e:37:84:b1:da,model=virtio -net tap,script=/etc/xen/qemu-ifup -boot c -hda /home/xen/panther config qemu network with xen bridge for tap0 Incorrect number of arguments for command Usage: brctl addif <bridge> <device> add interface to bridge char device redirected to /dev/pts/3 ---------------------------------------------------------------------- Comment By: Dor Laor (thekozmo) Date: 2008-06-22 08:08 Message: Logged In: YES user_id=2124464 Originator: NO Example cmdline: ./qemu/x86_64-softmmu/qemu-system-x86_64 -boot c -drive file=/images/xpbase.qcow2,if=ide,cache=on,format=qcow2,boot=on -m 384 -net nic,macaddr=a0:1e:37:84:b1:da,model=virtio -net tap,script=/etc/kvm/qemu-ifup -snapshot btw: you can use 'ps' to discover libvirt cmdline ---------------------------------------------------------------------- Comment By: Joshua Rosen (bjrosen) Date: 2008-06-22 03:18 Message: Logged In: YES user_id=39829 Originator: YES How do I use virtio-net instead of virtio-blk? I've been launching the VM using virt-manager which has no options. KVM doesn't have a MAN page so I have no idea about how to launch the VM using the CLI. Would you please give me specific step by step instructions. Thanks, ---------------------------------------------------------------------- Comment By: Joshua Rosen (bjrosen) Date: 2008-06-21 16:28 Message: Logged In: YES user_id=39829 Originator: YES How do I use virtio-net instead of virtio-blk? I've been launching the VM using virt-manager which has no options. KVM doesn't have a MAN page so I have no idea about how to launch the VM using the CLI. Would you please give me specific step by step instructions. Thanks, ---------------------------------------------------------------------- Comment By: Dor Laor (thekozmo) Date: 2008-06-21 15:45 Message: Logged In: YES user_id=2124464 Originator: NO If you don't boot from virtio-blk there is no need for this configuration. Just use virtio-net in order to boost nfs accesses. ---------------------------------------------------------------------- Comment By: Joshua Rosen (bjrosen) Date: 2008-06-21 01:29 Message: Logged In: YES user_id=39829 Originator: YES The instructions for setting up virtio are a little confusing. I have a CentOS5 VM on Fedora 9. F9 uses the 2.6.25 kernel. The wiki says to edit /etc/initramfs-tools/modules however it doesn't say whether this file is on the host or the guest. There is no /etc/initramfs-tools directory on either. Would someone please clarify the procedure for adding a virtio NIC on an F9 host. ---------------------------------------------------------------------- Comment By: Dor Laor (thekozmo) Date: 2008-06-20 23:58 Message: Logged In: YES user_id=2124464 Originator: NO Did you use virtio nic when testing kvm with NFS? If not, do try, it should boost your performance. ---------------------------------------------------------------------- You can respond by visiting: https://sourceforge.net/tracker/?func=detail&atid=893831&aid=1998355&group_id=180599 -- To unsubscribe from this list: send the line "unsubscribe kvm" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
