Re: [Qemu-discuss] Guest network performance is painfully slow
Cool. If the merge really has completed, that's good to know. Tony On Tue, Aug 19, 2014 at 8:34 AM, Peter Maydell peter.mayd...@linaro.org wrote: On 19 August 2014 16:26, Tony Su ton...@su-networking.com wrote: According to the qemu-kvm page, http://wiki.qemu.org/KVM The upstream merging is still in progress. That page says as of the 1.3 release all qemu-kvm features have been merged into upstream QEMU. It's also had no relevant edits since 2013; in fact hotplug has been implemented in upstream. I would guess that using your distro's KVM packages will incorporate QEMU features as much as possible with emphasis on KVM stability while using QEMU packages focus on QEMU feature stability over KVM. The two are probably nearly the same but needs closer inspection if one of the few significant differences matter to you. No, really, qemu-kvm is dead. -- PMM
Re: [Qemu-discuss] Guest network performance is painfully slow
Unless someone says differently, I believe that doesn't change the likely fact that the main KVM is different than what you are doing and would perform much better. Tony On Sun, Aug 17, 2014 at 8:09 PM, JHM j...@juliohm.com.br wrote: Sorry, I'm taking my first steps with qemu here. The man page for kvm tells me The kvm wrapper script is used to provide compatibility with old qemu-kvm package which has been merged into qemu as of version 1.3. ... which is the the same as runnign qemu-system-x86_64 -enable-kvm. -- Julio H. Morimoto -- j...@juliohm.com.br On Sun, Aug 17, 2014 at 11:51 PM, Tony Su ton...@su-networking.com wrote: Is there some reason why you appear to be running full virtualization qemu? If you don't need special emulation features of regular QEMU, you should instead be running the paravirtualized version (KVM) which will provide vastly better performance. I haven't seen that -enable-kvm flag before, but it likely won't be nearly the same as running KVM itself. Tony On Sun, Aug 17, 2014 at 7:34 PM, JHM j...@juliohm.com.br wrote: Salutations to all members, first off. This is my first post in the discussion group. I searched for this topic, but not much turned up from the archive here. Searching for slow http://lists.nongnu.org/archive/cgi-bin/namazu.cgi?query=slowsubmit=Search!idxname=qemu-discussmax=100result=normalsort=score I would like to ask if anyone else had troubles with the network performance in the guest network. I am running qemu using ubuntu-14.04 as host. The guest is also ubuntu-14.04. In the guest OS, I have a LAMP stack properly configured. Users can reach the apache server inside via a host NATed tap interface. Anything poking the host at port 80 is passed into the private network between the guest/host. This all works well, and seems to be OK. Users can view websites and download files hosted in the guest LAMP. Except, users are getting very limited download speeds. While the host sits on a 100Mbps symmetric up/down link, users are only able to download at 15Kbps or max 30Kbps. I used to have the same setup running natively without QEMU and user download speeds were great. Once I moved the LAMP stack into the virtual machine, this issue came up. The following is the command line used to start up the qemu vm. qemu-system-x86_64 -hda disk1.qcow -m 1G -smp 4 -enable-kvm -netdev tap,id=tap0,ifname=tap0,script=tap-config.sh -device e1000,netdev=tap0 Call me naive here, but is this kind of network performance expected? The guest OS is unusable. -- Julio H. Morimoto -- j...@juliohm.com.br
Re: [Qemu-discuss] Guest network performance is painfully slow
On 18 August 2014 07:09, Tony Su ton...@su-networking.com wrote: Unless someone says differently, I believe that doesn't change the likely fact that the main KVM is different than what you are doing and would perform much better. No, Julio is correct. The KVM functionality was all merged into upstream QEMU, and the separate qemu-kvm project is now dead. If your qemu-kvm binary is not just a wrapper script that runs qemu then it's probably an old and out of date version that should be upgraded. The wrappers are just to enable the KVM functionality, which defaults to off in QEMU, so providing the -enable-kvm command line option is equivalent. In any case, if we were using emulation this would be very obvious because everything would be slow, not just network access. I'm afraid I can't help with the network question, though. thanks -- PMM
Re: [Qemu-discuss] Guest network performance is painfully slow
Why are you using e1000 and not virtio? The virtio drives have significantly better performance Ubuntu should also have native support for them. On 8/17/2014 10:34 PM, JHM wrote: Salutations to all members, first off. This is my first post in the discussion group. I searched for this topic, but not much turned up from the archive here. Searching for slow http://lists.nongnu.org/archive/cgi-bin/namazu.cgi?query=slowsubmit=Search!idxname=qemu-discussmax=100result=normalsort=score http://lists.nongnu.org/archive/cgi-bin/namazu.cgi?query=slowsubmit=Search%21idxname=qemu-discussmax=100result=normalsort=score I would like to ask if anyone else had troubles with the network performance in the guest network. I am running qemu using *ubuntu-14.04 as host*. The *guest is also ubuntu-14.04*. In the guest OS, I have a LAMP stack properly configured. Users can reach the apache server inside via a host NATed tap interface. Anything poking the host at port 80 is passed into the private network between the guest/host. This all works well, and seems to be OK. Users can view websites and download files hosted in the guest LAMP. Except, users are getting very limited download speeds. While the host sits on a 100Mbps symmetric up/down link, users are only able to download at 15Kbps or max 30Kbps. I used to have the same setup running natively without QEMU and user download speeds were great. Once I moved the LAMP stack into the virtual machine, this issue came up. The following is the command line used to start up the qemu vm. qemu-system-x86_64 -hda disk1.qcow -m 1G -smp 4 -enable-kvm -netdev tap,id=tap0,ifname=tap0,script=tap-config.sh -device e1000,netdev=tap0 Call me naive here, but is this kind of network performance expected? The guest OS is unusable. -- Julio H. Morimoto -- j...@juliohm.com.br mailto:j...@juliohm.com.br
