There is another issue, there is no way to change io speed from UI for system vm's guest network(nic2) in basic network model, which will impact all the template downloading in a negatively way. We'd better don't throttle system vm's io speed by default, or at least give admin the way to change the io speed.
> -----Original Message----- > From: Edison Su [mailto:edison...@citrix.com] > Sent: Friday, August 09, 2013 11:27 AM > To: dev@cloudstack.apache.org > Subject: RE: [DISCUSS] KVM io throttling > > > > > -----Original Message----- > > From: Wido den Hollander [mailto:w...@widodh.nl] > > Sent: Friday, August 09, 2013 2:41 AM > > To: dev@cloudstack.apache.org > > Subject: Re: [DISCUSS] KVM io throttling > > > > > > > > On 08/09/2013 02:05 AM, Edison Su wrote: > > > Hi All, > > > For basic network, the io limit for guest network(nic 2) is > > > 200MB/s, we > > set the io limit on kvm host as: > > > > > > > I think you mean 200Mbit/s? > Oh, I see, it's 200Mb/s. > > > > > </interface> > > > <interface type='bridge'> > > > <source bridge='cloudbr0'/> > > > <mac address='06:45:c4:00:00:0c'/> > > > <model type='virtio'/> > > > <bandwidth> > > > <inbound average='25600' peak='25600'/> <outbound average='25600' > > > peak='25600'/> </bandwidth> </interface> > > > > > > > > > From libvirt doc(http://libvirt.org/formatnetwork.html), it says > > > above unit > > is KB/s, but per my testing, it sounds like it's Kb/s. Is there > > anybody have the same issue? > > > > > > > No, my testing tells me it's is KB/sec (KiloByte). > On centos 6.3 + libvirt 0.9.10, the number doesn't match: > With the following simple test: > > dd if=/dev/zero of=some-nfs-mount-point bs=1M count=10 I can get 104 > MB/s if nic2 speed is unlimited, while only get 1MB/s, if nic2 is configured > with <bandwidth> > <inbound average='25600' peak='25600'/> > <outbound average='25600' peak='25600'/> > </bandwidth> > > Maybe it's an issue on Centos 6.3? > > > > > > My libvirt version is 0.9.10 on Centos 6.3. > > > > > > > My libvirt version is 1.0.6 under Ubuntu 12.04 using the Cloud Archive > > for OpenStack Havana from Canonical: > > https://wiki.ubuntu.com/ServerTeam/CloudArchive > > > > Wido
