Re: Bandwith limit on guests

[Andrija Panic <an...@gmail.com>]

During your experiment, you can always confirm what speeds are set on each
VNET/NIC of the VM - this below, is 1Gbps limit (multiple 131072 by 8KB =
1Gbps)


root@XXXXX:~# virsh domiflist i-2-5-VM
Interface  Type       Source     Model       MAC
-------------------------------------------------------
vnet0      bridge     brvx-812   virtio      02:00:05:6a:00:01

root@XXXXX:~# virsh domiftune i-2-5-VM vnet0
inbound.average: 131072
inbound.peak   : 131072
inbound.burst  : 0
outbound.average: 131072
outbound.peak  : 131072
outbound.burst : 0
Or if

root@XXXXXX:~# tc class show dev vnet0
class htb 1:1 root leaf 2: prio 0 rate 1049Mbit ceil 1049Mbit burst 1441b
cburst 1441b

Not very readable though...


My experience so far (as Angus already explained)

- Define network speed on Compute Offerings, don't really on global config
- this set inbound/outbound speed on the NIC of the VM (vnetXYZ)
- Define network speed on the Network Offering (Network offerings for VPC)
- again dont rely on global config...this set inbound/outbound speed of the
Public VR NIC - BUT ALSO ON ALL OHTER VR NIC...

Anyone knows if possible to have public VR NIC to i.e. 100 Mbps, while all
internal interfaces are 1Gbps ? I didn't find it possible so far...I see
that all internal NIC always inherit pulbic NIC speed/traffic shaping

Best
Andrija


On 31 October 2017 at 18:42, Paul Angus <pa...@shapeblue.com> wrote:

> Hi Imran,
>
> I think there are a couple of issues here:
>
> 1. The egress bandwidth from VMs is controlled by the Compute Offering not
> the VR Network offering (that controls egress out of the public face of the
> VR)
> 2. The fallback global setting for vm egress bandwidth is
> vm.network.throttling.rate (if not set in the compute offering)
> 3. to set something as unlimited, you would use '-1' not '0'
>
> I hope that this helps
>
>
> Kind regards,
>
> Paul Angus
>
> paul.angus@shapeblue.com
> www.shapeblue.com
> 53 Chandos Place, Covent Garden, London  WC2N 4HSUK
> @shapeblue
>
>
>
>
> -----Original Message-----
> From: Eric Green [mailto:eric.lee.green@gmail.com]
> Sent: 30 October 2017 19:05
> To: users@cloudstack.apache.org
> Subject: Re: Bandwith limit on guests
>
> Did you try the same test from the exact same physical host that one of
> the guests are running on? There may be congestion between the Cloudstack
> network and the NFS network.
>
> I just tested this by creating a compute offering that had the 200Mbit
> limit and assigning it to an instance. I mounted a NFS directory, and
> dding' a large file in that directory. I got the 23 mbyte/sec throughput I
> expected. I then shut the instance down, reassigned it to another compute
> offering without the limit, started it back up, and dd'ed that large file.
> I got the 200mbyte/sec throughput that I expected from this specific NFS
> server.
>
> How exactly are you setting network and VM throttling? Are you talking
> about in the Global Settings? If so, note that any limit set here (even
> infinite -- i.e., zero) is overridden by the values in the service offering
> if the service offering's values are smaller. Please check your service
> offerings to make sure they don't have throttling values in them. Also make
> sure that you put both network.throttling.rate and
> vm.network.throttling.rate back down to zero.
>
> Note -- I am running Cloudstack 4.9.2. But it should work same as 4.8 here.
>
>
> > On Oct 30, 2017, at 10:56, Imran Ahmed <im...@eaxiom.net> wrote:
> >
> > Hi All,
> >
> > WE are facing a bandwidth problem on our cloudstack guests.
> > (cloudstack 4.8 with KVM  on CentOS)
> >
> > The network and vm throttling was set at 200mbs, and we're seeing a
> > max on the guests of 25MB/sec (just slightly over the throttle).  I
> > set the values to 0, restarted the management server and
> > stopped/started the virtual router.  However, the guests are still only
> seeing 25MB/sec to an NFS share.
> > I performed the same test to the same NFS share on a physical machine
> > and it reached the full gigabit network speed (just over 100MB/sec).
> >
> >
> > Any ideas please?
> >
> > Kind regards,
> >
> > Imran
> >
>
>


-- 

Andrija Panić