Azure VM Network Bandwidth

July 2017 – Updated with new VPN Gateway types 

In this blog post we look at some network bandwidth tests for a variety of Azure VM sizes.

The tests have been run between two VM’s in the same VNet. Network bandwidth testing has been done with Linux using iperf3 running on CentOS 7.2 and Windows 2016 using the Ntttcp tool.

Both single stream and multi stream tests were used. Of course your actual throughput numbers will vary from the ones seen in the tests below due to a number of factors (OS Type, workload characteristics etc….)

Note:  Microsoft is currently in the process of implementing some Azure Network optimisations:

1. 1. “Receive Side Scaling” – https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-optimize-network-bandwidth
   2. “Accelerated Networking” – https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-accelerated-networking-portal

The table below has been updated to include optimization 1. further updates will follow later in the year.
Entries in green include optimisation 1 “Receive Side Scaling”.

OS	VM Type	# Cores	Single Stream Throughput	‘N’ Streams Throughput (1x #Cores)
CentOS (with 1)	A0 Basic	0.25	10 Mbps	10 Mbps
CentOS (with 1)	A1 Basic	1	100 Mbps	100 Mbps
CentOS (with 1)	A2 Basic	2	200 Mbps	200 Mbps
CentOS (with 1)	A3 Basic	4	400 Mbps	395 Mbps
CentOS (with 1)	A4 Basic	8	805 Mbps	816 Mbps
Windows	A4 Basic	8	737 Mbps	734 Mbps
CentOS (with 1)	A1 Standard	4	500 Mbps	500 Mbps
CentOS (with 1)	A2 Standard	4	500 Mbps	500 Mbps
CentOS (with 1)	A3 Standard	4	1000 Mbps	1000 Mbps
CentOS (with 1)	A4 Standard	8	1990 Mbps	2000 Mbps
CentOS (with 1)	A6 Standard	8	1000 Mbps	1000 Mbps
CentOS (with 1)	A6 Standard	8	2000 Mbps	2000 Mbps
CentOS (with 1)	A1 v2	1	495 Mbps	488 Mbps
Windows	A1 v2	1	411 Mbps	467 Mbps
CentOS (with 1)	A2 v2	2	500 Mbps	492 Mbps
CentOS (with 1)	A4 v2	4	998 Mbps	999 Mbps
CentOS (with 1)	A8 v2	8	1980 Mbps	1910 Mbps
CentOS (with 1)	A8	8	4000 Mbps	4200 Mbps
CentOS (with 1)	A9	16	4550 Mbps	7850 Mbps
CentOS (with 1)	A10	8	3990 Mbps	3995 Mbps
Windows	A10	8	1820 Mbps	3942 Mbps
CentOS (with 1)	A11	16	4410 Mbps	8000 Mbps
CentOS (with 1)	D1 v2	1	750 Mbps	726 Mbps
CentOS (with 1)	D2 v2	2	1500 Mbps	1500 Mbps
CentOS (with 1)	D3 v2	4	3000 Mbps	3000 Mbps
CentOS (with 1)	D4 v2	8	4950 Mbps	6000 Mbps
CentOS (with 1)	D5 v2	16	4840 Mbps	12000 Mbps
CentOS (with 1)	D11 v2	2	1500 Mbps	1500 Mbps
CentOS (with 1)	D12 v2	4	3000 Mbps	3000 Mbps
CentOS (with 1)	D13 v2	8	4210 Mbps	5990 Mbps
CentOS (with 1)	D14 v2	16	4990 Mbps	11900 Mbps
CentOS (with 1)	D15 v2	20	4440 Mbps	15500 Mbps
Windows	D15 v2	20	1002 Mbps	12176 Mbps
CentOS (with 1)	F1	1	750 Mbps	749 Mbps
CentOS (with 1)	F2	2	1500 Mbps	1490 Mbps
CentOS (with 1)	F4	4	2990 Mbps	2995 Mbps
Windows (with 1)	F4	4	928 Mbps	2640 Mbps
CentOS (with 1)	F8	8	3490 Mbps	5990 Mbps
Windows	F8	8	390 Mbps	4388 Mbps
CentOS (with 1)	F16	16	4110 Mbps	11800 Mbps
Windows (with 1)	F16	16	1096 Mbps	8416 Mbps
CentOS (with 1)	G1	2	2000 Mbps	2000 Mbps
CentOS (with 1)	G2	4	3270 Mbps	4000 Mbps
CentOS (with 1)	G3	8	3160 Mbps	8000 Mbps
CentOS (with 1)	G4	16	3970 Mbps	8880 Mbps
Windows	G4	16	1602 Mbps	9488 Mbps
Windows (with 1)	G4	16	1904 Mbps	7856 Mbps
CentOS (with 1)	G5	32	3850 Mbps	13700 Mbps
CentOS (with 1)	NV6	6	4850 Mbps	5970 Mbps
CentOS (with 1)	NV12	12	4760 Mbps	12200 Mbps

Test method

In each CentOS VM:

$ sudo yum -y update          (a very important step !)

Ensure Receive Side Scaling is enabled see:  https://docs.microsoft.com/en-us/azure/virtual-network/virtual-network-optimize-network-bandwidth

$ wget https://iperf.fr/download/fedora/iperf3-3.1.3-1.fc24.x86_64.rpm
$ sudo yum install iperf3-3.1.3-1.fc24.x86_64.rpm

On one VM run iperf in server mode
$ iperf3 -s

On another VM run single stream test:
$ iperf3 -c ip-of-server

For the multiple streams test:
$ iperf3 -c  ip-of-server  -P n

Where n =  number of cores in VM

In each Windows 2016 VM:

Apply the latest Windows updates then download ntttcp from here

On one VM (ip=w.x.y.z) run ntttcp in receiver mode
C:> ntttcp -r -m 1,*,w.x.y.z
&
C:> ntttcp -r -m n,*,w.x.y.z   (for the multi-thread test)
Where n = 8x number of cores in VM

On another VM run single thread test ntttcp in sender mode:
C:> ntttcp -s -m 1,*,w.x.y.z.

For the multi thread test:
C:> ntttcp -s -m n,*,w.x.y.z.

Where n =  the number of cores in VM

Peering VNets (Directly connected)

Testing between VM’s in directly peered VNets showed no noticeable difference.

Peered VNets in the same region

Testing between VM’s indirectly peered via the new gateway types (VPMGW1, 2 & 3) shows bandwidth up to 2.8Gbs a big step forward from the previous gateway types that returned a maximum of  980 Mbps when using the now depreciated ‘High Performance’ gateway.

Gateway Type	Single Stream Throughput	‘N’ Stream Throughput (1x #Cores)
VPNGW1	700 Mbps	717 Mbps
VPNGW2	1400 Mbps	1430 Mbps
VPNGW3	1810 Mbps	2880 Mbps

For comparison here are the results form the now depreciated gateway types Standard and High Performance:

Gateway Type	Single Stream Throughput	‘N’ Streams Throughput (1x #Cores)
Standard	472Mbps	580 Mbps
High Performance	720 Mbps	980 Mbps

Peered VNets via two BGP Gateways one in each region

Gateway Type	Single Stream Throughput	‘N’ Streams Throughput
VPNGW1	550 Mbps	670 Mbps
VPNGW2	650 Mbps	780 Mbps
VPNGW3	650 Mbps	650 Mbps

For comparison here are the results form the now depreciated gateway types Standard and High Performance:

Gateway Type	Single Stream Throughput	‘N’ Streams Throughput
Standard	200 Mbps	280 Mbps
High Performance	210 Mbps	411 Mbps