The document discusses Docker network performance testing in public clouds. It compares the performance of different Docker networking solutions (Flannel, Weave, Project Calico) to native networking performance on AWS and Azure VMs. The results show that while some Docker networks have little performance overhead, others like Weave can reduce bandwidth significantly compared to native networking. The document recommends further testing Docker network performance with real applications.

1. Docker network performance in
the public cloud
Arjan Schaaf - Luminis Technologies
container.camp London
September 11th 2015

2. Cloud RTI
• Luminis Technologies
• Founded in The Netherlands
• amdatu.com PAAS
• both public and private clouds
• cloud provider independent

3. Cloud RTI
• CoreOS
• Docker
• Kubernetes
• Load balancing, Data Stores, ELK
• High available, scalable applications with centralised
logging, monitoring and metrics

4. Choose your cloud wisely
• comparing cloud VM’s based on price or hardware
specification isn’t enough
• cloud providers throttle their VM’s differently
• don’t trust specifications on ‘paper’

5. Azure vs AWS
AZURE AWS
INSTANCE TYPE PRICE NETWORK INSTANCE TYPE PRICE NETWORK
A0 $0,018 5 Mbps t2.micro $0,014 Low to Moderate
A1 $0,051 100 Mbps t2.medium $0,056 Low to Moderate
D1 $0,084 unknown m4.large $0,139 Moderate
D2 $0,168 unknown m4.xlarge $0,278 High
A8 $1,97 40Gbit/s InfiniBand m4.10xlarge $2,78 10 Gbit

6. Native Network Test Setup
• qperf: short running test
• iperf3: longer running test using parallel connections

7. qperf server container
docker run -dti -p 4000:4000 -p 4001:4001 arjanschaaf/centos-qperf -lp 4000

8. qperf client container
docker run -ti --rm arjanschaaf/centos-qperf <ip address> -lp 4000 -ip 4001 tcp_bw tcp_lat

9. iperf3 server container
docker run -dti -p 5201:5201 arjanschaaf/centos-iperf3--server

10. iperf3 client container
docker run -ti --rm arjanschaaf/centos-iperf3 -c <ip address> -t 300 -P 128

11. Native Network Test Results
Bandwidth
0
350
700
1050
1400
A0 A1 D1 D2 A8 t2.micro t2.medium m4.large m4.xlarge m4.10xlarge
qperf iperf3

12. Native Network Test Results
Bandwidth
0
125
250
375
500
A0 A1 D1 D2 A8 t2.micro t2.medium m4.large m4.xlarge
qperf iperf3

13. Native Network Test Results
qperf latency
0
125
250
375
500
A0 A1 D1 D2 A8 t2.micro t2.medium m4.large m4.xlarge m4.10xlarge

14. Docker Networking
• Connect containers over the host interface (use
ambassadors!)
• Use a SDN to connect your Docker cluster nodes
• weave
• flannel
• Project Calico

15. Before Docker 1.7
• Approach depended on the SDN
• replace the docker bridge
• proxy in front on docker daemon

16. Docker libnetwork
• Announced along with Docker 1.7 as an experimental
feature
• Networking Plugins: batteries included but swappable
• Included batteries are based on Socketplane
• Other plugins announced by: Weave, Project Calico,
Cisco, VMware and others

17. Choose your SDN wisely
• Functional features like encryption & DNS
• Support for libnetwork, kubernetes etc etc
• Implementations can be fundamentally different
• overlay networks like Flannel & Weave
• different overlay backend implementations (for example
UDP)
• L2/L3 based networks like Project Calico

18. Flannel
• Created by CoreOS
• Easy to setup
• Different backends
• UDP
• VXLAN
• AWS VPC (uses VPC routing table)
• GCE (uses Network routing table)

19. Weave
• Used Weave 1.0.3, 1.1 released this week
• DNS
• Proxy based approach
• Different backends
• pcap (default)
• VXLAN (fast-datapath-preview)

20. Project Calico
• Uses vRouters connected over BGP routes
• No additional overlay when running on a L2 or L3
network (think datacentre!)
• Won’t run on public clouds like AWS without a IPIP
tunnel
• Extensive and simple network policies (tenant isolation!)
• Very promising integration with Kubernetes

21. Docker Network Test Setup
• exactly the same as the “native” test but this time: use
the IP-address or DNS name of the container!

22. Docker Network Test Results
qperf bandwidth
0
350
700
1050
1400
t2.micro t2.medium m4.large m4.xlarge m4.10xlarge
native flannel UDP flannel vxlan weave pcap calico

23. Docker Network Test Results
qperf bandwidth
0
75
150
225
300
t2.micro t2.medium m4.large m4.xlarge
native flannel UDP flannel vxlan weave pcap calico

24. Docker Network Test Results
iperf3 bandwidth
0
300
600
900
1200
t2.micro t2.medium m4.large m4.xlarge m4.10xlarge
native flannel UDP flannel vxlan weave pcap calico

25. Docker Network Test Results
iperf3 bandwidth
0
25
50
75
100
t2.micro t2.medium m4.large m4.xlarge
native flannel UDP flannel vxlan weave pcap calico

26. Docker Network Test Results
qperf latency
0
100
200
300
400
t2.micro t2.medium m4.large m4.xlarge m4.10xlarge
native flannel UDP flannel vxlan weave pcap calico

27. Native vs SDN performance
INSTANCE TYPE FLANNEL UDP FLANNEL VXLAN WEAVE PCAP CALICO
IPERF IPERF IPERF IPERF
T2.MICRO -16% -2% -14% -14%
T2.MEDIUM -1% -1% -3% -3%
M4.LARGE -1% -1% -1% -1%
M4.XLARGE -0% -1% -1% -1%
M4.10XLARGE -55% -20% -79% -32%

28. Native vs SDN performance
& cpu load client + server
INSTANCE TYPE FLANNEL UDP FLANNEL VXLAN WEAVE PCAP CALICO
IPERF C S IPERF C S IPERF C S IPERF C S
T2.MICRO -16% 62,7% 29% -2% 11,7% 23,2% -14% 59,7% 89,5% -14% 26% 57%
T2.MEDIUM -1% 28,7% 20,2% -1% 20,6% 18,7% -3% 52,6% 33,1% -3% 17% 37%
M4.LARGE -1% 15,4% 12,7% -1% 10% 10% -1% 34,1% 24,8% -1% 21% 21%
M4.XLARGE -0% 9,4% 7,9% -1% 6,6% 7,3% -1% 22,9% 18,9% -1% 12% 10%
M4.10XLARGE -55% 2,8% 5,0% -20% 2,7% 3,4% -79% 14,8% 13,5% -32% 3% 4%

29. cpu load compared to native
test results
INSTANCE TYPE FLANNEL UDP FLANNEL VXLAN WEAVE PCAP CALICO
C S C S C S C S
T2.MEDIUM 95% 57% 40% 45% 258% 157% 15% 184%
M4.LARGE 108% 46% 35% 15% 361% 185% 177% 140%
M4.XLARGE 92% 44% 35% 33% 367% 244% 141% 82%

30. Conclusion
• Happy with choice for Flannel VXLAN
• Interested in Project Calico in combination with
Kubernetes

31. Conclusion
• synthetic tests are a great starting point
• don’t forget to validate the results with “real life” load
tests on your application(s)

32. Links
• http://weave.works
• http://blog.weave.works/2015/06/12/weave-fast-
datapath
• http://coreos.com/flannel
• http://www.projectcalico.org
• http://linux.die.net/man/1/qperf
• http://github.com/esnet/iperf

33. @arjanschaaf
arjanschaaf.github.io
www.luminis.eu