vpncloud/performance.md

Performance Tests

Test setup

Sender node:

• Intel(R) Core(TM) i5-2540M CPU @ 2.60GHz
• 8 GiB Ram
• Intel 82579LM Gigabit Network
• Ubuntu 14.04 (Kernel 3.13.0-65-generic)

Receiver node:

• Intel(R) Core(TM) i5-3450 CPU @ 3.10GHz
• 16 GiB Ram
• Realtek RTL8111/8168/8411 Gigabit Network
• Ubuntu 14.04 (Kernel 3.13.0-63-generic)

VpnCloud version: VpnCloud v0.3.1, protocol version 1, libsodium 1.0.7 (AES256: true)

The sender runs the following command:

$> ./vpncloud -t tap -l SENDER:3210 -c RECEIVER:3210 \
   --ifup 'ifconfig $IFNAME 10.2.1.1/24 mtu 1400 up' &

and the receiver runs:

$> ./vpncloud -t tap -l RECEIVER:3210 -c SENDER:3210 \
   --ifup 'ifconfig $IFNAME 10.2.1.2/24 mtu 1400 up' &
$> iperf -s &
$> top

For encrypted tests, --shared-key test --crypto METHOD is appended.

Throughput

The throughput is measured with the following command:

$> iperf -c DST -t 60

The test is run in 3 steps:

• Native throughput without VpnCloud (DST is the native address of the receiver)
• Throughput via VpnCloud (DST is 10.2.1.2)
• Encrypted throughput via VpnCloud (DST is 10.2.1.2)

Throughput test	Bandwidth	CPU usage (one core)
Without VpnCloud	920 Mbits/sec	-
Unencrypted VpnCloud	883 Mbits/sec	80% / 75%
Encrypted VpnCloud (ChaCha20)	814 Mbits/sec	90% / 90%
Encrypted VpnCloud (AES256)	821 Mbits/sec	85% / 85%

Latency

The latency is measured with the following command:

$> ping DST -c 100000 -i 0.001 -s SIZE -U -q

For all the test, the best average RTT out of 3 runs is selected. The latency is assumed to be half of the RTT.

Payload size	100 bytes	500 bytes	1000 bytes
Without VpnCloud	156 µs	164 µs	171 µs
Unencrypted VpnCloud	205 µs (+50 µs)	220 µs (+61 µs)	236 µs (+65 µs)
Encrypted VpnCloud (ChaCha20)	222 µs (+17 µs)	242 µs (+22 µs)	258 µs (+22 µs)
Encrypted VpnCloud (AES256)	216 µs (+15 µs)	232 µs (+12 µs)	250 µs (+14 µs)

Conclusion

• VpnCloud achieves over 850 MBit/s with default MTU settings.
• In encrypted mode, VpnCloud reaches over 800 MBit/s with default MTU settings.
• VpnCloud adds about 70µs to the latency.
• Encryption adds an additional latency up to 20µs.