Loon4Mac Build 1007 improves TCP forwarding performance. On an Apple M1 Max, a single upload stream reached 12.25 Gbps, a single download stream reached 13.97 Gbps, and four download streams reached a combined 20.61 Gbps.
Results
Test environment
| Item | Configuration |
|---|---|
| Device | Apple M1 Max with 32 GB of memory |
| System | macOS 27.2 |
| Loon | Loon4Mac Build 1007 |
| Test tool | Apple iperf3-darwin 3.8.1 |
| TUN MTU | 4000 |
Test traffic originated on the Mac and passed through Loon's TUN and TCP stack to a local iperf3 server. Each test used a 2-second warm-up and a 10-second measurement period and was run once.
| Test | TCP throughput | Peak Loon NE RSS |
|---|---|---|
| Single-stream upload | 12.25 Gbps | 55.70 MiB |
| Single-stream download | 13.97 Gbps | 59.28 MiB |
| Four-stream upload (combined) | 10.67 Gbps | 60.55 MiB |
| Four-stream download (combined) | 20.61 Gbps | 90.23 MiB |
Before testing, Loon NE used approximately 46.45 MiB of RSS while idle. The four-stream values are the combined throughput of four TCP connections. RSS is the memory used by the entire Loon network extension process, not by a single connection.
Test procedure
Loon configuration
Merge the following entries into the current configuration. Place the DOMAIN rule before FINAL:
[Host]
bench.loon.test = 127.0.0.1
[Rule]
DOMAIN,bench.loon.test,DIRECT
Save the configuration and connect Loon. Do not add bench.loon.test to real-ip or the system /etc/hosts file.
Automated test script
Download the Loon4Mac TCP test script
Run it after downloading:
/bin/bash ~/Downloads/loon4mac-tcp-test.sh
The script tests single-stream upload, single-stream download, four-stream upload, and four-stream download in sequence, records Loon NE RSS, and saves the results in the current directory.
Manual testing
Start the server in one Terminal window:
/usr/bin/arch -arm64 /usr/bin/iperf3-darwin -s -B 127.0.0.1 -p 5201
Run the following commands in another Terminal window:
# Single-stream upload
/usr/bin/arch -arm64 /usr/bin/iperf3-darwin -c bench.loon.test -4 -p 5201 -O 2 -t 10 -i 1
# Single-stream download
/usr/bin/arch -arm64 /usr/bin/iperf3-darwin -c bench.loon.test -4 -p 5201 -O 2 -t 10 -i 1 -R
# Four-stream upload
/usr/bin/arch -arm64 /usr/bin/iperf3-darwin -c bench.loon.test -4 -p 5201 -O 2 -t 10 -i 1 -P 4
# Four-stream download
/usr/bin/arch -arm64 /usr/bin/iperf3-darwin -c bench.loon.test -4 -p 5201 -O 2 -t 10 -i 1 -P 4 -R
For single-stream tests, use the final receiver result. For four-stream tests, use [SUM] receiver. The client must connect to bench.loon.test; traffic sent directly to 127.0.0.1 does not pass through Loon.