trakx

README

Trakx

Performance focused BitTorrent tracker supporting HTTP and UDP + IPv4 and IPv6.

• Trakx
  • ❤️‍🔥 Instances
  • 🚀 Install
  • 🔧 Configuration
    • Configuration file
    • Default configuration & webserver files
    • Binding to privileged ports
    • Netdata setup
    • Build Tags
  • 📈 Performance

❤️‍🔥 Instances

Try Trakx for yourself! These instances are hosted on Oracles always free tier.

Status	Protocol	Address
✅Ok	IPv4 UDP	udp://u4.trakx.crim.ist:1337
✅Ok	IPv6 UDP	udp://u6.trakx.crim.ist:1337
❌Deprecated	IPv4 HTTP	http://h4.trakx.crim.ist/announce
❌Deprecated	IPv6 HTTP	http://h6.trakx.crim.ist/announce

🚀 Install

Go 1.19+ required.

git clone https://github.com/crimist/trakx && cd trakx

# install to go bin
go install .
trakx status # generates configuration

# or build
go build .
./trakx status # generates configuration

See configuration and netdata setup.

🔧 Configuration

Configuration file

The configuration file can be found at ~/.config/trakx/trakx.yaml. You'll have to run the trakx controller at least once to generate this file.

Config settings can be overwritten with environment variables:

$ cat trakx.yaml
...
loglevel = error
...

$ TRAKX_LOGLEVEL=DEBUG trakx run
2022-01-16T19:52:25.627-0800    DEBUG   Debug level enabled, debug panics are on
...

Trakx attempts to load the config file from the following directories in order:

• .
• ~/.config/trakx/

Default configuration & webserver files

You can modify the default configuration and files served by the webserver in the tracker/config/embeded/ folder.

NOTE: Trakx webserver will only serve files at their full path. dmca will 404, dmca.html will 200.

Binding to privileged ports

To bind to privileged ports I recommend using CAP_NET_BIND_SERVICE. More information can be found here.

$ sudo setcap 'cap_net_bind_service=+ep' ./trakx
$ TRAKX_TRACKER_HTTP_PORT=80 ./trakx run
2022-04-05T16:18:05.847-0700    INFO    HTTP tracker enabled    {"port": 80}

Netdata setup

Warning: install.sh will overwrite go_expvar.conf. If you are using other expvar programs with netdata manually merge the two files.

• Run /etc/netdata/edit-config python.d.conf, change go_expvar to yes.
• Customize the url in netdata/expvar.conf if needed.
• Install netdata plugins with cd netdata; ./install.sh.

Build Tags

You can build with different tags with go build/install -tags <tag> .

Tags

• fast will build without IP, seed, and leech metrics which will reduce cpu and memory usage
• heroku will build trakx for app engines. This means the controller will not be built and trakx will run immediately when the binary is executed.

📈 Performance

The following metrics were collected on Heroku free tier running an HTTP tracker with the fast tag disabled.

Heroku dashboard:

Database stats:

Flamegraph:

Trakx has been optimized to use a little CPU time as possible. In most cases, almost all CPU time will be spent handing (negotiating/send/recv) connections, especially for TCP (HTTP).

Trakx has also been optimized to use minimal memory and is mostly limited by the go GC. In this example the GC runs every 2 minutes (the forced GC period) at this level of traffic. The inuse_space delta from GC is 7.5% meaning this collection frequency would be sustained at GOGC=8.