pocket-autonice

pocket-autonice

When running a pocket node and blockchain cluster, it is advantageous to the node runner and good for the network overall that the cluster perform to its maximum capability. This project helps achieve that aim by boosting the priority of the pocket and the relay chain processes when relays are being served.

Requirements

Pocket-autonice uses the Linux renice command to boost the processes of the user under which the pocket and relay chain processes are running. Why not use the specific pids of the pocket and relay chian processes? That would require reconfiguring pocket-autonice everytime a process was restarted and receives a new pid.

So that means that the pocket and relay chain processes must each be running under a different Linux user. For services running under systemd, the user can be set with

[Service]
User=<username>
Group=<groupname>
ExecStart=...

For services running in docker, start the docker container with the --user argument specifying the user it should run under.

Installation

Start with just a few servers in your cluster to get the hang of this. Maybe even start locally on your pocket node. Eventually you will want to install pocket-autonice on all your servers and configure it to coordinate process boosting across your cluster.

Dependencies:

• Install zeromq dependencies from the system package manager. For example on Ubuntu 20.04:

apt install -y libtool pkg-config gcc g++ make libsodium-dev libczmq-dev

• Install Go 1.17+. Ensure that the go executables as well as $GOPATH/bin are in your $PATH.

• Install pocket-autonice:

go install github.com/blocktop/pocket-autonice@latest

How to boost your pocket and relay chain performance

Follow the steps below carefully.

Chains configuration

As root, dump the config_example.yaml file by running:

pocket-autonice dump-config

The file will be saved in the $HOME/.pocket-autonice directory. Rename this file to config.yaml in the same directory.

On each server, set the relay chains that are active on that server. This should be a map of relay chain ID to the Linux user running that relay chain process. You should also include pocket-core in this configuration on the server running pocket-core.

chains:
  "0001": pocket
  "0009": polygon
  "0021": geth

Networking configuration

TL;DR:

On pocket node:

subscriber_address: 10.0.0.2:5555
publish_to_endpoints:
  - 10.0.0.2:5555
  - 10.0.0.3:5555
  - all servers... 

On servers with relay chains only:

subscriber_address: 10.0.0.3:5555

Any open port can be used. For a single server setup, replace the IP address with 127.0.0.1.

Open the firewall as needed to support both UDP and TCP on the chosen port(s).

Details

Pocket-autonice works by looking for changes in the relay counts in the prometheus output of the pocket-core process. When a change is detected, a message is published on a pub-sub channel containing the chain ID that is currently being served. All servers in the cluster (including the pocket node) will receive that message and adjust the priority of that relay chain if it is configured (see above). In addition, a message of 0001 is published when any relay chain is being served to tell pocket-core to boost itself.

The server running pocket-core is the "poller", meaning it polls prometheus output. In order for publushed messages to reach all servers, their subscriber addresses must be listed in the config item publish_to_endpoints:

publish_to_endpoints:
  - 10.0.0.2:5555
  - 10.0.0.3:5555
  - etc.. 

On all servers (including the pocket node), the subscriber_address configuration must be provided in order for that server to receive messages and for pocket-autonice to boost pocket or relay chain processes.

subscriber_address: 10.0.0.2:5555

That's it. All other configuration values would only need to be changed for an unusual setup. See the documentation in the config_example.yaml file for information on all configuration options.

Running pocket-autonice

Try running with the --dry-run flag for a few relay sessions until you get the hang of what pocket-autonice will be doing to your processes.

Pocket-autonice must be run as root or under a process that has passwordless sudo. This is because the renice command is a privileged command. If using sudo set the run_with_sudo config value.

On the server running pocket-core:

pocket-autonice --with-poller

On all other servers:

pocket-autonice

Running pocket-autonice with systemd

To run pocket-autonice automatically upon server startup add a pocket-autonice.service to systemd.

Save the following as /etc/systemd/system/pocket-autonice.service:

[Unit]
Description=Pocket Autonice
After=network.target

[Service]
ExecStart=<full path to pocket-autonice>
Restart=on-failure
KillSignal=SIGTERM
TimeoutStopSec=30

[Install]
WantedBy=default.target

Testing

On a macOS device, install the ZeroMQ libraries.

brew install libsodium zeromq czmq

Ensure that Go has the ability to compile C modules.

go env CGO_ENABLED
-> 1