Running AceBase server in a cluster

[appy-one]

Clustering info

I created this discussion to provide updates about how to run an AceBase server in a pm2, cloud or standard Node.js cluster.

Cloud based (multiple machine) clusters

If you want to run an AceBase server in a cloud-based cluster, where multiple machines are accessing the same data files, you have to use an external IPC server: https://github.com/appy-one/acebase-ipc-server

pm2 / Node.js clusters

If you want to use pm2 to vertically scale the processes running on a single machine, or want to be able to access the same database files from multiple isolated processed, enable the new socket IPC mode (requires acebase-server v1.18.0+). This will automatically spawn a single master process for the database (if it's not running yet), and connects to it using a Unix socket or Windows named pipe.
Simply pass ipc: 'socket' in your config to enable this and it'll work!

const server = new AceBaseServer('mydb', { host: 'localhost', port: 3000, ipc: 'socket' });

That's it!

Manual Node.js cluster plumbing

Before the socket IPC mode was introduced, you had to (and still can) use the manual IPC configuration using master and worker roles. It's best not to use this approach anymore, but I'll include put the example code taken from cluster.ts here for future reference:

import { AceBase } from 'acebase';
import { AceBaseServer, AceBaseServerSettings } from 'acebase-server';
import * as cluster from 'cluster';
import * as os from 'os';
const numCPUs = os.cpus().length;

const dbname = 'default';
const options: AceBaseServerSettings = { /* default options */ };
options.authentication = { enabled: false };
options.https = { enabled: false };

if (cluster.isMaster) {
    // Startup master
    console.log(`Starting database server cluster with ${numCPUs} workers`);
    const master = new AceBase(dbname, options);
    master.once('ready', () => {
        console.log(`Master database server started on process ${process.pid}`);
    });

    for (let i = 0; i < numCPUs; i++) {
        const worker = cluster.fork();
    }

    cluster.on('exit', (worker, code, signal) => {
        console.error(`worker ${worker.process.pid} died`);
        cluster.fork(); // restart
    });
}
else {
    console.log(`Worker ${process.pid} is running`);

    const server = new AceBaseServer(dbname, options);
    server.ready(() => {
        console.log(`Worker database server started on process ${process.pid}`);
    });
}