The v8.setFlagsFromString() method can be used to programmatically set V8 command-line flags. This method should be used with care. Changing settings after the VM has started may result in unpredictable behavior, including crashes and data loss; or it may simply do nothing.

The V8 options available for a version of Node.js may be determined by running node --v8-options.

Usage:

// Print GC events to stdout for one minute.
import v8 from 'node:v8';
v8.setFlagsFromString('--trace_gc');
setTimeout(() => { v8.setFlagsFromString('--notrace_gc'); }, 60e3);