chpr-blocked

chpr-blocked is a tiny utility to monitor event loop blocking, inspired from tj/blocked, but configurable with environment variables.

When the event loop is blocked for more than a set threshold (defaults to 100ms), an error log is emitted, using chpr-logger.

There is a "warmup delay" (defaults to 2000ms), because it's ok to use a lot of CPU in at the statup of the node app (e.g. to require most of the app code).

Installation

Install the package.

npm i chpr-blocked --save

Then require the module in the entry point in your code (e.g. server.js, worker.js, etc...).

require('chrp-blocked');

The "warmup delay" starts immediately.

If you want to prevent this from happening, you can do const blocked = require('chrp-blocked').stop(); and use blocked.BlockedMonitor directly.

Configuration

The configuration is done with environment variables.

Name	Description	Default
BLOCKED_DELAY	The tolerated warmup time after requiring chpr-blocked, milliseconds	2000
BLOCKED_THERSHOLD	The threshold above which an error will be logged, once the warmup delay is over	100