var toobusy = require('toobusy-js'); // Set maximum lag to an aggressive value. toobusy.maxLag(10); // Set check interval to a faster value. This will catch more latency spikes // but may cause the check to be too sensitive. toobusy.interval(250); // Set smoothing factor on rise to a lower value. This will make it less sensible // to spikes. Default is 1/3. toobusy.smoothingFactorOnRise(1/4); // Set smoothing factor on fall to a higher value. This will make it recover faster // after spikes. Default is 2/3. toobusy.smoothingFactorOnFall(3/4); // You can overwrite this function to change the way currentLag is calculated. // This is the default implementation. toobusy.lagFunction = function(lag, currentLag, smoothingUp, smoothingDown) { var factor = lag > currentLag ? smoothingUp : smoothingDown; return factor * lag + (1 - factor) * currentLag; } // Get current maxLag or interval setting by calling without parameters. var currentMaxLag = toobusy.maxLag(), interval = toobusy.interval(); toobusy.onLag(function(currentLag) { console.log("Event loop lag detected! Latency: " + currentLag + "ms"); }); // check if node is too busy if (toobusy()) { console.warn("TooBusy!"); } console.log("Current adjusted event lag", toobusy.lag(), "ms");