var LRU = require('lru-cache'); var max = +process.argv[2] || 10240; var more = 102400; var cache = LRU({ max: max, maxAge: 86400e3 }); // fill cache for (var i = 0; i < max; ++i) { cache.set(i, {}); } var start = process.hrtime(); // adding more items for ( ; i < max+more; ++i) { cache.set(i, {}); } var end = process.hrtime(start); var msecs = end[0] * 1E3 + end[1] / 1E6; console.log('adding %d items took %d ms', more, msecs.toPrecision(5));