| 'use strict'; |
| require('../common'); |
| const assert = require('assert'); |
| |
| const start = process.cpuUsage(); |
| |
| // Run a busy-loop for specified # of milliseconds. |
| const RUN_FOR_MS = 500; |
| |
| // Define slop factor for checking maximum expected diff values. |
| const SLOP_FACTOR = 2; |
| |
| // Run a busy loop. |
| const now = Date.now(); |
| while (Date.now() - now < RUN_FOR_MS); |
| |
| // Get a diff reading from when we started. |
| const diff = process.cpuUsage(start); |
| |
| const MICROSECONDS_PER_MILLISECOND = 1000; |
| |
| // Diff usages should be >= 0, <= ~RUN_FOR_MS millis. |
| // Let's be generous with the slop factor, defined above, in case other things |
| // are happening on this CPU. The <= check may be invalid if the node process |
| // is making use of multiple CPUs, in which case, just remove it. |
| assert(diff.user >= 0); |
| assert(diff.user <= SLOP_FACTOR * RUN_FOR_MS * MICROSECONDS_PER_MILLISECOND); |
| |
| assert(diff.system >= 0); |
| assert(diff.system <= SLOP_FACTOR * RUN_FOR_MS * MICROSECONDS_PER_MILLISECOND); |