diff --git a/doc/api/timers.markdown b/doc/api/timers.markdown index ee1e5ffaa1..8395ac6779 100644 --- a/doc/api/timers.markdown +++ b/doc/api/timers.markdown @@ -54,11 +54,10 @@ callbacks and before `setTimeout` and `setInterval` . Returns an `immediateId` for possible use with `clearImmediate()`. Optionally you can also pass arguments to the callback. -Immediates are queued in the order created, and are popped off the queue once -per loop iteration. `setImmediate` will yield to the event loop after firing a -queued callback to make sure I/O is not being starved. While order is preserved -for execution, other I/O events may fire between any two scheduled immediate -callbacks. +Callbacks for immediates are queued in the order in which they were created. +The entire callback queue is processed every event loop iteration. If you queue +an immediate from a inside an executing callback that immediate won't fire +until the next event loop iteration. ## clearImmediate(immediateId) diff --git a/test/simple/test-timers-immediate-queue.js b/test/simple/test-timers-immediate-queue.js new file mode 100644 index 0000000000..cce43a1aca --- /dev/null +++ b/test/simple/test-timers-immediate-queue.js @@ -0,0 +1,55 @@ +// Copyright Joyent, Inc. and other Node contributors. +// +// Permission is hereby granted, free of charge, to any person obtaining a +// copy of this software and associated documentation files (the +// "Software"), to deal in the Software without restriction, including +// without limitation the rights to use, copy, modify, merge, publish, +// distribute, sublicense, and/or sell copies of the Software, and to permit +// persons to whom the Software is furnished to do so, subject to the +// following conditions: +// +// The above copyright notice and this permission notice shall be included +// in all copies or substantial portions of the Software. +// +// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS +// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF +// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN +// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, +// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR +// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE +// USE OR OTHER DEALINGS IN THE SOFTWARE. + +var common = require('../common'); +var assert = require('assert'); + +// setImmediate should run clear its queued cbs once per event loop turn +// but immediates queued while processing the current queue should happen +// on the next turn of the event loop. + +// in v0.10 hit should be 1, because we only process one cb per turn +// in v0.11 and beyond it should be the exact same size of QUEUE +// if we're letting things recursively add to the immediate QUEUE hit will be +// > QUEUE + +var ticked = false; + +var hit = 0; +var QUEUE = 1000; + +function run() { + if (hit === 0) + process.nextTick(function() { ticked = true; }); + + if (ticked) return; + + hit += 1; + setImmediate(run); +} + +for (var i = 0; i < QUEUE; i++) + setImmediate(run); + +process.on('exit', function() { + console.log('hit', hit); + assert.strictEqual(hit, QUEUE, 'We ticked between the immediate queue'); +});