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mqtt-backend/node_modules/retimer/README.md

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+# retimer  [![Build Status](https://travis-ci.org/mcollina/retimer.png)](https://travis-ci.org/mcollina/retimer)
+
+reschedulable setTimeout for your node needs. This library is built for
+building a keep alive functionality across a large numbers of
+clients/sockets.
+
+Rescheduling a 10000 functions 20 times with an interval of 50ms (see
+`bench.js`), with 100 repetitions:
+
+* `benchSetTimeout*100: 40.295s`
+* `benchRetimer*100: 36.122s`
+
+
+## Install
+
+```
+npm install retimer --save
+```
+
+## Example
+
+```js
+var retimer = require('retimer')
+var timer = retimer(function () {
+  throw new Error('this should never get called!')
+}, 20)
+
+setTimeout(function () {
+  timer.reschedule(50)
+  setTimeout(function () {
+    timer.clear()
+  }, 10)
+}, 10)
+```
+
+## API
+
+### retimer(callback, timeout, [...args])
+
+Exactly like your beloved `setTimeout`.
+Returns a `Retimer object`
+
+### timer.reschedule(timeout)
+
+Reschedule the timer.
+Retimer will not gove any performance benefit if the specified timeout comes __before__ the original timeout.
+
+### timer.clear()
+
+Clear the timer, like your beloved `clearTimeout`.
+
+## How it works
+
+Timers are stored in a Linked List in node.js, if you create a lot of
+timers this Linked List becomes massive which makes __removing a timer an expensive operation__.
+Retimer let the old timer run at its time, and schedule a new one accordingly, when the new one is __after__ the original timeout.
+There is no performance gain when the new timeout is before the original one as retimer will just __remove the previous timer__.
+
+## License
+
+MIT