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1-js/06-advanced-functions/08-settimeout-setinterval/article.md
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@ -158,7 +158,7 @@ The `setTimeout` above schedules next call right at the end of the current one `
Recursive `setTimeout` is more flexible method than `setInterval`. This way the next call may be scheduled differently, depending on the results of the current one. Recursive `setTimeout` is more flexible method than `setInterval`. This way the next call may be scheduled differently, depending on the results of the current one.
For instance, we need to write a service that each 5 seconds sends a request to server asking for data, but in case the server is overloaded, it should increase the interval to 10, 20, 40 seconds... For instance, we need to write a service that every 5 seconds sends a request to server asking for data, but in case the server is overloaded, it should increase the interval to 10, 20, 40 seconds...
Here's the pseudocode: Here's the pseudocode:
```js ```js
@ -178,7 +178,7 @@ let timerId = setTimeout(function request() {
``` ```
And if we regulary have CPU-hungry tasks, then we can measure the time taken by the execution and plan the next call sooner or later. And if we regularly have CPU-hungry tasks, then we can measure the time taken by the execution and plan the next call sooner or later.
**Recursive `setTimeout` guarantees a delay between the executions, `setInterval` -- does not.** **Recursive `setTimeout` guarantees a delay between the executions, `setInterval` -- does not.**
@ -209,7 +209,7 @@ Did you notice?...
**The real delay between `func` calls for `setInterval` is less than in the code!** **The real delay between `func` calls for `setInterval` is less than in the code!**
That's natural, because the time taken by `func` execution "consumes" a part of the interval. That's natural, because the time is taken by `func` execution "consumes" a part of the interval.
It is possible that `func` execution turns out to be longer than we expected and takes more than 100ms. It is possible that `func` execution turns out to be longer than we expected and takes more than 100ms.
@ -260,7 +260,7 @@ The first line "puts the call into calendar after 0ms". But the scheduler will o
There's a trick to split CPU-hungry task using `setTimeout`. There's a trick to split CPU-hungry task using `setTimeout`.
For instance, syntax highlighting script (used to colorize code examples on this page) is quite CPU-heavy. To hightlight the code, it performs the analysis, creates many colored elements, adds them to the document -- for a big text that takes a lot. It may even cause the browser to "hang", that's unacceptable. For instance, syntax highlighting script (used to colorize code examples on this page) is quite CPU-heavy. To highlight the code, it performs the analysis, creates many colored elements, adds them to the document -- for a big text that takes a lot. It may even cause the browser to "hang", that's unacceptable.
So we can split the long text to pieces. First 100 lines, then plan another 100 lines using `setTimeout(...,0)`, and so on. So we can split the long text to pieces. First 100 lines, then plan another 100 lines using `setTimeout(...,0)`, and so on.