Is using setInterval ok in Node apps?

[Wes Gamble]

All,

I am a noob to Node.

I noticed a pattern in the app that I'm working on (inherited) where the first invocation of a function happens through setTimeout (e.g setTimeout(x, 5000) and then the (invoked) function itself does whatever and then calls setTimeout on itself again (setTimeout(x, 5000).

I decided to replace this with one call to setInterval on the function like so: setInterval(x, 5000). But I don't see it getting re-executed. I did some Googling and I can't find anything that says not to use setInterval.

Is it ok to use setInterval inside of a Node app?

Thanks,
Wes

[Jann Horn]

2011/9/24 Wes Gamble <we...@att.net>:

> Is it ok to use setInterval inside of a Node app?

Yes.

$ node
> setInterval(function(){console.log("pong")},1000)
{ repeat: 1, callback: [Function] }
> pong
pong
pong
pong
pong
pong

[Branko Vukelić]

On 2011-09-23 17:27 -0500, Wes Gamble wrote:
> SNIPPAGE

>
> I decided to replace this with one call to setInterval on the function like so:

That's not quite the same thing, though. If you do a setTimeout, and
call another setTimeout from within the callback, you have to account
for the time it takes to execute the code up to the second invocation of
setTimeout. e.g.:

function func() {
// Simulating code that takes 200ms to execute:
setTimeout(function() {
console.log('Done');
setTimeout(func, 5000);
}, 200);
}

setTimeout(func, 5000);

This code is executed approximately every 5200ms after the first 5000ms
(unless I have a bug in there), because whatever the callback itself
takes 200ms to execute. Of course, you can imagine what happens if the
200ms is some random time frame.

> setInterval(x, 5000). But I don't see it getting re-executed. I did some
> Googling and I can't find anything that says not to use setInterval.

I don't see why x would not execute repeatedly unless x has a bug in it.
In the app I'm working on, I actually use it to start a background
process that keeps on troughout the uptime of the app.

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[Wesley Gamble]

My error was pretty simple - I forgot to put the function call inside of an anonymous function since I was passing a parameter to it.

Thx for the help.

W

Sent from my iPhone

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[Sarfaraz Farooqui]

I am using setInterval @ 1/10th of a second to broadcast Stock Data to all connected Clients.

 

 

 

[Egor Egorov]

No HFT trading, huh? :)