JS setInterval() mem leak

Question

I know it's bunch of questions and answers here about this problem, but I don't know if it's realy applies to mine case.

I have a time script, with setInterval function. It works fine, for first minutes, but then in chrome/opera task manager I see that tab with this script running going from 40mb to 2-3gb! It's insane, and I don't know how to fix that. Only if rewrite all script in a different way.

Script:

function checkTime(i) {
 return (i < 10) ? "0" + i : i;
};
function calcTime(city, offset) {
 d = new Date();
 utc = d.getTime() + (d.getTimezoneOffset() * 60000);
 nd = new Date(utc + (3600000*offset)),
 h = checkTime(nd.getHours()),
 m = checkTime(nd.getMinutes()),
 s = checkTime(nd.getSeconds());
 return nd.toLocaleString();
};
function updateTime() {
 if (document.getElementById('timeMoscow')) {
 calcTime('Moscow', '+3');
 document.getElementById('timeMoscow').innerHTML = h + ":" + m /*+ ":" + s*/;
 }
 if (document.getElementById('timeKiev')) {
 calcTime('Kiev', '+2');
 document.getElementById('timeKiev').innerHTML = h + ":" + m /*+ ":" + s*/;
 } else 
 if (document.getElementById('timeAstana')) {
 calcTime('Astana', '+6');
 document.getElementById('timeAstana').innerHTML = h + ":" + m /*+ ":" + s*/;
 }
 if (document.getElementById('timeNewYork')) {
 calcTime('NewYork', '-4');
 document.getElementById('timeNewYork').innerHTML = h + ":" + m /*+ ":" + s*/;
 }
 setInterval(updateTime, 500); //Problem
}
updateTime();

• abhishekkannojia: I see stackoverflow :)
• JJJ: setInterval repeats automatically, you don't have to re-call it. You're confusing it with setTimeout.
• abhishekkannojia: Well you are recursively setting up interval which in turn calls updateTime which again sets up Interval to call updateTime and this happens again and again until you run out of memory

Answer 1

You are recursively invoking updateTime function that using setInterval which is repeatedly calls updateTime. Remove setInterval() call from the method and invoke it like.

function updateTime() {
 //You rest of code
}
setInterval(updateTime, 500);