setTimeout calls function repeatedly and causes page to hang - spring-mvc

Question

I have three javascript functions defined that creates ajax calls to my java controller. I set timeouts for two of the functions to update the ping status every 3 seconds and to update performance status every 5 min. The ping update every 3 seconds seems to be working correctly but when the updatePerformance method gets called my controller method gets executed 5 or so times in a row until the app hangs. Any ideas why one is working and the other setTimeout isn't? Here's my javascript functions:
<script type="text/javascript">
function updateReachability() {
$.ajax({
url: 'updatePing.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
}
setTimeout(updateReachability, 3000);
function updatePerformance() {
$.ajax({
url: 'updatePerformance.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
}
setTimeout(updatePerformance, 300000);
function updateSiteList() {
$.ajax({
url: 'connector.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
}

Answer 1

you may want to wrap you function in the setTimeout itself, so that the settimeout is specific to that function and nothing else.
<script type="text/javascript">
function updateReachability() {
setTimeout(function() {
$.ajax({
url: 'updatePing.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
},3000);
May be this will work for you.

Answer 2

Don't know why this works but created a separate function that sets the two timeout values then called it on body onload:
<script type="text/javascript">
function updateSiteList() {
$.ajax({
url: 'connector.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
}
function updateReachability() {
$.ajax({
url: 'updatePing.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
}
function setTimeouts() {
setInterval(updateReachability, 3000);
setInterval(updatePerformance, 300000);
}
function updatePerformance() {
$.ajax({
url: 'updatePerformance.htm',
type: 'GET',
success: function(data) {
$('#site').html(data);
}
});
}