Ajax responses very slow.

[anubhavjha]

Hi Friends,

I have a web application through which, the ajax is used to post the data onto the server and return the results. When i alert the xmlhttp.readystate sometimes it takes long time, that the process looks like freezing and sometimes its done very quickly as it is designed to.

I checked by alerting xmlhttp.readystate.

sometimes i get response 1,2 ,3 4 as the alert box quickly.
and sometimes i just get 1 and then nothing happens.

Has any one experienced the same.

Regards,
Anubhav

[dlite922]

maybe problem with your PHP file. Try to send the same variables to the file through a manual call (enter it in your browser address bar), it maybe that this file never gets back.

Only thing I can think of that causes this.



Dan

[Dheeraj Joshi]

Just try to get the response from a dummy PHP file...

If the response time is same for every call.. then as dlite922 told its a problem with your PHP... Prpbably you need to fix some issues..

Regards
Dheeraj Joshi

I did not faced such problems.

[anubhavjha]

I checked that , but if i send the variables directly to the php file as the action in the form tag, it goes out fine. I am using IE 7.0 and sometimes it works fine and sometimes does not work.

[Dheeraj Joshi]

Check it in FF(Fire Fox)... I got some problem when i used AJAX call in IE(Though not similar)...

Regards
Dheeraj Joshi

[anubhavjha]

Hi Dheeraj,, even firefox and ie shows the same response. and there is a javascript code written that the web application cannot be used on a firefox. can you think of something else.

[dgreenhouse]

Do think that multiple requests are being fired off?

If so, that may part of the bottleneck.

If I remember correctly, IE will open only 2 connections at once.

You might also want to add a timeout in your Ajax callback function so the application is more responsive.

http://ajax.sys-con.com/node/352578

Post your httpRequest and callback function.

[gits]

that seems more to be a problem with the JavaScript-code then with the php-code. could you post the JavaScript-code that is relevant for the ajax-call?

kind regards

[Dheeraj Joshi]

Ok.... I dont know any other solution.

Just post the Java script like GITS told... It may be the culprit....

Regards
Dheeraj Joshi

[anubhavjha]

@dgreenhouse
Thank you for your reply.

I dont know to check if the multiple requests are being fired off.can you pls provide detail on it.

[anubhavjha]

First i was using the following codes:-

The function is called on submit of a button.

function submitform()
{
result=0;
//gettting the form values;
var requestid=document.getElementById("requestid").value;
var sdenggname=document.getElementById("sdenggname").value;
var sla=document.getElementById("sla").value;
var helpdesk_comments=document.getElementById("helpdesk_comments").value;
var calltype=document.getElementById("calltype").value;
//validation part
if(sdenggname=="--"||sla=="--"||helpdesk_comments==""||calltype=="--")
{
alert("Please make sure that you have filled in all the fields");
return false;
}
//validateion part end
var domain=document.domain;
 
var url = "http://"+domain+"/crfportal/assignhelpdeskcalls_submit.php"; //url
 
var params = "requestid="+requestid+"&sdenggname="+sdenggname+"&sla="+sla+"&helpdesk_comments="+helpdesk_comments+"&calltype="+calltype; //generating parameters
 
//displaying the user with a statment while the request is being sent.
document.getElementById("d1").innerHTML="<table><tr><td>Please wait while the call is getting assigned</Td></tr></table>"
var xmlhttp=false;
//alert(params);
/*@cc_on @*/
/*@if (@_jscript_version >= 5)
// JScript gives us Conditional compilation, we can cope with old IE versions.
// and security blocked creation of the objects.
 try {
  xmlhttp = new ActiveXObject("Msxml2.XMLHTTP");
 } catch (e) {
  try {
   xmlhttp = new ActiveXObject("Microsoft.XMLHTTP");
  } catch (E) {
   xmlhttp = false;
  }
 }
@end @*/
if (!xmlhttp && typeof XMLHttpRequest!='undefined') {
    try {
        xmlhttp = new XMLHttpRequest();
    } catch (e) {
        xmlhttp=false;
    }
}
if (!xmlhttp && window.createRequest) {
    try {
        xmlhttp = window.createRequest();
    } catch (e) {
        xmlhttp=false;
    }
}
      //alert("xmlhttp"+xmlhttp);
 try{xmlhttp.open("POST", url, true);}
 catch(e)
 {
      alert("some error");
}
 
//Send the proper header information along with the request
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
xmlhttp.setRequestHeader("Content-length", params.length);
xmlhttp.setRequestHeader("Connection", "close");
 
xmlhttp.onreadystatechange = function() {//Call a function when the state changes.
 
    if(xmlhttp.readyState == 4 && xmlhttp.status == 200) {
 
        result=xmlhttp.responseText;
        if(result!=0)
        {
        window.location="assignsdcalls.php?refresh=1";
        }
    }
}
xmlhttp.send(params);
}

Then i changed the above code to the following:

function submitform()
{
result=0;
//gettting the form values;
var requestid=document.getElementById("requestid").value;
var sdenggname=document.getElementById("sdenggname").value;
var sla=document.getElementById("sla").value;
var helpdesk_comments=document.getElementById("helpdesk_comments").value;
var calltype=document.getElementById("calltype").value;
var status=document.getElementById("reqstatus").value;
var sdenggcomment=document.getElementById("sdenngcomments").value;
//document.form1.submit();
//validation part
if((status=='Closed'||status=='closed')&& sdenggcomment=="")
{
alert("The call under closed status need to have comment")
return false;      
}
if(sdenggname=="--"||sla=="--"||helpdesk_comments==""||calltype=="--")
{
alert("Please make sure that you have filled in all the fields");
return false;
}
//validateion part end
//setTimeout("",1250);
document.getElementById("assigncall").disabled=true;
var domain=document.domain;
 
var url = "http://"+domain+"/crfportal/assignhelpdeskcalls_submit.php"; //url
//var url1 = "http://172.16.140.15/crfportal/assignhelpdeskcalls_submit.php"; //url to be used when the 172.16.140.15 is there.
var params = "requestid="+requestid+"&sdenggname="+sdenggname+"&sla="+sla+"&helpdesk_comments="+helpdesk_comments+"&calltype="+calltype+"&status="+status+"&sdenggcomment="+sdenggcomment+ "&rand=" + (new Date()); //generating parameters
document.getElementById("d1").innerHTML="<table><tr><td>Please wait while the call is getting assigned</Td></tr></table>"
var xmlhttp=false;
xmlhttp=new ajaxRequest();
 try{xmlhttp.open("POST", url, true);}
 catch(e)
 {
try{xmlhttp.open("POST", url1, true);}
catch (e)
     {
      alert("some error");}
 }
 
//Send the proper header information along with the request
xmlhttp.setRequestHeader("Content-type", "application/x-www-form-urlencoded");
//xmlhttp.setRequestHeader("Content-length", params.length);
//xmlhttp.setRequestHeader("Connection", "close");
 
xmlhttp.onreadystatechange = function() {//Call a function when the state changes.
//alert(xmlhttp.readyState);
 
    if(xmlhttp.readyState == 4 && xmlhttp.status == 200) {
        result=xmlhttp.responseText;
        if(result!=0)
        {
        //document.getElementById("d1").innerHTML="<table><tr><td>"+result+"</Td><td><a href='assignsdcalls.php'>Assign another calls</a></td></tr></table>";
//document.getElementById("assigncall").disabled=true;
window.location="assignsdcalls.php?refresh=1";
        }
    }
}
xmlhttp.send(params);
 
}

The function ajaxrequest is defined as follows:-

function ajaxRequest(){
 var activexmodes=["Msxml2.XMLHTTP", "Microsoft.XMLHTTP"] //activeX versions to check for in IE
 if (window.ActiveXObject){ //Test for support for ActiveXObject in IE first (as XMLHttpRequest in IE7 is broken)
  for (var i=0; i<activexmodes.length; i++){
   try{
    return new ActiveXObject(activexmodes[i])
   }
   catch(e){
    //suppress error
   }
  }
 }
 else if (window.XMLHttpRequest) // if Mozilla, Safari etc
  return new XMLHttpRequest()
 else
  return false
}

when i give alert on xmlhttp.readystate sometimes i get alert as 1234 very quickly and sometimes it just stops after 1.

Also after going through my code, if you see any thing which is not a good programming practice. please let me know.