I am trying to make an ajax call in angularjs application. but randomly i am getting this caution says "Provisional headers are shown" and whenever this caution comes in debugger console I am getting very slow response from server (about 30 to 45 sec). and its happening around 6 times in 10 times trial period.

this is my angularjs piece of code:-

var request = $http({
                  method:"post",
                  url:"/getdata.php",
                  data:filterpara,                              
                  headers: {'Content-Type' : 'application/x-www-form-urlencoded'}                       
            }); 

        request.success(function(data){ 

                    console.log(data);

        });

This type of piece of code I am using number of times in different controllers. but randomly same issue is coming in different controllers as well. i am unable to figure out why this is happening?

I have also tried the solutions which is already provided by these links (but no luck) :-

Node js / Angular js - CAUTION: Provisional headers are shown (this kind of problem I am facing)

"CAUTION: provisional headers are shown" in Chrome debugger