ParamQuery grid support forum

General Category => Help for ParamQuery Pro => Topic started by: mond2000 on February 07, 2016, 03:04:31 am

Title: Memory leak on refreshDataAndView ?
Post by: mond2000 on February 07, 2016, 03:04:31 am: Dear Sir,

I noticed, that the memory usage is increased on each call of refreshDataAndView or even refresh,

below, a sample code,
Thank you for your help.

/***************************/

<html>
<head>
<title>test</title>

<link rel="stylesheet" href="http://ajax.googleapis.com/ajax/libs/jqueryui/1.9.2/themes/base/jquery-ui.css" />
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.8.3/jquery.min.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.9.2/jquery-ui.min.js"></script>


<link href="Lib/ParamQueryProVersion/pqgrid.min.css" rel="stylesheet" />
<script src="Lib/ParamQueryProVersion/pqgrid.min.js"></script>

</head>
<body style="overflow:auto; margin-left:0px;margin-top:0px;" id ="test" >
<div id="grid_array" style="margin:auto;"></div>

<script>
var data = [
[1, 'Line 0','0'],
[2, 'line 1','1'],
[3, 'line 2','2']
];

var obj = { width: 700, height: 300, title: "Grid From Array", numberCell:{resizable:true, title: "#"},
editable: false, scrollModel: { autoFit: true }, flexWidth: true, showBottom:false, resizable: true };

obj.colModel = [
{ title: "Rank", width: 100, dataType: "integer" },
{ title: "Line", width: 200, dataType: "string" },
{ title: "Num", width: 200, dataType: "integer" }
];
obj.dataModel = { data: data };

var $grid = $("#grid_array").pqGrid(obj);
var k = 0;

function Upd_Grid_1(k) {
data[2][2] = k;
$("#grid_array").pqGrid("refreshDataAndView");

k = k + 1;
setTimeout(function () { Upd_Grid_1(k); }, 10);
}

Upd_Grid_1(0);
</script>
</body>
</html>
Title: Re: Memory leak on refreshDataAndView ?
Post by: paramvir on February 08, 2016, 09:01:13 am: ParamQuery grid Pro is proactively tested against memory leaks.

Consumed Memory increases in your test case because it calls refreshDataAndView() in an infinite loop without a pause, which prevents the browser to do garbage collection of dead nodes accumulated in every refresh cycle.

Any refresh* methods are better not to be used in a loop as noted in the API.
Title: Re: Memory leak on refreshDataAndView ?
Post by: mond2000 on February 08, 2016, 01:04:50 pm: Thank you for your reply,
Our application requires an update of six grids each 2 seconds.
Any suggestion to avoid the mentioned problem is welcome.
Thank you for your help.
Title: Re: Memory leak on refreshDataAndView ?
Post by: paramvir on February 08, 2016, 01:50:43 pm: Since there are six grids that leaves 1/3 second for every grid. It would be helpful to check the data first for changes and do a refresh only when required.

Please follow this:

1) use virtual mode. { virtualX: true, virtualY: true }. The number of nodes and refresh time is less in virtual mode.

2) Try to increase the time interval if possible.

3) use the latest version of pqGrid.