Low Performances in Expand All Groups

[Yolanda]

We are experimenting low time response when we try to expand groups in our gridview.

In our exemple we have around 700 entries (~4MB) to be shown in the grid with one level group, nowadays we only have 3 groups. Expanding all groups takes around 7 seconds.

We are planning to use the grid to show about 17000 entries (~23MB) in 5 grouping levels and we are really afraid about the spent time when expanding groups. A stimated time of 20 seconds isn't acceptable for our client , so how can performaces be improved?

We already have problems about scrolling performances and if we add low performances in expanding groups the client will be really really unhappy....

Regards
  Yolanda

[Nedyalko Nikolov]

Hi Yolanda,

Indeed with the current version of RadGridView there is a significant performance hit with grouping more levels (>3) and when AutoExpandGroups is true. The problem comes from the fact that in that case RadGridView iterates all items (groups and subgroups) in order to calculate a proper extend height (used for scrolling). We have plans to sacrifice calculating this information and this will result in a great performance boost while scrolling with such cases will be a little bit weird (but expected). What I mean initially only visible groups will be expanded (so only their items will be iterated), then when scroll reached new group this group will automatically expand due to AutoExpandGroups property value but this will reflect in a greater extend height and scroll thumb will jump a little.
Same behavior like doing this manually - expand first group and scroll to the end, second group is not expanded while expanding it will enlarge extend height. We are doing our best to provide this optimization as soon as possible, but I cannot commit with any specific date or release.
Sorry for the inconvenience caused.

Greetings,
Nedyalko Nikolov
the Telerik team

[Daní]

Hello,

Any advance in this issue? I have a GridView with about 1200 items and AutoExpandGroups property set to "True" and is consuming a lot of memory and cpu Profiling my application I can see that I have about 1200 GridViewRow instances. I'm using 2010.3.1314.1040 version.

[Vlad]

Hi,

 Please verify if the grid is not measured with infinity. 

Best wishes,
Vlad
the Telerik team

[Daní]

Hi Vlad,

I don't think so. GridView is inside a Grid with two RowDefinitions, first one has height set to auto but the second one has height set to star and the GridView is placed on the second row. The container Grid is the LargeContent of a RadFluidContent placed inside a RadTileViewItem. The RadTileView is the content of a RadWindow showed when user press a button.

[Daní]

Hi Vlad,

any word about this issue? How can i ensure that RadGridView is measured with infinity?

Thanks

[Vlad]

Hello,

 The easiest way to check this is to verify if RadGridView have vertical scrollbar. 

Greetings,
Vlad
the Telerik team

[Daní]

Hi Vlad,

Yes, RadGridView has vertical scroll bar. So, have you sloved this issue: low perfomance when AutoExpandGroups property is set to true ,or is there something I'm doing wrong?

[Vlad]

Hello,

Can you send us runnable example where we can reproduce this?

All the best,
Vlad
the Telerik team

[Daní]

Hello Vlad,

I will open inmediately a support ticket with an example

Thanks

[Vlad]

Hello Daní,

 I've checked your project and I believe that this slowness is mainly because RadTileView. I'm not sure if you are aware however we've managed to optimize the component greatly and to illustrate you this I've added reference to our Q1 2011 Beta binaries to your project (attached to your support ticket).

 The official release of Q1 2011 will be this week.

Greetings,
Vlad
the Telerik team