Well, if it is slow when just navigating to a different line, it should not be the formulas that are causing that. Navigation between the lines triggers only RowSelected event, while formulas recalculation happens on RowUpdated. And you also said disabling the formulas did not help.

I'd suggest you to check FieldSelecting/RowSelected events. You can also try profiling with something like JetBrains dotTrace to understand what exactly takes time.

Thanks @Dmitrii Naumov what you explained makes absolute sense. To test it out I looked into Acumatica code and identified the RowSelected & RowUpdated event handlers as follows and temporarily ovrride them not to be executed as shown below. In my custom code I do not have any event handlers. But the issue still exist. Any though what other reason(s) may cause the issue?

  public class CostProjectionEntry_Extension : PXGraphExtension<CostProjectionEntry>
  {
    #region Event Handlers

    protected void PMCostProjection_RowSelected(PXCache cache, PXRowSelectedEventArgs e, PXRowSelected InvokeBaseHandler)
    {
      return;
    }


    protected void PMCostProjectionLine_RowSelected(PXCache cache, PXRowSelectedEventArgs e, PXRowSelected InvokeBaseHandler)
    {
      return;
    }    

    protected void PMCostProjection_RowUpdated(PXCache cache, PXRowUpdatedEventArgs e, PXRowUpdated InvokeBaseHandler)
    {
      return;
    }    

    #endregion
  }

Just for debugging purposes, please turn commitchanges to false on all fields and profile the speed. Does it help?

Hi @Dmitrii Naumov @Naveen Boga @rosenjon @Chris Hackett

All your comments were valid points but what causing the navigating bwtween the rows issue were some properties set on the grid as follows. When I removed the below properties, it seems to be fine and hopefully wont break something else:

<Prop Key="CallbackCommands.Navigate.CommitChanges" Value="True" />
<Prop Key="CallbackCommands.Navigate.RepaintControls" Value="All" />
<Prop Key="AutoCallBack.ActiveBehavior" Value="True" />
<Prop Key="AutoCallBack.Behavior.RepaintControlsIDs" Value="RevisionLogsGrid" />
<Prop Key="AutoCallBack.Behavior.BlockPage" Value="True" />

Still I have the performance issue when updating the subgrid I have added to the PMCostProjectionLine to retain the Revision Logs. If I find out what happens with rhis, I will share it here.