I think that also my problem is related to the MeasureOverride because if I set a fixed heigth for the rows I get a huge performance gain

Matt,

I attached the VS profiler screen shot, looks like it has something to do with measuring and sizing.

I've tried Snoop and confirmed that the visual tree only contains visible records/cells.

Pleases advise, thanks.

10.3 does not improve it.

I have another simlar problem about problem.

I found when I change datasource and if the original datasource is not null, grid will travel all item in the datasource. It is a very big problem. Is this improve in 10.3?

The code is in OnSourceCollectionReset in RecordManager.cs

     if ( DataSourceResetBehavior.ReuseRecordsViaEnumerator == resetBehavior
      && sourceList != null && this._unsortedRecords.Count == newCount )
                    {
                        inSameOrder = true;

                        i = 0;

                        foreach (object source in sourceList)
                        {
                            // JJD 1/13/08
                            // Bypass XmlComments
                            if (source is System.Xml.XmlComment)
                                continue;

                            DataRecord record = (DataRecord)this._unsortedRecords.SparseArray.GetItem(i, false);
                            if (null != record)
                            {
                                if (!record.IsDataItemEqual(source))
                                {
                                    inSameOrder = false;
                                    break;
                                }
                            }

                            i++;
                        }
                    }

I recommend using the latest version 10.3.

Sam