This is not expected behavior of RadGrid but I am not sure what exactly could be causing it. Can you please share your grid declaration and data-binding logic, so that we can look for possible issues in them.
You can take a look at this demo of RadGrid, where it uses client hierarchy loading and it displays just the right number of records:
Client-side Hierarchy Loading
Also, in the meantime, check whether you have more than one PageSize settings inside your grid and tableview which could be in conflict, e.g. if you have page size setting for each GridTableView, you should not set a number in the RadGrid tag.
All the best,
the Telerik team
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