The customer confirmed the size for the same user document (Administrator) in their Domino directory (names.nsf) by the following two methods, but each way show a different size.
Method 1). Show Document Property from view
Open names.nsf, move to user document view, select the line for Administrator, click mouse right button, and select "Document Property" from context menu,
then the user found the document size show in the "Document Property" dialog is 3466 Bytes ( This screen shot ScreenShot1.png is attached in this ticket)
Method 2) Open the document and then show Document property
Open names.nsf, move to user document view, open Administrator's user document, then show Document Property Dialog,
then the user found the document size show in the "Document Property" dialog is 7208 Bytes ( This screen shot ScreenShot2.png is attached in this ticket)
According to HCL GSA CWP WW's following answer, the above difference is work as design:
Refer to: https://help.hcltechsw.com/dom_designer/9.0.1/appdev/H_DOCLENGTH.html
Documents that are open typically use more storage than documents that are closed.
The value returned for @DocLength may vary depending on whether it is running in an open document or a closed document; for example, a document selected at the view level.
Some size difference is expected.
When the doc is open on a form, the size depends on the new the intermediate/transient fields computed/computed-for-displayed whilst the doc is open by the form.
What you see at the view level is the real approximation of user-data size.
But different size were shown in the same document property, this will make end user confused. So please show the same size no matter how the document property is opened and whether the document is opened or not.