You may have noticed a decrease in performance between space drawings in previous versions of AutoCAD Architecture 2023 toolset and in the current version even if you have not made any changes to the drawings.
To workaround, check if your drawing contains spaces bounded by objects in external references. In previous versions of the software, a manual update was necessary to propagate changes in the external reference’s boundary objects to associative spaces in the current drawing; now changes from external references are automatically updated, if the automatic update of associative spaces is activated. This can result in a noticeable performance lag. Deactivate the automatic update.
Another possibility can be that when you are converting drawings with xrefs and associative spaces from a previous version, the first time the host drawing is opened will be accompanied by a noticeable performance hit. This is however only a one-time effect; once the host drawing and its associated xref drawings have been and opened and saved with the current version, the performance will be improved for all future sessions.