Hey Greg... I'm having a similar issue with how Windows 10 v1809 manages the Pagefile size on my OS SSD... In my particular case Windows forces a very large Pagefile on C: Drive... Initially it started at 4gb right after I upgraded to v1809... Then jumped up yo 9gb about a month ago... And currently Windows keeps it at 11 gb... FYI... My rig has 16gb G.Skill FlareX 3200-DDR4 kit...
I am however, able to manually set the Pagefile to a fixed min/max value... But that in turn keeps causing a few Steam games to freeze for some weird reason... Specially since my dGPU is an ASUS DUAL OC AMD RX-580-o4gb... For now though I opted for moving the Pagefile to my Secondary 1 TB HDD... Windows maxed out the Pagefile at 32gb though... I manually have it set now at 16gb min/max...