On 2022-03-18 18:14:52 +0300, Maxim Orlov wrote: > Subject: [PATCH v22 3/6] Use 64-bit pages in SLRU > > This is one step toward 64-bit XIDs.
I think this should explain in more detail why this move is done. Neither the commit message nor the rest of the thread does so afaics. It's not too hard to infer, but the central reason behind a patch shouldn't need to be inferred.