On 2020-Jun-24, Fujii Masao wrote: > On 2020/06/24 8:39, Alvaro Herrera wrote:
> > I think we should publish the value from wal_keep_segments separately > > from max_slot_wal_keep_size. ISTM that the user might decide to change > > or remove wal_keep_segments and be suddenly at risk of losing slots > > because of overlooking that it was wal_keep_segments, not > > max_slot_wal_keep_size, that was protecting them. > > You mean to have two functions that returns > > 1. "current WAL LSN - wal_keep_segments * 16MB" > 2. "current WAL LSN - max_slot_wal_keep_size" Hmm, but all the values there are easily findable. What would be the point in repeating it? Maybe we should disregard this line of thinking and go back to Horiguchi-san's original proposal, to wit use the "distance to breakage", as also supported now by Amit Kapila[1] (unless I misunderstand him). [1] https://postgr.es/m/CAA4eK1L2oJ7T1cESdc5w4J9L3Q_hhvWqTigdAXKfnsJy4=v...@mail.gmail.com -- Álvaro Herrera https://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Remote DBA, Training & Services
