On 20th of July 2020, Fujii Masao committed patch:
Rename wal_keep_segments to wal_keep_size. max_slot_wal_keep_size that was added in v13 and wal_keep_segments are the GUC parameters to specify how much WAL files to retain for the standby servers. While max_slot_wal_keep_size accepts the number of bytes of WAL files, wal_keep_segments accepts the number of WAL files. This difference of setting units between those similar parameters could be confusing to users. To alleviate this situation, this commit renames wal_keep_segments to wal_keep_size, and make users specify the WAL size in it instead of the number of WAL files. There was also the idea to rename max_slot_wal_keep_size to max_slot_wal_keep_segments, in the discussion. But we have been moving away from measuring in segments, for example, checkpoint_segments was replaced by max_wal_size. So we concluded to rename wal_keep_segments to wal_keep_size. Back-patch to v13 where max_slot_wal_keep_size was added. Author: Fujii Masao Reviewed-by: Álvaro Herrera, Kyotaro Horiguchi, David Steele Discussion: https://email@example.com
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