It looks like pg_walinspect's GetWALRecordsInfo() routine doesn't take sufficient care with memory management. It should avoid memory leaks of the kind that lead to OOMs whenever pg_get_wal_records_info_till_end_of_wal() has to return very many tuples. Right now it isn't that hard to make that happen, even on a system where memory is plentiful. I wasn't expecting that, because all of these functions use a tuplestore.
More concretely, it looks like GetWALRecordInfo() calls CStringGetTextDatum/cstring_to_text in a way that accumulates way too much memory in ExprContext. This could be avoided by using a separate memory context that is reset periodically, or something else along the same lines. -- Peter Geoghegan
