I think it's really a more convenient way to collect wal usage information, with it we can query when I want. Several points on my side:
1. It will be nice If you provide a chance to reset the information in WalStats, so that we can reset it without restart the database. 2. I think 'wal_write_backend' is mean wal write times happen in backends. The describe in document is not so clear, suggest rewrite it. 3. I do not think it's a correct describe in document for 'wal_buffers_full'. 4. Quite strange to collect twice in XLogInsertRecord() for xl_tot_len, m_wal_records, m_wal_fpi. 5. I notice some code in issue_xlog_fsync() function to collect sync info, a standby may call the issue_xlog_fsync() too, which do not want to to collect this info. I think this need some change avoid run by standby side. Regards, Highgo Software (Canada/China/Pakistan) URL : www.highgo.ca EMAIL: mailto:movead(dot)li(at)highgo(dot)ca