Hi community, I was reading about background process, but especially about Background writer, I also found an article on this website https://postgreshelp.com/postgresql-background-writer/. I understood that the background writer flushed new or modified data from shared buffers to disk. I also understood that background writer is based on three features bgwriter, bgwriter_1ru_maxpages, bgwriter_1ru_multiple. That article said that bgwriter_1ru_multipler if the value is set to 2, and if incoming buffers pages are 10, dirty buffers will be cleared until there are 20 buffers available or until bgwriter_1ru_maxpages. I have several questions. First, where should be available buffers on disk or shared buffers for applying bgwriter_1ru_multiple?, second when there is new or modified data is written in the two places on WAL and shared buffers both same time? and finally if we increase bgwriter_1ru_maxpage andbgwriter_1ru_multiple will there fewer files on pg_wal?