On Fri, Jan 23, 2004 at 05:58:33PM -0300, Martín Marqués wrote: > Tom, could you give a small insight on what occurred here, why those 8k of zeros > fixed it, and what is a "WAL replay"?
If I may ... - the disk filled up - Postgres registered something in WAL that required some commit status (WAL log space is preallocated on disk, so this didn't fail) - the clog code tried to store information about the commit bits, but noticed that it needed to extend the clog file. - the extension failed because the disk was full - the server went down and a WAL replay was in order, but ... - the WAL replay could not be done because the code tried to read a commit status in pg_clog that wasn't there (some time later) - Chris emptied up some space and extended the clog - WAL replay completed, reading an "uncommitted" status from the clog. Here, "clog" is the "commit log", an area which indicates for each transaction whether it committed or aborted. A WAL replay is the operation of bringing the data files (tables, indexes, etc) up to date by reading the "Write-ahead log" (WAL). Tom's answer will be undoubtly better ... -- Alvaro Herrera (<alvherre[a]dcc.uchile.cl>) "¿Que diferencia tiene para los muertos, los huérfanos, y aquellos que han perdido su hogar, si la loca destrucción ha sido realizada bajo el nombre del totalitarismo o del santo nombre de la libertad y la democracia?" (Gandhi) ---------------------------(end of broadcast)--------------------------- TIP 6: Have you searched our list archives? http://archives.postgresql.org