On 17 September 2012 15:59, Robert Haas <robertmh...@gmail.com> wrote: > On Sun, Sep 16, 2012 at 2:54 PM, Simon Riggs <si...@2ndquadrant.com> wrote: >> Fix bufmgr so CHECKPOINT_END_OF_RECOVERY behaves as a shutdown checkpoint. >> Recovery code documents clearly that a shutdown checkpoint is executed at >> end of recovery - a shutdown checkpoint WAL record is written but the buffer >> manager had been altered to treat end of recovery as a normal checkpoint. >> This bug exacerbates the bufmgr relpersistence bug. >> >> Bug spotted by Andres Freund, patch by me. > > I am confused by this patch. It seems to me that the effect of this > patch is to force unlogged buffers to be written at end-of-recovery as > well as at shutdown. But, barring bugs elsewhere, there shouldn't be > any unlogged buffers in shared_buffers at end-of-recovery, so this > won't make any difference at all.
There shouldn't be, but this coding is the fail safe way. > Am I missing something? If you or others do, this will save us. > Maybe what we should do is - if this is an end-of-recovery checkpoint > - *assert* that the BM_PERMANENT bit is set on every buffer we find. > That would provide a useful cross-check that we don't have a bug > similar to the one Jeff already fixed in any other code path. Safety net is needed there, not an Assert. -- Simon Riggs http://www.2ndQuadrant.com/ PostgreSQL Development, 24x7 Support, Training & Services -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
