On Mon, Dec 3, 2018 at 11:15 AM John Naylor <jcnay...@gmail.com> wrote: > > On 12/3/18, Amit Kapila <amit.kapil...@gmail.com> wrote: > > On Mon, Dec 3, 2018 at 9:46 AM Amit Kapila <amit.kapil...@gmail.com> wrote: > >> > >> On Thu, Nov 29, 2018 at 3:07 PM John Naylor <jcnay...@gmail.com> wrote: > >> > > >> > > v8 code: > > +fsm_local_set(Relation rel, BlockNumber new_nblocks) > > +{ > > + BlockNumber blkno, > > + cached_target_block; > > + > > + /* > > + * Mark blocks available starting after the last block number we have > > + * cached, and ending at the current last block in the relation. > > + * When we first set the map, this will flag all blocks as available > > + * to try. If we reset the map while waiting for a relation > > + * extension lock, this will only flag new blocks as available, > > + * if any were created by another backend. > > + */ > > + for (blkno = fsm_local_map.nblocks; blkno < new_nblocks; blkno++) > > + fsm_local_map.map[blkno] = FSM_LOCAL_AVAIL; > > > > v9 code: > > +static void > > +fsm_local_set(Relation rel, BlockNumber nblocks) > > +{ > > + BlockNumber blkno, > > + cached_target_block; > > + > > + for (blkno = 0; blkno < nblocks; blkno++) > > + fsm_local_map.map[blkno] = FSM_LOCAL_AVAIL; > > > > What is the reason for the above code change in the latest patch version? > > Per your recent comment, we no longer check relation size if we waited > on a relation extension lock, so this is essentially a reversion to an > earlier version. >
fsm_local_set is being called from RecordAndGetPageWithFreeSpace and GetPageWithFreeSpace whereas the change we have discussed was specific to GetPageWithFreeSpace, so not sure if we need any change in fsm_local_set. > Keeping v8 would have the advantage that it'd be > simple to change our minds about this. Do you have an opinion about > that? > > > It would be good if you add few comments atop functions > > GetPageWithFreeSpace, RecordAndGetPageWithFreeSpace and > > RecordPageWithFreeSpace about their interaction with local map. > > Good idea, will do. > Thanks. -- With Regards, Amit Kapila. EnterpriseDB: http://www.enterprisedb.com