ITAGAKI Takahiro wrote: > We need to avoid using normal UPDATEs to increment counters > because it requires row-level exclusive locks and kills concurrency. > My idea was modifying heap tuples directly in pages: > > buffer = ReadBuffer(stats_rel, blknum); > LockBuffer(buffer, BUFFER_LOCK_EXCLUSIVE); > htup = PageGetItem(BufferGetPage(buffer), itemid); > statobj = ((char *) htup + htup->t_hoff); > statobj->calls++; > LockBuffer(buffer, BUFFER_LOCK_UNLOCK); > > It seemed to work in my test, but of course it is too dangerous. > (If we had supported ISAM-like storage engine, we might use it here.)
heap_inplace_update? -- Alvaro Herrera http://www.CommandPrompt.com/ PostgreSQL Replication, Consulting, Custom Development, 24x7 support -- Sent via pgsql-hackers mailing list (pgsql-hackers@postgresql.org) To make changes to your subscription: http://www.postgresql.org/mailpref/pgsql-hackers
