Re: [PERFORM] insert performance for win32
Tom Lane <[email protected]> Wed, 07 Sep 2005 11:02:13 -0400
| Newsgroups | gmane.comp.db.postgresql.devel.win32,gmane.comp.db.postgresql.performance |
|---|---|
| Message-ID | <[email protected]> |
"Merlin Moncure" <[email protected]> writes: > ok, I've been in crunching profile profile graphs, and so far have been > only been able to draw following conclusions. > For bulk, 'in-transaction' insert: > 1. win32 is slower than linux. win32 time for each insert grows with # > inserts in xact, linux does not (or grows much slower). Win32 starts > out about 3x slower and grows to 10x slower after 250k inserts. Just to be clear: what you were testing was BEGIN; INSERT ... VALUES (...); repeat insert many times COMMIT; with each statement issued as a separate PQexec() operation, correct? Was this set up as a psql script, or specialized C code? (If a psql script, I wonder whether it's psql that's chewing the time.) > 2. ran a 50k profile vs. 250k profile. Nothing jumps out as being > slower or faster: most time is spent in yyparse on either side. From > this my preliminary conclusion is that there is something going on in > the win32 api which is not showing in the profile. Hmm. Client/server data transport maybe? It would be interesting to try inserting the same data in other ways: * COPY from client * COPY from disk file * INSERT/SELECT from another table and see whether you see a similar slowdown. regards, tom lane ---------------------------(end of broadcast)--------------------------- TIP 1: if posting/reading through Usenet, please send an appropriate subscribe-nomail command to [email protected] so that your message can get through to the mailing list cleanly