Lousy Query performance due to sp_cursoropen -
04-12-2006
, 08:46 AM
Hi
After running the MS performance toolbox, notably the track_wait_states
sproc, on an old VB6 / ADO COM+ application, it seemed that the
overwhelming wait culprit was OLEDB. (I have my doubts - believe more
to do with the overhead of MSDTC)
As a result, I want to investigate changing to an ODBC DSN to see if
the waits shifted elsewhere.
The APP works with ODBC, but the App is about 10 x slower, due to the
sp_cursoropen / sp_cursorfetch calls created by the driver.
(sp_cursoropen sometimes takes up to 30 seconds to execute a query
which takes <100ms to run on ISQL/W or via OLEDB). sp_cursorfetch is
near instantaneous.
What gives with sp_cursoropen? It seems only a couple of queries get
stuck like this - most sp_cursoropen's complete within a few
milliseconds.
Using MDAC2.8, VB6 COM+ components under DTC, SQL 2000 on Windows 2003.
Regards
Stuart |