PRB: MS Oracle Driver 1.0 Limitation in MTS Environment
Article ID: 180190
Article Last Modified on 5/6/2001
APPLIES TO
- Microsoft Transaction Services 1.0
- Microsoft Visual C++ 5.0 Enterprise Edition
- Microsoft Visual C++ 5.0 Professional Edition
This article was previously published under Q180190
SYMPTOMS
When the Microsoft Oracle ODBC driver version 1.0 (build 2.00.006325) is
used, concurrent queries performed by objects in the same Microsoft
Transaction Server (MTS) package may exhibit slow performance.
CAUSE
Version 1.0 of the Microsoft Oracle ODBC driver is thread safe at the
driver level. The ODBC driver can only handle one request at a time. This
means that only one MTS client can access the driver at a time while the
others wait. If multiple clients are simultaneously trying to run queries,
performance may be slow. If the queries are long or there are a lot of
clients, performance could be seriously impacted.
MTS assigns a separate thread to each client activity. Only one thread can
access the driver at a time while the others must wait for the current
request to finish. This is an issue for other multithreaded environments
such as Internet Information Server (IIS) as well.
NOTE: This article assumes that the Oracle ODBC driver is being used in
separate non-transactional MTS components.
RESOLUTION
Currently there is no workaround for the problem.
STATUS
Microsoft is researching this problem and will post new information here in
the Microsoft Knowledge Base as it becomes available.
Keywords: kbprb KB180190