performance problem with fetch using 8.1.7 32-bit client to access a 64-bit server

We are running 8.1.7.4 64-bit Oracle on Solaris 8/sparc3. We have a client which was compiled on a 32-bit sparcII platform. We find that when we run multiple instances of the client we find that it doesn't scale very well, even though the product vendor believes that it should and we have evidence to prove this in different sites.

We have already spent a lot of effort tuning the server and we not believe that it is well tuned. The server spends 90% of it's time idle. We have found that the client also spends about 90% of its time sleeping even though it has work to do, and there are plenty of free resources (only 25% of 24 CPUs are utilised, 40% of free memory, and IO is healthy).

When we dig deeper into what the client is doing using pstack, we find that that it spend most of its time fetching from various cursor and specifically in the read function. An example stack trace is below:

When we dig deeper into what the client is doing using pstack, we find that that it spend most of its time fetching from various cursor and specifically in the read function. An example stack trace is below: Received on Mon Feb 09 2004 - 02:14:39 CST