Persistant non-blocking operation problem

Question

When using asynchronous database calls with non-blocking methods, I am getting a persistant error on the CreateSQL method call - the error is "OIP-04153: Non-Blocking operation in progress". This is raised even though the database connection has been closed and restarted and no non-blocking operations called. The methods used are similar to the following example code:
Dim OraDatabase as OraDatabase
Dim OraStmt as OraSQLStmt
Dim stat as long
Dim OraSess as OraSession
Set OraSess = CreateObject("OracleInProcServer.XOraSession")
Set OraDatabase =OraSess.OpenDatabase("ExampleDb", "scott/tiger", 0)
'execute the select statement with NONBLOCKING mode on
set OraStmt = OraDatabase.CreateSQL ("update emp set sal = sal + 1000", ORASQL_NONBLK)
'Check if the call has completed
stat = OraStmt.NonBlockingState
if stat = ORASQL_STILL_EXECUTING
MsgBox "Cancelling the asynchronous operation that is underway"
     OraStmt.Cancel
End if
I cannot cancel the operation using OraStmt.Cancel because OraStmt Is Nothing!

Answer 1

Actually, that is not correct. All of the 48 port Gig-E line cards for the 6500 are oversubscribed; it does vary by the degree of oversubscription.
In a 6506 or a 6509 (with a Sup720) you have (2) 20 Gbps connections (per slot) to the fabric. With a WS-X6748-GE-TX you have a potential for 48 (Full Duplex) Gbps of traffic, but only 2 connections to the fabric. This yields an oversubscription rate of 1.2:1 (or 48:40) assuming a worst case scenario.
It should be noted that the 24 port 67xx cards are still oversubscribed as well, because they only have one connection to the fabric. There is a potential for 24 Gbps of traffic and only (1) 20 Gbps fabric connection, so it has an identical oversubscription rate.
By using only 24 of the 48 possible ports, depending on which ones you choose, you should be OK. But I do not know which ports use which fabric connection on the backplane, so I can't assist you in picking them.
It should be noted that in most environments it is unlikely every port will be a 100% utilized so the risk of dropping packets because of oversubscription is low.