Environment:  Win32 dotNet 1.1, Windows 2000 Server Service Pack 4 with latest patches 
and  latest MDAC.  One server running MaxDB 
7.5.0.8, the other server running ASP.NET dotNet 1.1 as a ODBC client.  connection 
pooling turned on (always check this after driver install or 
upgrade, it always gets reset).

We were told by [EMAIL PROTECTED] that a driver deadlock was found and corrected in 
7.5.0.12!  It was Thomas' hope that 
this could be related to our long-stand deadlock issue with ASP.net under high 
concurrency.  We downloaded the 7.5.0.12 driver from 
ftp://ftp.sap.com/pub/sapdb/bin/win/ and gave it a try.

As an aside, our console apps (all single threaded) have not experienced driver 
problems.  We also have been able to work around the 
ASP.NET problem by forcing our application to avoid concurrent MaxDB access.   We 
"single file" all queries through a dotNet class that we 
developed.  This has put a performance hit on our application, but we have (mostly) 
overcome this by throwing faster hardware at the 
problem.

(Also of note - we have been unable to reproduce this ASP.NET deadlock with anything 
but our production user load.  If we could reproduce it 
with a simple test program, we would have published one long ago :) )


Install comment
==============
This driver is branded "SAP DB" instead of "MaxDB" by ODBC when installed.  We made 
sure to change our application to use that driver 
name.   Windows ODBC Control Panel reports the driver is dated 2004-04-15, which 
matches the file date - and we made double sure that we 
were using the correct new driver.  (We installed it on a test system that never had 
MaxDB/SAPDB on it and it was the same name/filedate).


good news:
============
We did testing and found a ASP.NET  memory leak we had with 7.5.0.08 driver was gone 
with this new driver.


Bad news
==========
We put the driver into production and let users pound on it with ASP.NET and within 2 
hours we had this error come up:

[MySQL MaxDB][SQLOD32 DLL][MaxDB] Unable to connect to data source;-807 Connection 
down, session released communication broken 
[not ok])

Again, this was with connection pooling enabled.  The problem lasted for a couple 
minutes and then corrected itself.  We have never seen this 
particular error before, so something new broken in this 7.5.0.12 driver?

The mailing list archive http://lists.mysql.com/maxdb/865 hits that such error is a 
internal driver issue?

Thank you.

  Stephen Gutknecht
  Full time traveler
  currently in Dallas, Texas USA




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