After reading through the referenced document, I have this question. How do I determine the predominant message size? What tools and techniques? I have a GIS application with a large number of blobs, so I think there are probably a fair number of large messages. - Eric Hutchinson _____ From: oracle-l-bounce@xxxxxxxxxxxxx [mailto:oracle-l-bounce@xxxxxxxxxxxxx] On Behalf Of Rich Jesse Sent: Thursday, January 29, 2009 9:03 AM To: oracle-l@xxxxxxxxxxxxx Subject: Re: SDU setting being ignored? YES!!! [29-JAN-2009 10:55:52:757] nsopen: lcl[0]=0xf4ffefff, lcl[1]=0x102000, gbl[0]=0xfabf, gbl[1]=0x0, tdu=32767, sdu=8192 That placement in the tnsnames.ora is indeed the key. And now that you've shown me, I've found an example of it in the docs as well: http://download.oracle.com/docs/cd/B14117_01/network.101/b10775/performance. htm#i1006332 Thanks, Tim!!! Rich > On the client-side TNS connect-string, I've always specified the SDU clause > within the first level of the DESCRIPTION, outside both the > ADDRESS_LIST/ADDRESS clause as well the CONNECT_DATA clause. > > So, using your example... > MYDBWAN= > (DESCRIPTION=(SDU=8192)(ADDRESS=(PROTOCOL=TCP)(HOST=myhost)(PORT=1526)) > (CONNECT_DATA=(SERVICE_NAME=mydb))) Hope this helps... > Tim Gorman consultant - Evergreen Database Technologies, Inc. P.O. Box