Re: DBD::Sybase misleads me?

The sp_configure option is dynamic, but only affects future connections. It
is an upper limit, and the client has to specifically request the larger
packet size to get it. Otherwise the default 512 byte packet size is used.

Michael




Extranet
alexander@xxxxxxxx - 23/06/2006 14:48

To: matthew.persico

cc: dbi-users


Subject: Re: DBD::Sybase misleads me?


What does "sp_configure max network packet size" affect? The current
connection or the entire server?

If it's the connection, it simply can't work: The commercial app is
forked, and has no relation to DBI's connection, so it creates and uses
its own connection (though it seems to fail to set the desired size by
itself).

It it's the entire server, does the client library assume a certain size
or does it asks the server for the current max. packet size?


(And why would you want to change that setting?)

Alexander

On 23.06.2006 14:36, Matthew Persico wrote:

I have a commercial program that accesses a Sybase 12.5 server. It has
an option to change the packet size of the communucation frame with
the server, but you have to know what size you want.

Sooo, in my perl program, I connect to the database with DBD::Sybase,
execute a
sp_configure 'max network packet size' and then I system() the
commercial program with the argument -zpkt=whatever I got back.

Occasionally, the program responds with

DB-Lib ERROR: 20201: Packet size of 16384 not supported -- size of
13824 used instead. severity is 1

The program then dies, but that is their problem - it should
disconnect and reconnect properly and I will register te bug with them

My question is this what causes this? One minute 16384 is ok and the
next its not. DBD::Sybase is CT-LIb based and their program is DB-Lib
based. Is that a problem?
--
Matthew O. Persico



--
Alexander Foken
mailto:alexander@xxxxxxxx http://www.foken.de/alexander/




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