On Tue, 17 Jun 2003 10:09:02 +0200
"Zabach, Elke" <[EMAIL PROTECTED]> wrote:

> Andre Reitz wrote:
> 
> > 
> > We have a big problem,
> > 
> > We have a client-server Application running on sapdb with
> > a multithreaded python server as a middleware.
> > 
> > This means: one Multithreaded program which has several
> > connections on the database (all under the same database user 
> > account).
> > 
> > 
> > Our Problem: 
> > 
> > - Sometimes the System blocks
> > 
> > The possible causes: (we think so)
> > 
> > - We forgot a "commit" in our application 
> > - Sapdb runs out of free locks or any other resources
> > 
> > Our Questions:
> > 
> > - Is Isolation Level 1 (or 10) the default of the python driver?
> > - Do selected rows also get locked in Isolation Level 1?
> 
> Usually they are not locked. But there exist kernel-versions 
> in which a row is selected, but updated by another transaction.
> It then has to wait for the release of that update/insert/delete-lock, i.e.
> has to wait for the commit/rollback of the other transaction.
> Then it will have a lock afterwards.
> 

Is this a bug or a feature. (We are using sapdb 7.3.0.29)
It sounds like it is a bug, isn`t it?

> > - If they get locked, is there a limit (maximum of row locks) 
> 
> 
> YES, the installation parameter MAXLOCKS, (default:2500)
> 
> 
> > which can lead
> >   to the blocking because the system runs out of resources 
> > (or something similar)?
> > (in other words:)
> 
> No, should not block, should return an error
> 
> Please check the output of the systemtable LOCKS in
> the case of blocking database.
> 
> And please check the value of the parameter
> REQUEST_TIMEOUT.
> 
> 
> > - Our applications sends many many selects without a 
> > following commit/rollback.
> >   Only when data is inserted/updated/deleted, the clients 
> > send a commit/rollback.
> >   Is it possible that the selects will lead to a deadlock?
> 
> 
> Possible: yes
> 

The same question, bug or feature?


> Elke
> SAP Labs Berlin
> 
> > 
> > - What about the parameter DEADLOCK_DETECTION (my value currently: 4)?
> >   does it use very much resources if i set it to a higher value?
> >   does it make sense to set it highter?
> > 
> > 
> > 
> > Thank you very much in advance,
> > Greetings and best regards, Andre'
> > 
> > -- 
> > _____________________________________________
> > inworks GmbH            Andre Reitz         
> > H�rvelsinger Weg 39     Tel. 0731/93 80 7-21
> > 89081 Ulm               http://www.inworks.de
> > 
> > _______________________________________________
> > sapdb.general mailing list
> > [EMAIL PROTECTED]
> > http://listserv.sap.com/mailman/listinfo/sapdb.general
> > 



Thank you very much in advance,

Best regards, Andre'


-- 
_____________________________________________
inworks GmbH            Andre Reitz             
H�rvelsinger Weg 39     Tel. 0731/93 80 7-21
89081 Ulm               http://www.inworks.de

_______________________________________________
sapdb.general mailing list
[EMAIL PROTECTED]
http://listserv.sap.com/mailman/listinfo/sapdb.general

Reply via email to