Re: Re: Has anyone done any scalability work on dbms_lock?

nuno-- what level are you trying to scale it to? how long will you hold the locks? I used it last year because only one process could run at a time.

seemed to have similiar over head to 'select for update'. If you look at the PL/SQL Packages book by Fuerstein et al(not a real popular book, but I like it)... there is a nifty wrapper for DBMS_LOCK. I based my code off of that.

>
> From: "Carel-Jan Engel" <cjpengel.dbalert_at_xs4all.nl>
> Date: 2004/01/21 Wed AM 08:24:25 EST
> To: Multiple recipients of list ORACLE-L <ORACLE-L_at_fatcity.com>
> Subject: Re: Has anyone done any scalability work on dbms_lock?
>
> > As in: does it present an inherent or hidden performance
> > problem when a lot of sessions try to lock/release the same
> > lock?
> Will serialize perfectly!
>
> > Or how many lock/release per second. Or some other
> > idea of how efficient it is?
> Depends on the work done between acquiring the lock and releasing it.
>
> >
> > Need to use it in a design, but not sure of any potential
> > performance hits or scalability issues. Any ideas?
> When sessions acquire the same lock (as asked), only one session can do
> the work in a given moment. So, it doesn't scale. There will be overhead,
> but that also is relative to the duration of the work done while the lock
> is held.
>
> Maybe AQ can help, by doing the work asynchronously in the background and
> so lift the serialization from the primary proces(ses)?
>
>
> Regards, Carel-Jan
>
> ===
> If you think education is expensive, try ignorance. (Derek Bok)
> ===
>
> >
> > TIA.
> > Cheers
> > Nuno Souto
> > nsouto_at_optusnet.com.au
> > --
> > Please see the official ORACLE-L FAQ: http://www.orafaq.net
> > --
> > Author: Nuno Souto
> > INET: nsouto_at_optusnet.com.au
> >
> > Fat City Network Services -- 858-538-5051 http://www.fatcity.com
> > San Diego, California -- Mailing list and web hosting services
> > ---------------------------------------------------------------------
> > To REMOVE yourself from this mailing list, send an E-Mail message
> > to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
> > the message BODY, include a line containing: UNSUB ORACLE-L
> > (or the name of mailing list you want to be removed from). You may
> > also send the HELP command for other information (like subscribing).
> >
>
>
>
>
> --
> Please see the official ORACLE-L FAQ: http://www.orafaq.net
> --
> Author: Carel-Jan Engel
> INET: cjpengel.dbalert_at_xs4all.nl
>
> Fat City Network Services -- 858-538-5051 http://www.fatcity.com
> San Diego, California -- Mailing list and web hosting services
> ---------------------------------------------------------------------
> To REMOVE yourself from this mailing list, send an E-Mail message
> to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
> the message BODY, include a line containing: UNSUB ORACLE-L
> (or the name of mailing list you want to be removed from). You may
> also send the HELP command for other information (like subscribing).
>

-- 
Please see the official ORACLE-L FAQ: http://www.orafaq.net
-- 
Author: <ryan.gaffuri_at_cox.net
  INET: ryan.gaffuri_at_cox.net

Fat City Network Services    -- 858-538-5051 http://www.fatcity.com
San Diego, California        -- Mailing list and web hosting services
---------------------------------------------------------------------
To REMOVE yourself from this mailing list, send an E-Mail message
to: ListGuru_at_fatcity.com (note EXACT spelling of 'ListGuru') and in
the message BODY, include a line containing: UNSUB ORACLE-L
(or the name of mailing list you want to be removed from).  You may
also send the HELP command for other information (like subscribing).