Oracle FAQ | Your Portal to the Oracle Knowledge Grid |
![]() |
![]() |
Home -> Community -> Mailing Lists -> Oracle-L -> Re: RE: difference between child and parent latches?
thanks for your help. I want to drill a little deeper.
>
> From: K Gopalakrishnan <kaygopal_at_yahoo.com>
> Date: 2004/03/23 Tue AM 07:57:34 EST
> To: oracle-l_at_freelists.org
> Subject: Re: RE: difference between child and parent latches?
>
> Ryan:
>
> My understanding is whenever/whereever,
>
> a)single latch is not sufficiant to protect the entire data structure
> b)the contention for that particular latch is severe and the structure
> can be logically split in to multiple data structures
>
> multiple latches are implemented and grouped as parent-child
> relationships.
>
> So to answer your question, both are essentially same, but the child
> latches are created during instance startup (parents are defined in the
> code) and the number of children can be controlled by some underscore
> parameters.
>
> Hope this answers your question ! if not Ask Steve Adams
>
> Regards,
> Gopal
>
>
>
> --- ryan.gaffuri_at_cox.net wrote:
> > i'm still having trouble understanding what the real difference is
> > between a parent latch and a child latch?
> > >
> > > From: K Gopalakrishnan <kaygopal_at_yahoo.com>
> > > Date: 2004/03/23 Tue AM 04:28:38 EST
> > > To: oracle-l_at_freelists.org
> > > Subject: RE: difference between child and parent latches?
> > >
> > > Paul:
> > >
> > > You will have only one latch if your shared pool is less than 250
> > MB.
> > > But the v$latch_children may (probably) have 7 entries, but only
> > one
> > > latch will be protecting the shared pool structures. This can be
> > > verified by checking the misses/sleeps for that particular child.
> > >
> > > Regards,
> > > Gopal
> > >
>
> ----------------------------------------------------------------
> Please see the official ORACLE-L FAQ: http://www.orafaq.com
> ----------------------------------------------------------------
> To unsubscribe send email to: oracle-l-request_at_freelists.org
> put 'unsubscribe' in the subject line.
> --
> Archives are at http://www.freelists.org/archives/oracle-l/
> FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html
> -----------------------------------------------------------------
>
-- Archives are at http://www.freelists.org/archives/oracle-l/ FAQ is at http://www.freelists.org/help/fom-serve/cache/1.html -----------------------------------------------------------------Received on Tue Mar 23 2004 - 08:22:42 CST
![]() |
![]() |