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Here is the problem that you *could* be facing:
Infact I just had the same scenario at a customer site. They complained about 'hanging locks' (some process would hold on too locks for a long time and others would wait very long). So they assumed a locking problem. The locking problem in their case was a symptom of not having enough DBWRs.
So what to do in your case:
Anjo.
James Mu wrote:
> hi,
> You ask a big question. To let it some clear, I think you should record
> the ora number, then go to metalink to query some info.
> James
>
> Maurice Samuels <samuels_at_red.seas.upenn.edu> wrote in message
> news:9crsph$o3r$1_at_netnews.upenn.edu...
> > hi,
> > recently i turned on multiple dbwr's (4) and increased the
db_block_lru_latches (24) on an 8-CPU Sun 5500
> > server with 8G of memory (oracle 8.0.x). a few times when i've tried to
run 5 insert /*+append ..
> > operations, i get
> > deadlock messages written to the alert.log and some of the operations
outright fail. but i have no problems
> > running 4 of those types of operations at a time (is this related to how
many writer's there are).
> > had anyone ever run into anything like this?
> > what performance views should i be watching to see how oracle is managing
the buffer cache and locks?
> > can anyone point to a good book on the topic of multiple dbwr's and locks?
> > the oracle documentation regarding the multiple dbwr's is a bit confusing
on this topic.
> > thanks in advance
> > -maurice
> > samuels_at_seas.upenn.edu
Received on Tue May 08 2001 - 02:21:57 CDT