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Home -> Community -> Usenet -> c.d.o.server -> help on distributed locks?
We've been running our database application (Oracle 8.1.5 on NT) just fine for a couple weeks now.
Suprisingly, we noticed the application come to a halt over the weekend and remain in this idle state ever since (3 days so far).
The application is calling pl/sql stored procedures that move data from one oracle instance to another oracle instance via a dblink.
In the pl/sql code of each procedure, I catch exceptions that any of the procedures throw and write them out to an error log table. I found this error in the log:
Cause: Exceeded INIT.ORA DISTRIBUTED_LOCK_TIMEOUT seconds waiting for lock.
Action: Treat as a deadlock.
Huh? Come again? What?
All the procedures have explicit commits in them at very frequent intervals. There are no errors about failure to extend rollback segments etc... I'm at a loss here as to what is being locked.
Additionally, Oracle's documentation says to treat this as a deadlock, however internally oracle does not do the same as my udump folder is empty (on both instances).
I'm pretty sure that bouncing the databases will alleviate the situation(This is a dev environment) but I don't want to do that until I figure out what happened here.
First of all, I don't know what exactly is locked. I checked the v$locked_object table on both instances and it was completely empty. However the V$lock table did show some exclusive and row locks being held by certain sessions. (I don't know what objects those sessions are locking )
Additionally, when I try to update the code of one of my stored procedures (via "create or replace procedure...") I keep getting the following error:
ORA-04021:timeout occurred while waiting to lock object
So I know that my procedure is locked (I assume this puppy is running...but is in some kind of wait state...probably waiting on some other locked resource). I suspect other things are locked as well since the first thing each procedure does is insert a row into a log_table that contains the sysdate and "starting"...This table has no new records for the past three days (when the problem started happening)...However our application calls the procedures and it shows them as running...but they all seem to be in some strange wait state as they have been running for 3 days now whereas prior to 3 days ago they would usually complete in under 10 seconds.
The log table itself is not locked as I can insert and update it fine.
Does anyone have a clue what might be happening? Any way to find out the object that is locked and perhaps the statement that was issued that caused the lock?
Or is there something else going on here? Specifically in regards to distributed transactions. At the least, I'm hoping someone can at least point me in the right direction?
Thanks in advance,
Gavin
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Received on Mon Jul 31 2000 - 00:00:00 CDT
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