Hello All,

I had sent a mail regarding this slony deadlock. We have seen one more issue while doing a subscribe.
Can one of you please let me know what might be the issue ? We are deploying shortly and need some information.
Below is the error we got. This is the second time:

<stdin>:18: PGRES_FATAL_ERROR select "_evslonycluster".subscribeSet(1, 1, 2,
't');  - ERROR:  deadlock detected
DETAIL:  Process 17442 waits for ExclusiveLock on relation 17494 of database
16385; blocked by process 17433.
Process 17433 waits for ExclusiveLock on relation 17494 of database 16385;
blocked by process 17442.
CONTEXT:  SQL statement "LOCK TABLE _evslonycluster.sl_event IN EXCLUSIVE MODE;
INSERT INTO _evslonycluster.sl_event (ev_origin, ev_seqno, ev_timestamp,
ev_snapshot, ev_type, ev_data1, ev_data2, ev_data3, ev_data4, ev_data5,
ev_data6, ev_data7, ev_data8) VALUES ('1',
nextval('_evslonycluster.sl_event_seq'), now(),
"pg_catalog".txid_current_snapshot(), $1, $2, $3, $4, $5, $6, $7, $8, $9);
SELECT currval('_evslonycluster.sl_event_seq');"
PL/pgSQL function "subscribeset" line 56 at assignment


The the first time we got the error, the mail is below.

Please Help.

Thanks.


-----Original Message-----
From: Nagaraja, Madhukar (Madhukar)
Sent: Thursday, September 03, 2009 3:51 PM
To: slony1-general at lists.slony.info
Subject: Slony caused a Deadlock after a switchover.

Hello,
We have been using the slony for the past few months. We are still in dev/test cycle and not yet gone to production. But recently we did a switchover operation and we got this error in the slony logs. Can you help us out in this ?? Please let me know if you need any more information. We are using slony1 2.0.1.

This is the error we got:

<stdin>:5: PGRES_FATAL_ERROR select "_evslonycluster".lockSet(1); select pg_catalog.txid_snapshot_xmax(pg_catalog.txid_current_snapshot()); - ERROR:  deadlock detected

DETAIL:  Process 12169 waits for AccessExclusiveLock on relation 17591 of database 16386; blocked by process 1987.

Process 1987 waits for AccessShareLock on relation 17480 of database 16386; blocked by process 12169.

CONTEXT:  SQL statement "create trigger "_evslonycluster_lockedset" before insert or update or delete on "public"."domaincontrollerinfo" for each row execute procedure

                                "_evslonycluster".lockedSet ('_evslonycluster');"

PL/pgSQL function "lockset" line 44 at EXECUTE statement

Thanks.