Hi.

I found a bug , unexpected slon shutdown when dropping node.

-PostgreSQL 8.1.2
-Slony-I 1.1.5
--perltools was not used.
-RHEL4 update2

TO REPRODUCE THIS BUG:

1. make sure PostgreSQL 8.1,pgbench and Slony-I was installed.

2. Execute add.sh follows. It will create 1 master and 2-slave cluster
named "nodetest". node 1-2 and 1-3 path exists.

[tanida at srapc2209 sl]$ cat add.sh
#!/bin/sh
CLUSTERNAME=nodetest

RUSER=postgres
killall slon
dropdb node1
dropdb node2
dropdb node3
createdb node1
createdb node2
createdb node3
createlang plpgsql node1
pgbench -i -s 1 node1
pg_dump -s node1 | psql node2
pg_dump -s node1 | psql node3
slonik <<_EOF_
cluster name = $CLUSTERNAME;
node 1 admin conninfo = 'dbname=node1';
node 2 admin conninfo = 'dbname=node2';
node 3 admin conninfo = 'dbname=node3';
init cluster ( id=1, comment = 'Master');
create set (id=1, origin=1, comment='All tables');
table add key (node id = 1, fully qualified name = 'public.history');
store node (id=2, comment = 'Slave');
store node (id=3, comment = 'Slave');
store path (server = 1, client = 2, conninfo='dbname=node1 ');
store path (server = 2, client = 1, conninfo='dbname=node2 ');
store path (server = 1, client = 3, conninfo='dbname=node1 ');
store path (server = 3, client = 1, conninfo='dbname=node3 ');

store listen (origin=1, provider = 1, receiver =2);
store listen (origin=2, provider = 2, receiver =1);
store listen (origin=1, provider = 1, receiver =3);
store listen (origin=2, provider = 1, receiver =3);
store listen (origin=3, provider = 3, receiver =1);
store listen (origin=3, provider = 1, receiver =2);
set add table (set id=1, origin=1, id=1, fully qualified name = 'public.accounts', comment='accounts table');
set add table (set id=1, origin=1, id=2, fully qualified name = 'public.branches', comment='branches table');
set add table (set id=1, origin=1, id=3, fully qualified name = 'public.tellers', comment='tellers table');
set add table (set id=1, origin=1, id=4, fully qualified name = 'public.history', comment='history table', key = serial);
#wait for event(origin=all,confirmed=all);
_EOF_
slon nodetest "dbname=node1" >node1.log 2>&1 &
slon nodetest "dbname=node2" >node2.log 2>&1 &
slon nodetest "dbname=node3" >node3.log 2>&1 &
slonik <<_EOF_
cluster name = $CLUSTERNAME;
node 1 admin conninfo = 'dbname=node1';
node 2 admin conninfo = 'dbname=node2';
node 3 admin conninfo = 'dbname=node3';
subscribe set ( id = 1, provider = 1, receiver = 2, forward = yes);
subscribe set ( id = 1, provider = 1, receiver = 3, forward = yes);
_EOF_

3. Execute del.sh follows. It will drop node 3.

[tanida at srapc2209 sl]$ cat del.sh
#!/bin/sh
CLUSTERNAME=nodetest

slonik <<_EOF_
cluster name = $CLUSTERNAME;
node 1 admin conninfo = 'dbname=node1';
node 2 admin conninfo = 'dbname=node2';
node 3 admin conninfo = 'dbname=node3';
drop node (id=3);
_EOF_

4. slon for node3 will shutdown immediately , but after 20 seconds ,
slon for node1 will shutdown , which must be restart.

log of node1 shows:

2006-03-08 20:24:11 JST INFO   localListenThread: got restart notification - signal scheduler
2006-03-08 20:24:11 JST DEBUG1 slon: restart requested
2006-03-08 20:24:11 JST DEBUG1 cleanupThread: thread done
2006-03-08 20:24:11 JST DEBUG1 syncThread: thread done
2006-03-08 20:24:11 JST DEBUG1 main: scheduler mainloop returned
2006-03-08 20:24:11 JST DEBUG1 localListenThread: thread done
2006-03-08 20:24:31 JST WARN   main: shutdown timeout exiting
2006-03-08 20:24:31 JST DEBUG1 slon: shutdown now requested

It seems something unconditional happened in remoteListenThread or
remoteWorkerThread and deadlocked , so wait 20 seconds and shutdowned by
timeout.

This example is for "drop node", but It will occurs other statement
requests restarts , such as "uninstall node" , "move set" or "failover".


-- 
TANIDA Yutaka <tanida at sraoss.co.jp>