Len Walter wrote:

>G'day ,
>
>My environment is postgres 7.4.8 / Slony 1.1.0 / RHEL4ES on x86.
>
>I've got a three-or-four month old slony cluster which currently has a
>large sl_log_1 table:
>db=# select count(*) from _slony.sl_log_1;
>  count
>---------
> 1031377
>(1 row)
>
>I've run the step at http://cbbrowne.com/info/faq.html#AEN42511 and
>deleted a few old entries from sl_confirm, then waited for the cleanup
>thread to purge the log table, as well as running the task manually.
>
>The FAQ says (in the same entry) "each cleanupEvent run .... is the
>event in which old data is purged from sl_log_1 and sl_seqlog".
>However, I've looked at the function as installed in the slony schema
>and it doesn't do that, as far as I can tell. (attached below)
>
>Can anyone give me a pointer to finding where this task does get run?
>  
>
The trouble here is that "cleanupEvent" is overloaded.  There are two
things by that name:

1.  There is a pl/pgsql function, cleanupEvent(), in
src/backend/slony1_funcs.sql, which is strictly about cleaning out events

2.  There is a C function, cleanupEvent_main(), in
src/slon/cleanup_thread.c, which runs the pl/pgsql function *as well as*
doing other things that notably includes purging data from sl_log_1.

You might look at the queries in src/slon/cleanup_thread.c to see what
it is doing.

The query most likely to be useful is the following...

                     "select ev_origin, ev_seqno, ev_minxid "
                     "from %s.sl_event "
                     "where (ev_origin, ev_seqno) in "
                     "    (select ev_origin, min(ev_seqno) "
                     "     from %s.sl_event "
                     "     where ev_type = 'SYNC' "
                     "     group by ev_origin); ",

If confirmations haven't made it back from some node, that would block
deletions from taking place...

In the past, the following query used to be useful; it ought to be
obsolete in 1.1...

select * from _oxrsbar.sl_confirm where con_origin not in (select no_id
from _oxrsbar.sl_node) or con_received not in (select no_id from
_oxrsbar.sl_node)