Hello!

We use slony 2.1.4 and will be forced to this version for some more time.

Today I debugged an issue where the logswitching did not finish.
Although it would be safe (in my opinion) to truncate the old log table,
the logswitch_finish() fails with:

  could not lock sl_log_2 - sl_log_2 not truncated

The function tries to lock the sl_log table with:

 begin;
 lock table "_regdnscluster".sl_log_2 in access exclusive mode nowait;

The problem seems, that the table is so hot in reading (55 slaves) that
the lock hardly succeeds.

If I call logswitch_finish() manually (because the cleanup thread tries
only every 10 minutes - hard coded) I need to call it approx 100 times
until I get the lock.

Is there a reason to use "nowait"? As far as I understand, it should be
safe to wait some time until giving up, i.e.:

SET lock_timeout TO '10s';
begin;
lock table "_regdnscluster".sl_log_2 in access exclusive mode;


This way, log switching can happen more often.

Thanks
Klaus