Re: logical replication - negative bitmapset member not allowed

Hello,

On Thu, 4 Apr 2019 23:37:04 +0200
Peter Eisentraut <peter(dot)eisentraut(at)2ndquadrant(dot)com> wrote:

> On 2019-04-01 23:43, Alvaro Herrera wrote:
> > Maybe the replica identity of a table got set to a unique index on oid?
> > Or something else involving system columns? (If replication is
> > otherwise working, the I suppose there's a separate publication that's
> > having the error; the first thing to isolate would be to see what tables
> > are involved in that publication).
>
> Looking through the code, the bms_add_member() call in
> logicalrep_read_attrs() does not use the usual
> FirstLowInvalidHeapAttributeNumber offset, so that seems like a possible
> problem.
>
> However, I can't quite reproduce this. There are various other checks
> that prevent this scenario, but it's plausible that with a bit of
> whacking around you could hit this error message.

Here is a script to reproduce it under version 10, 11 and 12:

################################################
# env
PUB=/tmp/pub
SUB=/tmp/sub
unset PGPORT PGHOST PGDATABASE PGDATA
export PGUSER=postgres

# cleanup
kill %1
pg_ctl -w -s -D "$PUB" -m immediate stop; echo $?
pg_ctl -w -s -D "$SUB" -m immediate stop; echo $?
rm -r "$PUB" "$SUB"

# cluster
initdb -U postgres -N "$PUB" &>/dev/null; echo $?
initdb -U postgres -N "$SUB" &>/dev/null; echo $?
echo "wal_level=logical" >> "$PUB"/postgresql.conf
echo "port=5433" >> "$SUB"/postgresql.conf
pg_ctl -w -s -D $PUB -l "$PUB"-"$(date +%FT%T)".log start; echo $?
pg_ctl -w -s -D $SUB -l "$SUB"-"$(date +%FT%T)".log start; echo $?
pgbench -p 5432 -qi
pg_dump -p 5432 -s | psql -qXp 5433

# fake activity
pgbench -p 5432 -T 300 -c 2 &

# replication setup
psql -p 5432 -Xc "CREATE PUBLICATION prov FOR ALL TABLES"
psql -p 5433 -Xc "CREATE SUBSCRIPTION sub
CONNECTION 'port=5432'
PUBLICATION prov"

# wait for the streaming
unset V;
while [ "$V" != "streaming" ]; do sleep 1
V=$(psql -AtXc "SELECT 'streaming'
FROM pg_stat_replication WHERE state='streaming'")
done

# trigger the error message
psql -p 5433 -Xc "ALTER SUBSCRIPTION sub DISABLE"
psql -p 5433 -Xc "ALTER TABLE pgbench_history ADD id SERIAL PRIMARY KEY"
psql -p 5432 -Xc "ALTER TABLE pgbench_history ADD id SERIAL PRIMARY KEY"
psql -p 5433 -Xc "ALTER SUBSCRIPTION sub ENABLE"
################################################

Regards,