synapse_port_db fails on re-run with complaints about postgres sequences

[richvdh]

if an initial run of synapse_port_db fails for any reason during data import, a subsequent attempt to re-run it fails with:

2020-11-12 18:09:46,970 - synapse.storage.util.sequence - 132 - WARNING - Postgres sequence events_stream_seq is behind table events: 1 < 127
2020-11-12 18:09:46,973 - synapse_port_db - 643 - ERROR - 
Traceback (most recent call last):
  File "/home/rav/work/synapse/scripts/synapse_port_db", line 550, in run
    self.hs_config.get_single_database()
  File "/home/rav/work/synapse/scripts/synapse_port_db", line 499, in build_db_store
    store = Store(DatabasePool(hs, db_config, engine), db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/client_ips.py", line 34, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/deviceinbox.py", line 286, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/devices.py", line 879, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/events_bg_updates.py", line 32, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/media_repository.py", line 27, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/registration.py", line 932, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/registration.py", line 74, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/cache.py", line 43, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/room.py", line 961, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/roommember.py", line 820, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/search.py", line 92, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/state/bg_updates.py", line 184, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/state.py", line 323, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/roommember.py", line 55, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/events_worker.py", line 103, in __init__
    writers=hs.config.worker.writers.events,
  File "/home/rav/work/synapse/synapse/storage/util/id_generators.py", line 264, in __init__
    db_conn, table=table, id_column=id_column, positive=positive
  File "/home/rav/work/synapse/synapse/storage/util/sequence.py", line 136, in check_consistency
    % {"seq": self._sequence_name, "table": table, "max_id_sql": table_sql}
synapse.storage.engines._base.IncorrectDatabaseSetup: 
Postgres sequence 'events_stream_seq' is inconsistent with associated
table 'events'. This can happen if Synapse has been downgraded and
then upgraded again, or due to a bad migration.

To fix this error, shut down Synapse (including any and all workers)
and run the following SQL:

    SELECT setval('events_stream_seq', (
        SELECT GREATEST(MAX(stream_ordering), 0) FROM events
    ));

See docs/postgres.md for more information.

Traceback (most recent call last):
  File "/home/rav/work/synapse/scripts/synapse_port_db", line 550, in run
    self.hs_config.get_single_database()
  File "/home/rav/work/synapse/scripts/synapse_port_db", line 499, in build_db_store
    store = Store(DatabasePool(hs, db_config, engine), db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/client_ips.py", line 34, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/deviceinbox.py", line 286, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/devices.py", line 879, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/events_bg_updates.py", line 32, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/media_repository.py", line 27, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/registration.py", line 932, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/registration.py", line 74, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/cache.py", line 43, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/room.py", line 961, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/roommember.py", line 820, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/search.py", line 92, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/state/bg_updates.py", line 184, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/state.py", line 323, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/roommember.py", line 55, in __init__
    super().__init__(database, db_conn, hs)
  File "/home/rav/work/synapse/synapse/storage/databases/main/events_worker.py", line 103, in __init__
    writers=hs.config.worker.writers.events,
  File "/home/rav/work/synapse/synapse/storage/util/id_generators.py", line 264, in __init__
    db_conn, table=table, id_column=id_column, positive=positive
  File "/home/rav/work/synapse/synapse/storage/util/sequence.py", line 136, in check_consistency
    % {"seq": self._sequence_name, "table": table, "max_id_sql": table_sql}
synapse.storage.engines._base.IncorrectDatabaseSetup: 
Postgres sequence 'events_stream_seq' is inconsistent with associated
table 'events'. This can happen if Synapse has been downgraded and
then upgraded again, or due to a bad migration.

To fix this error, shut down Synapse (including any and all workers)
and run the following SQL:

    SELECT setval('events_stream_seq', (
        SELECT GREATEST(MAX(stream_ordering), 0) FROM events
    ));

See docs/postgres.md for more information.


Postgres sequence 'events_stream_seq' is inconsistent with associated
table 'events'. This can happen if Synapse has been downgraded and
then upgraded again, or due to a bad migration.

To fix this error, shut down Synapse (including any and all workers)
and run the following SQL:

    SELECT setval('events_stream_seq', (
        SELECT GREATEST(MAX(stream_ordering), 0) FROM events
    ));

See docs/postgres.md for more information.

(yes, it prints the stacktrace twice and the error message three times.)

It seems like synapse_port_db shouldn't be running the checks on the sequence generators?

[richvdh]

oh I think this is a dup of #8619