Title
#users-public
t

Tihomir Dimov

03/31/2022, 2:57 PM
Hi 👋 I am getting error while dropping a partition. My table has daily partitions and a websocket is saving data all the time in the table. When I run:
ALTER TABLE test_table DROP PARTITION LIST '2022-03-28';
I am getting the following error:
Could not publish writer ALTER TABLE task [table=test_table]ALTER TABLE test_table DROP PARTITION LIST '2022-03-28';
Error from logs:
2022-03-31T14:33:37.947461Z E i.q.c.CairoEngine could not publish writer task [table=test_table,instance42,seqCursor=-1]
The strange thing is that dropping partition from this table worked ~20 times in the past days. Any ideas how to fix it?
Vlad

Vlad

03/31/2022, 3:17 PM
hey Tihomir, this is a bug that is fixed in 6.3(next release). The workaround is restart for now 😞
Alex Pelagenko

Alex Pelagenko

03/31/2022, 3:20 PM
You can push the limit of ALTERs before a restart is needed in server.conf as a workaround before the fix released.
3:22 PM
cairo.writer.command.queue.capacity=1024
if you add this line, the limit will go from 32 to 1024
t

Tihomir Dimov

03/31/2022, 3:39 PM
Thanks for the fast answers. It is now working. Should I remove the
cairo.writer.command.queue.capacity=1024
after the update to 6.3?
Vlad

Vlad

03/31/2022, 3:43 PM
yeah, this is going to be too much. 6.3 will have multiple queues, one per writer. This value should be set quite low. Perhaps 8. Best is to remove this setting in the future
t

Tihomir Dimov

03/31/2022, 3:50 PM
Okay, thanks🤝