Inquiry Regarding the Method to Initialize system.backup_actions

[kisoongjang]

When there are many rows in system.backup_actions, errors occur during API calls.
If there is a method to initialize this through clickhouse-backup cli please share it

Thanks

[Slach]

how many actions do you have exactly? we tested it on 10k rows and all works fine
and which errors exactly do you see?

we have a plan about store only last X actions and add some persistence
#941
but this is low priority task

[kisoongjang]

I called the list periodically to monitor whether the backup was done well through Grafana,
resulting in many rows being saved.

[Slach]

which clickhouse-backup version do you use?
how often did you call /backup/list (SELECT * FROM system.backup_list)?
why not use SELECT * FROM system.backup_actions (GET /backup/status or GET /backup/actions) ?

You can restart clickhouse-backup in this case

[Dima-chj]

when the clickhouse parameter max_read_buffer_size = 1000000
I got below errors and backup failed.
After change the value to 3000000, backup process succeeded.
Are there any way to clean up table backup_actions?

Code: 26. DB::Exception: Received from chi-signoz-clickhouse-cluster-0-0:9000. DB::Exception: Cannot parse JSON string: expected opening quote: (while reading the value of key command): (at row 10490) : (in file/uri http://127.0.0.1:7171/backup/actions): While executing ParallelParsingBlockInputFormat: While executing URL. (CANNOT_PARSE_QUOTED_STRING) (query: SELECT status,error FROM system.backup_actions WHERE command='create chi-signoz-clickhouse-cluster-0-0-increment-2025-03-26-15-00-00')

[Slach]

ok. got it, currently only one way restart of clickhouse-backup

could you suggest, what is your backup pattern? how did you run thousands backup actions?

could you share SELECT count() FROM system.backup_actions ?

[Dima-chj]

Thanks. I made alarm in Grafana with term that backup file count > 20 (shard count)
That's why there are so many actions... 1 select per minute..
I turned off the alarm now.

[Slach]

clickhouse-backup provide prometheus compatible endpoint with :7171/metrics, you can use it and get relevant metrics