Wondering how long it takes to change the retention for trac

Question

Wondering how long it takes to change the retention for traces usually through the UI Its seemingly taking minutes at the moment to go from 6 hours to 2 days Any idea why it would take so long I would assume it wouldn t be proportional to the amount of data

Alexei Zenin · Answer

metrics took a minute or 2 but traces still seems to keep going

Alexei Zenin · Answer

currently there are 18 million spans stored ~20 GB

Alexei Zenin · Answer

seems it worked now Took like 10 minutes wonder if this can be optimized as it seems it scales with the amount of data

Alexei Zenin · Answer

cc < Prashant Shahi> < Pranay>

Pranay · Answer

Yeah sometimes it takes more time < Vishal Sharma> may have more insights on this

Vishal Sharma · Answer

< Alexei Zenin> Traces has around 5 6 tables and far more data than metrics Setting TTL on clickhouse tables with large is very slow that s why we are using async api for setting TTL For new users it is recommended to set TTL while data is less

Alexei Zenin · Answer

I see Can this be optimized at all I foresee a future where I will have TB of data in Clickhouse and will need to tweak the TTL Will it take days or weeks to change at that point I would assume I wouldn t have to wipe out all data for the past month causing our team to lose data and start from scratch each time Is this possible to optimize at all

Vishal Sharma · Answer

< Alexei Zenin> Clickhouse team is already working improving on optimizing TTL Meanwhile we will search other ways to drop old data You can track issue here