Source filters, now everywhere
Demo by @pulpdrewBetter AI-generated dashboards for custom schemas
Demo by @pulpdrewSimpler hashing for OTel metrics, and a primary key idea
Demo by @dhablecityHash64, while Map-based schemas first concatenated three maps before hashing. It turns out that extra work wasn’t needed. Both schema types now use the same cityHash64 implementation, simplifying the code and avoiding unnecessary map allocations during hashing.
The work also highlighted a potential optimization for the OpenTelemetry metrics schema. Today, the primary key stores the full attributes map, which increases memory usage because ClickHouse keeps the map in memory as part of the index. One idea is to materialize an attribute hash at insert time and use that in the primary key instead. Nothing has changed yet, but with OpenTelemetry schema updates now back on the table, it’s an optimization worth revisiting.
Related PRs: #2475 Unify AttributesHash to variadic cityHash64