Since 2008 has been developing data storage systems for Yandex Metrica. ClickHouse project founder and developer.
Presentation: Performance Analysis of ClickHouse Queries”
“What to do if your query is not running fast enough? Where to look to determine, does the query use computational resources in optimal manner, or there is a chance for speedup?
In my talk, I will cover both the built-in capabilities of query performance introspection in ClickHouse and the features provided by the operating system that everyone should know. Several examples from practice will be given – in some cases, queries can be easily accelerated by changing the settings, while others required serious improvements in the ClickHouse code.”