Hi Sometimes simple sql's like this takes a very long time "select count(*) from information_schema.tables;"
Other sql's not including system tables may work ok but login also takes a very long time. The CPU load on the server is around 25%. There is no iowait. This happens typically when we are running many functions in parallel creating many temp tables and unlogged tables I think. Here is a slow one: https://explain.depesz.com/s/tUt5 and here is fast one : https://explain.depesz.com/s/yYG4 Here are my settings (the server has around 256 GB og memory) : max_connections = 500 work_mem = 20MB effective_cache_size = 96GB effective_io_concurrency = 256 shared_buffers = 96GB temp_buffers = 80MB Any hints ? Thanks . Lars
