Top 50 queries by total blocks (buffers)

top_50_by_blocks.sql

SELECT shared_blks_hit + shared_blks_read + shared_blks_dirtied + shared_blks_written + local_blks_hit + local_blks_read + local_blks_dirtied + local_blks_written + temp_blks_read + temp_blks_written as total_blocks
      ,(total_exec_time + total_plan_time)::int as total_time
      ,calls
      ,query
FROM pg_stat_statements
ORDER BY 1 DESC
LIMIT 50;