Clean pages can be fl ushed from cache using dbcc dropcleanbuffers, which can be handy when you’re troubleshooting development and test environments because it forces subsequent reads to be fulfi lled from disk, rather than cache, but doesn’t touch any dirty pages.
You can use the following query, which is based on the sys.dm_os_buffer_descriptors DMV, to see how many dirty pages exist in each database:
SELECT db_name(database_id) AS 'Database',count(page_id) AS 'Dirty Pages'
WHERE is_modified =1
GROUP BY db_name(database_id)
ORDER BY count(page_id) DESC