what is Reads and Writes in Sys.dm_exec_requests DMV of SQL Server

As per explaination given on MSDN at link http://msdn.microsoft.com/en-us/library/ms177648.aspx I am not able to understand the meaning of Reads and Writes开发者_运维问答 fully.whether it is physical or logical or database Reads and Writes. Please help me out in this regards

It's number of physical reads/writes of 8k blocks. So if you multiply it by 8 you will get number of kilobytes that was read/written.

Martin answered your question...the logical_reads column corresponds to logical reads (i.e. requests that can be fulfilled by data currently available in the buffer cache) while reads corresponds to physical reads (i.e. requests for data that isn't currently in the buffer cache and requires a read from the relevant data file on disk).

A write in SQL Server modifies the page in memory; modified pages are marked as dirty and written to disk by asynchronous processes (also what Martin said).

Just to add, all of these figures represent number of pages, not rows.