Huge "Network I/O" type resource waits
Stop using Activity Monitor
Use sp_WhoIsActive to figure out what's actually going on


It could be backups, in which case there's not a whole heck of a lot you can do that doesn't involve hardware upgrades (maybe that 1 Gb iSCSI wasn't such a great idea...)

It could be client-side code consuming data RBAR (think foreach loops for every row coming in), or asking for a lot of rows all at once (this is where paging queries can help).

It could be something else entirely!

To get an idea what your server is waiting on the most, head over to firstresponderkit.org -- full disclosure, I contribute to this open source project -- and grab sp_BlitzFirst (or, heck, grab'em all).

You can run this command to look at your wait stats as a whole, since startup.

EXEC sp_BlitzFirst @SinceStartup = 1 

Or this to get a sample of wait stats during a slowdown.

EXEC sp_BlitzFirst @Seconds = 30, @ExpertMode = 1 

Hope this helps!