Generally, your goal is to configure caches in proportion to the number of times that the pages in the caches will be accessed by your queries and to configure pools within caches in proportion to the number of pages used by queries that choose I/O of that pool’s size.
If your databases and their logs are on separate logical devices, you can estimate cache proportions using sp_sysmon or operating system commands to examine physical I/O by device.
See “Disk I/O management” on page 102 in the book Performance and Tuning: Monitoring and Analyzing for Performance for information about the sp_sysmon output showing disk I/O.
