Separating data and log is still a good idea, so store the Journal, WIJ, SYS and CacheTemp on separate disk controllers from each other and from the main DB(s).

Run ^GCOMPACT

Set the packing density to 100% if no updates

Export/import globals to pack them more densely on disk Defragmentation

Change subscript order to exploit constant or range predicates more effectively

Store each master map and its indexes on different disks

Separating data and log is still a good idea, so store the Journal, WIJ, SYS and CacheTemp on separate disk controllers from each other and from the main DB(s).
Note: the Journal (transaction log) should be entirely isolated from all other I/O activity – no other files should exist on the drives that contain the log file.  This ensures that, with the exception of transaction log backup and the occasional rollback – nothing disturbs the sequential nature of transaction log activity.

Use of RAID 10 especially important for CacheTemp – this system database is used heavily in most environments

Buy/Use fastest disks for often-queried DBs and indexes

Pre-allocate Cache.Dat and/or OS Defrag