Disk is the slowest part of the computer. Physical movements involved two ways: disk read/write head positioning to a track and spinning of the disk. Therefore it is crucial to have sufficient high-performance disk resources and configure them for optimal performance. RAM memory caching at different levels is helpful to overcome the disk sluggishness.
SQL Server disk drive configuration is reliable, high performance and relatively low cost:
Drive C 60 GB RAID 1 mirrored hard drive: operating
system / SQL Server software
Drive D 60 GB RAID 1 mirrored hard drive: temporary database (tempdb) data file
Drive E 300 GB RAID 5 hard drive array: application database
Drive F 60 GB RAID 1 mirrored hard drive: transaction
Drive G 120 GB RAID 0 hard drive: staging files - feeds, disk-to-disk-to-tape backups, etc.
Note: RAID 0 is not redundant
For additional performance gain place tempdb log on a dedicated RAID 1 drive.
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