Exchange 2010 includes improvements in performance, reliability, and high availability that enable organizations to run Exchange on a wide range of storage options. Building on improvements to disk input/output (IO) that were introduced in Exchange 2007, the latest version of Exchange requires less storage performance and is more tolerant of storage failures.
The improvements made to Exchange Server 2010 storage add new options to the menu of Exchange storage choices, including the use of Serial Advanced Technology Attachment (SATA) hard disk drives and Redundant Array of Inexpensive Disks (RAID)-less configurations. Whether administrators choose SAN, direct attached, or JBOD storage, Exchange helps them provide larger mailboxes at lower cost without sacrificing system availability.
IO Reductions: Exchange 2010 delivers up to a 50% reduction in disk IO from Exchange 2007 levels. This means that more disks meet the minimum performance required to run Exchange, driving down storage costs.
Optimizations for SATA Disks: IO patterns are optimized so that disk writes do not come in bursts. This removes a barrier that had previously limited the use of Serial Advanced Technology Attachment (SATA) desktop class hard disk drives disks.
Automatic Page Patching: Exchange Server 2010 is more resilient to storage problems. When corruption is caused by minor disk faults, Exchange automatically repairs the affected database pages using one of the database copies configured for high availability. Automatic detection and repair of data corruptions from minor disk errors means that you can take advantage of lower-cost storage options while maintaining system reliability.
JBOD Support: Exchange 2010 can be deployed with up to 16 replicated copies of each mailbox database, and fast database-level failover makes it possible for administrators to swap failed drives with minimal impact to users. This application-level redundancy allows RAID-less (JBOD) storage configurations to be used, resulting in dramatic cost savings.