American Megatrends StorTrends 1300 User Manual page 216

Let us consider an example where a volume holds a Microsoft® Exchange Database. The
growth of email users, email data and corresponding regulatory push (see the next section
for more information on Information Retention Regulations) to retain emails for an
extended period will result in messages and data to be scattered all over the space with
various degrees of importance. The relevance of emails and corresponding references to
them sharply tapers off with the passage of time. StorTrends has a powerful Data
Collection and Trending agent that keeps track of near term and long term block usage. It
automatically demotes historically less referenced blocks from a more expensive storage
tier to a less expensive one. Access of cheaper tiers is also monitored and blocks are
promoted back to faster tiers appropriately. In this way, by detecting stale data and
moving them out to lower tiers makes more room for newer and frequent data in faster
tiers.
198 StorTrends® 1300 User's Guide (StorTrends iTX version 2.7)