Good post by George Crump (thank you)
One of the techniques that storage vendors use to reduce the cost of hard disk-based storage is deduplication. Deduplication is the elimination of redundant data across files. The technology is ideal for backup, since so much of a current copy of data is similar to the prior copy. The few extra seconds required to identify redundant data is worth the savings in disk capacity. Deduplication for primary storage is popular for all-flash arrays. While the level of redundancy is not as great, the premium price of flash makes any capacity savings important. In addition, given the excess performance of AFAs the deduplication feature can often be added without a noticeable performance impact. There is one process though where deduplication provides little value; archive. IT professionals need to measure costs differently when considering a storage destination for archive.
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