Choose the
unique content from source itself when you start a backup. It does utilize some
processing and memory from the source system so size it well.
Source based
deduplication is also very powerful in ensuring that you utilize minimum
network bandwidth during the backups. The backup application will create blocks
of data on source and then store their hashes there at source and send unique
data on the network. This is good for backups only if it is sized well. Catalog
created by some applications is large enough to cause trouble for the
performance of the source system which could be a production system.
Source based
deduplication also gives good results for file system backups. A traditional
approach takes long for file system backup that has millions of small files
taking days for getting written especially during a full backup cycle. Source
based deduplication in this case picks up only the changed content of the
changed files reducing the amount of data travelling on the network
irrespective of the backup level set.
Global
deduplication on the target further reduces the amount of data stored.