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Place the deduplication database and deduplicating vault on separate physical
devices
To increase the speed of access to a deduplication database, the database and the vault must be
located on separate physical devices.
It is best to allocate dedicated devices for the vault and the database. If this is not possible, at least
do not place a vault or database on the same disk with the operating system. The reason is that the
operating system performs a large number of hard disk read/write operations, which significantly
slows down the deduplication.
Selecting a disk for a deduplication database
The database must reside on a fixed drive. Please do not try to place the deduplication database
on external detachable drives.
Minimal disk access time is important. The best hard drive choice is an enterprise-grade
Solid-State Drive (SSD), though using a fast IDE hard drive (7200 RPM or faster) or a SCSI drive is
acceptable.
The volume to store the deduplication database should have at least 10 GB of free space. When
backing up a large number of machines, the required free space may exceed 10 GB.
The disk space required for a deduplication database can be estimated by using the following
formula:
S = U / 32 + 10
where
S – disk size, in GB
U – planned amount of unique data in the deduplication data store, in GB.
For example, if the planned amount of unique data in the deduplication data store is U=5 TB, the
deduplication database will require the free disk space not less than
S = 5*1024 / 32 + 10 = 170 GB
Selecting a disk for a deduplicating vault
For the purpose of data loss prevention, we recommend using RAID 10, 5 or 6. RAID 0 is not
recommended since it not fault tolerant. RAID 1 is not recommended because of relatively low speed.
There is no preference to local disks or SAN, both are good.
3 GB of RAM per 1 TB of unique data
It is not necessary to follow this recommendation if you do not experience a deduplication
performance problem. However, if the deduplication is too slow, adding more RAM to the storage
node may significantly raise the deduplication speed.
In general, the more RAM you have, the greater the deduplication database size can be, provided
that the deduplication speed is the same.
Only one deduplicating vault on each storage node
It is highly recommended that you create only one deduplicating vault on a storage node. Otherwise,
the whole available RAM volume may be distributed in proportion to the number of the vaults.
