Fujitsu ETERNUS DX100 S4 Design Manual page 113

3. SAN Functions
Operations Optimization (Deduplication/Compression)
In addition, if the DEDUP_SYS Volume capacity runs out or is close to running out, an SNMP
Trap, E-Mail, or syslog message is sent. The notification method is set with the "Setup Event
Notification" function. The notification target event is "Thin Provisioning Pool Rate". For more
details, refer to "ETERNUS Web GUI User's Guide".
*4: NAS user volumes are not supported.
The Memory Extension must be installed to use the Deduplication/Compression function. The
Memory Extension is installed as standard in the controller module for standard models of the
ETERNUS DX200 S4.
●
Performance When Using the Deduplication/Compression Function
The ETERNUS DX performs data deduplication/compression in synchronization with the I/O from
the server.
Using this function in environments where random access occurs is recommended. Data is inter-
•
mittently stored in Deduplication/Compression Volumes because data is appended.
• I/O response may significantly degrade when compared to systems that do not use the Dedupli-
cation/Compression function.
• Using this function in environments where the I/O size is 32KB or smaller is recommended. The
performance is affected in environments where the I/O size is large because data is deduplicated
and compressed every 4KB.
If the I/O size or the boundaries of the I/O address are not 4KB, the performance is affected be-
•
cause the parts less than 4KB are read in the ETERNUS DX.
• If I/Os are issued to the Deduplication/Compression Volumes, the CPU usage rate increases. The
performance of non-Deduplication/Compression Volumes may also be affected.
• The performance may decline when the Deduplication/Compression function is enabled. Using
the Deduplication/Compression function is not recommended for the following volumes.
- Volumes used to store performance-sensitive data
- Volumes configured with drives other than SSDs
Batch process (or sequential access) performance significantly degrades because data is writ-
•
ten to drives intermittently or a large amount of references and updates occur. In environ-
ments where sequential access occurs, using the Deduplication/Compression function is not
recommended.
• The Deduplication/Compression function becomes a disadvantage in terms of performance
and capacity if a volume stores data such as videos to which deduplication/compression is not
effective and the volume is set as a Deduplication/Compression Volume. Only enable either
the Deduplication function or the Compression function.
●
Configuration Method
Enabling the Deduplication/Compression function
•
From ETERNUS Web GUI or ETERNUS CLI, enable the Deduplication/Compression function for
the TPP. Not only can the Deduplication/Compression function be enabled, but the Deduplication
function or the Compression function can be individually enabled. Internal volumes (DEDUP_SYS
Volume and DEDUP_MAP Volumes) are created for each TPP that has the Deduplication/
Compression enabled. For details, refer to
115).
Fujitsu Storage ETERNUS DX100 S4/DX200 S4, ETERNUS DX100 S3/DX200 S3 Hybrid Storage Systems Design Guide (Basic)
"● Deduplication/Compression System Volumes" (page
113
Copyright 2023 Fujitsu Limited
P3AM-7642-32ENZ0