Fujitsu Eternus DX500 S3 - Extreme Cache; Extreme Cache Pool; Figure 12 Extreme Cache; Figure 13 Extreme Cache Pool

Extreme Cache
The Extreme Cache function uses PCIe Flash Modules (PFM) that are installed in the controller as the secondary
cache to improve the read access performance from the server.
Frequently accessed areas are written asynchronously to the PFM with I/O. When a read request is issued from
the server, data is read from the PFM to speed up the response.
Either the Extreme Cache function or the Extreme Cache Pool function can be used. Using the faster Extreme
Cache function is recommended.
Figure 12 Extreme Cache
ETERNUS DX
PFM
Cache memory
Disks
Controller
Read request
When there is a read
request, the response
for the request will be
faster by reading data
from the PFM instead
of reading data from
the disks.
Frequently accessed
areas are written to
the PFM
Extreme Cache Pool
The Extreme Cache Pool function uses SSDs in enclosures as the secondary cache to improve the read access per-
formance from the server.
Frequently accessed areas are written asynchronously to specified SSDs for Extreme Cache Pools. When a read
request is issued from the server, data is read from the faster SSD to speed up the response.
SSDs with a capacity of 400GB, 800GB, and 1.6TB can be used for Extreme Cache Pools. Either the Extreme Cache
function or the Extreme Cache Pool function can be used. Using the faster Extreme Cache function is recommen-
ded.
Figure 13 Extreme Cache Pool
ETERNUS DX
Extreme Cache Pool (SSDs)
Read request
Cache memory
Controller
Disks
When there is a read
request, the response
for the request will be
faster by reading data
from the SSDs instead
of reading data from
the disks.
Frequently accessed
areas are written to
the Extreme Cache
Pool (SSDs)
3. Basic Functions
Operations Optimization (Virtualization/Automated Storage Tiering)
35
FUJITSU Storage ETERNUS DX500 S3/DX600 S3 Hybrid Storage Systems
Overview
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