TOSHIBA Storage Products for ICT Society 43
Feature Articles
Feature Articles
(2) Data queuing function
Reduces processing time by executing the write
operations of several commands together after storing
write data in the cache area.
(3) Cache function
Temporarily holds data to be read or written to/from
magnetic disks, improve command responses, and
optimizes processing in response to various access
forms from the host.
By expanding the data buffer capacity from 16 MB of the
previous model to 32 MB, we improved cache hit rates
and realized high performance.
Furthermore, we realized both high performance and low
power consumption by introducing a multi-level automatic
power saving algorithm and command-driven forcible
power saving as power saving functions.
An optional self-encryption drive (SED) function, which
allows the HDD itself to internally encrypt data, and a data
integrity field (DIF) function, which allows data protection
to be controlled at the system level, are supported.
5. Conclusion
We developed a high-performance 2.5-inch enterprise
class HDD with a rotation speed of 15,000 rpm and
an average seek time of 2.7 ms. During development,
we employed new technologies for the mechanical
components, servo control section, and controller firmware
section to enable high reliability and high performance.
Going forward, Toshiba will continue to push forward
with the development of HDDs for the enterprise market
featuring both higher performance and higher quality.

4.2.1. Maintainability and high reliability

The drive has a self-monitoring analysis reporting
technology (SMART) function, which warns of critical
HDD failures in advance, to realize a full-fledged
implementation of a logging function for detailed failure
analysis. The drive also has a self-test function, a self-
diagnostic function which allows the status of the HDD to
be diagnosed if the system requires it.
End-to-end data protection (an error detection function
executed upon any component failure) and a disk-surface-
defect avoidance function ensure data reliability at all
times. Furthermore, the following processes are executed
in the background, which may improve reliability during
continuous long-term operation.
(1) Background media scan (BMS) function
Performs a full scan of the data area at regular in-
tervals to detect recoverable errors in advance and
automatically recover them.
(2) System area (SA) saving function
Improves the log function by periodically saving
system information on the HDD into the SA, which is
isolated from the user-accessible areas.

4.2.2. High functionality, high performance,

and low power consumption

We optimized and improved the following three basic HDD
functions.
(1) Reordering function
Executes command processing in the shortest possi-
ble period of time by optimizing the execution order of
received commands (up to 128 commands).
Toru
IWAMOTO
Storage Products
Div.
Akihiko
MAKITA
Storage Products
Div.
Tatsuro
SASAMOTO
Storage Products
Div.
Keiichi
YORIMITSU
Storage Products
Div.