If write caching is enabled (WCE=1), then the drive may return Good status on a write command after the data has been transferred into the cache, but before the data has been written to the medium. If an error occurs while writing the data to the medium, and Good status has already been returned, a deferred error will be gen- erated.

The Synchronize Cache command may be used to force the drive to write all cached write data to the medium. Upon completion of a Synchronize Cache command, all data received from previous write commands will have been written to the medium.

Table 16 show the mode default settings for these drives.

4.5.2Prefetch operation

If the Prefetch feature is enabled, data in contiguous logical blocks on the disc immediately beyond that which was requested by a Read command are retrieved and stored in the buffer for immediate transfer from the buffer to the host on subsequent Read commands that request those logical blocks (this is true even if cache operation is disabled). Though the prefetch operation uses the buffer as a cache, finding the requested data in the buffer is a prefetch hit, not a cache operation hit.

To enable Prefetch, use Mode Select page 08h, byte 12, bit 5 (Disable Read Ahead - DRA bit). DRA bit = 0 enables prefetch.

The drive does not use the Max Prefetch field (bytes 8 and 9) or the Prefetch Ceiling field (bytes 10 and 11).

When prefetch (read look-ahead) is enabled (enabled by DRA = 0), the drive enables prefetch of contiguous blocks from the disc when it senses that a prefetch hit will likely occur. The drive disables prefetch when it decides that a prefetch hit is not likely to occur.

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Seagate ES.2 FC, ST31000640FC manual Prefetch operation
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ST31000640FC, ES.2 FC specifications

The Seagate ES.2 FC, model ST31000640FC, is a high-performance hard drive designed specifically for enterprise environments. This drive is engineered to provide reliable and efficient data storage, catering to the demands of critical business applications, data centers, and server infrastructures.

One of the standout features of the ST31000640FC is its large storage capacity. With a 1TB capacity, it offers ample space for storing vast amounts of data, making it an excellent choice for businesses that require extensive storage solutions. This capacity enables the drive to support extensive databases, applications, and virtualized environments without compromising performance.

The Seagate ES.2 FC utilizes Fibre Channel (FC) interface technology, which is known for its high-speed data transfer capabilities. Operating at 4 Gbps, this interface facilitates faster communication between the drive and the server, significantly enhancing overall system performance. The Fibre Channel technology also improves data integrity through its ability to manage large amounts of data traffic efficiently.

In terms of performance specifications, the ST31000640FC boasts a rotational speed of 7200 RPM and a sustained data transfer rate that offers quick access to information. Additionally, it features an advanced caching mechanism that optimizes read and write operations, ensuring rapid data retrieval and improved application responsiveness.

The drive's advanced error recovery and data protection mechanisms, such as the Seagate PowerTrim technology, work to minimize downtime and data loss. This is particularly crucial for enterprise applications that demand high availability and reliability. PowerTrim intelligently manages the drive’s internal resources to enhance performance and durability.

Another essential characteristic of the Seagate ES.2 FC is its enterprise-grade reliability. It boasts a mean time between failures (MTBF) rating of 1.2 million hours, indicating its robustness for continuous operation in demanding environments. Furthermore, it is designed to operate in a range of temperatures, ensuring consistent performance across various operational conditions.

Lastly, the Seagate ES.2 FC incorporates vibration tolerance and advanced acoustic performance features, which help to reduce noise and ensure quieter operation in data center environments. This makes it an attractive option for enterprises looking to optimize their infrastructure while minimizing disturbances.

In summary, the Seagate ES.2 FC, ST31000640FC hard drive is an excellent choice for enterprises seeking a balance of large storage capacity, high-speed performance, and reliability in a Fibre Channel environment. With its array of technologies and robust characteristics, it meets the rigorous demands of modern business storage needs.
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