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Cheetah 10K.6 FC Product Manual, Rev. B

bus. The process of measuring off-line attribute data and saving data to the disc is uninterruptable. The maxi- mum on-line only processing delay is summarized below:

Maximum processing delay

 

 

On-line only delay

Fully-enabled delay

 

DEXCPT = 0, PERF = 1

DEXCPT = 0, PERF = 0

S.M.A.R.T. delay times

50 milliseconds

300 milliseconds

Reporting control

Reporting is controlled by the MRIE bits in the Informational Exceptions Control mode page (1Ch). Subject to the reporting method, the firmware will issue to the host an 01-5Dxx sense code. The error code is preserved through bus resets and power cycles.

Determining rate

S.M.A.R.T. monitors the rate at which errors occur and signals a predictive failure if the rate of degraded errors increases to an unacceptable level. To determine rate, error events are logged and compared to the number of total operations for a given attribute. The interval defines the number of operations over which to measure the rate. The counter that keeps track of the current number of operations is referred to as the Interval Counter.

S.M.A.R.T. measures error rates. All errors for each monitored attribute are recorded. A counter keeps track of the number of errors for the current interval. This counter is referred to as the Failure Counter.

Error rate is the number of errors per operation. The algorithm that S.M.A.R.T. uses to record rates of error is to set thresholds for the number of errors and their interval. If the number of errors exceeds the threshold before the interval expires, the error rate is considered to be unacceptable. If the number of errors does not exceed the threshold before the interval expires, the error rate is considered to be acceptable. In either case, the inter- val and failure counters are reset and the process starts over.

Predictive failures

S.M.A.R.T. signals predictive failures when the drive is performing unacceptably for a period of time. The firm- ware keeps a running count of the number of times the error rate for each attribute is unacceptable. To accom- plish this, a counter is incremented each time the error rate is unacceptable and decremented (not to exceed zero) whenever the error rate is acceptable. If the counter continually increments such that it reaches the pre- dictive threshold, a predictive failure is signaled. This counter is referred to as the Failure History Counter. There is a separate Failure History Counter for each attribute.

5.2.8Drive Self Test (DST)

Drive Self Test (DST) is a technology designed to recognize drive fault conditions that qualify the drive as a failed unit. DST validates the functionality of the drive at a system level.

There are two test coverage options implemented in DST:

1.Extended test

2.Short text

The most thorough option is the extended test that performs various tests on the drive and scans every logical block address (LBA) of the drive. The short test is time-restricted and limited in length—it does not scan the entire media surface, but does some fundamental tests and scans portions of the media.

If DST encounters an error during either of these tests, it reports a fault condition. If the drive fails the test, remove it from service and return it to Seagate for service.

5.2.8.1DST Failure Definition

The drive will present a “diagnostic failed” condition through the self-tests results value of the diagnostic log page if a functional failure is encountered during DST. The channel and servo parameters are not modified to test the drive more stringently, and the number of retries are not reduced. All retries and recovery processes are enabled during the test. If data is recoverable, no failure condition will be reported regardless of the number of retries required to recover the data.

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Seagate ST373307FC, ST336607FC Milliseconds, Reporting control, Determining rate, Predictive failures, Drive Self Test DST

ST336607FC, ST373307FC, ST3146807FC specifications

The Seagate ST373307FC, ST3146807FC, and ST336607FC are robust hard disk drives designed for enterprise environments where reliability and performance are critical. Each model offers distinct features suited to various data storage needs, reflecting Seagate's commitment to innovation in storage technology.

The ST373307FC is a 73GB Fibre Channel hard drive that operates at 15,000 RPM, making it exceptionally fast for read and write operations. This drive employs a 4GB cache, enhancing its performance by allowing quicker access to frequently used data. With a 3.5-inch form factor, the ST373307FC is built for high-density environments, delivering reliable access to data. Its Fibre Channel interface supports high-speed connections, essential for data-intensive applications like databases and virtualization.

Next in line, the ST3146807FC offers a capacity of 146GB, also operating at 15,000 RPM. This drive features an 8GB cache, which significantly improves its data transfer rates, making it ideal for transactional workloads. The ST3146807FC is engineered to minimize latency and maximize throughput, ensuring that enterprises can access critical data swiftly and efficiently. Additionally, its rugged construction is designed to withstand the demands of continuous operation, providing peace of mind for businesses with strict uptime requirements.

Lastly, the ST336607FC has a substantial storage capacity of 300GB and shares the 15,000 RPM operational speed that characterizes this high-performance line. With a similar 8GB cache as the ST3146807FC, it offers excellent performance for read-intensive and write-heavy applications. The ST336607FC is also designed with enhanced thermal management features, supporting cooler operations in densely packed server environments. This model is particularly suited for applications such as data warehousing and online transaction processing, where speed and reliability are paramount.

Each of these drives utilizes advanced technologies like Native Command Queuing (NCQ), which optimizes the order of read and write requests. These features, combined with Seagate's reputation for durability and performance, make the ST373307FC, ST3146807FC, and ST336607FC excellent choices for enterprise applications requiring high-speed data access and exceptional reliability. In environments where data integrity and uptime are critical, these drives provide the robust performance necessary to meet demanding storage needs.