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.

5.2.5Thermal monitor

Cheetah 15K.6 FC drives implement a temperature warning system which:

1.Signals the host if the temperature exceeds a value which would threaten the drive.

2.Signals the host if the temperature exceeds a user-specified value.

3.Saves a S.M.A.R.T. data frame on the drive which exceeds the threatening temperature value.

A temperature sensor monitors the drive temperature and issues a warning over the interface when the tem- perature exceeds a set threshold. The temperature is measured at power-up and then at ten-minute intervals after power-up.

The thermal monitor system generates a warning code of 01-0B01 when the temperature exceeds the speci- fied limit in compliance with the SCSI standard. The drive temperature is reported in the FRU code field of mode sense data. You can use this information to determine if the warning is due to the temperature exceeding the drive threatening temperature or the user-specified temperature.

This feature is controlled by the Enable Warning (EWasc) bit, and the reporting mechanism is controlled by the Method of Reporting Informational Exceptions field (MRIE) on the Informational Exceptions Control (IEC) mode page (1Ch).

The current algorithm implements two temperature trip points. The first trip point is set at 68°C which is the maximum temperature limit according to the drive specification. The second trip point is user-selectable using the Log Select command. The reference temperature parameter in the temperature log page (see Table 1) can be used to set this trip point. The default value for this drive is 68°C, however, you can set it to any value in the range of 0 to 68°C. If you specify a temperature greater than 68°C in this field, the temperature is rounded down to 68°C. A sense code is sent to the host to indicate the rounding of the parameter field.

Table 1: Temperature Log Page (0Dh)

Parameter Code

Description

 

 

0000h

Primary Temperature

 

 

0001h

Reference Temperature

 

 

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Cheetah 15K.6 FC Product Manual, Rev. D

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Seagate ST3450856FC manual Determining rate, Predictive failures, Thermal monitor, Parameter Code Description

ST3450856FC specifications

The Seagate ST3146356FC, ST3300656FC, and ST3450856FC are hard disk drives designed for enterprise storage solutions, showcasing Seagate’s commitment to performance, reliability, and advanced technology in the data storage sector. These drives cater primarily to the needs of data centers and businesses requiring robust data management capabilities.

The ST3146356FC is notable for its 146GB capacity, 3.5-inch form factor, and 10,000 RPM spindle speed. It employs Serial Attached SCSI (SAS) interface technology, which ensures high data transfer rates and reliable connectivity. This model is designed to handle a multitude of demanding applications, such as online transaction processing and enterprise resource planning, requiring fast access to data and minimized latency.

The ST3300656FC, with a capacity of 300GB, continues the trend of high performance set by its predecessor. This drive also features the 10,000 RPM spindle speed and SAS interface, providing enhanced data throughput and optimized performance for intensive workloads. The drive is built with advanced error recovery features that enhance data integrity and reliability, making it suitable for critical applications where data loss is unacceptable.

The ST3450856FC offers even greater capacity, with a robust 450GB storage option. Like the other models, it operates at 10,000 RPM and utilizes the SAS interface. This drive is designed for scalability, ensuring that it can meet the evolving storage demands of enterprises. It is also equipped with sophisticated technologies such as Seagate's Enhanced S.M.A.R.T. (Self-Monitoring, Analysis, and Reporting Technology), providing continual monitoring of the drive’s health and performance metrics.

All three models share key characteristics, including advanced thermal and power management technologies that help maintain optimal operating temperatures and reduce energy consumption. This is crucial in data center environments where maximizing efficiency is vital for operational cost management. Additionally, Seagate's commitment to low acoustic noise levels ensures quieter operation, which is beneficial in environments where sound levels must be controlled.

In summary, the Seagate ST3146356FC, ST3300656FC, and ST3450856FC drives are engineered for enterprise environments demanding high reliability, speed, and capacity. Their advanced technologies, including SAS interface and enhanced error management systems, make these drives ideal for critical applications in data-intensive sectors. With reinforced durability, effectiveness in managing large volumes of data, and a focus on energy efficiency, these drives symbolize the pinnacle of Seagate's storage innovations for enterprise solutions.