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.

6.2.5Thermal monitor

Savvio 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 65°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 65°C, however, you can set it to any value in the range of 0 to 65°C. If you specify a temperature greater than 65°C in this field, the temperature is rounded down to 65°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

 

 

Savvio 10K.3 SAS Product Manual, Rev. G

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Seagate ST9300503SS, ST9300603SS Predictive failures, Thermal monitor, Temperature Log Page 0Dh Parameter Code Description

ST9146803SS, ST9300603SS, ST9300503SS, ST9146603SS, ST9146703SS specifications

Seagate has long been a key player in the storage technology industry, and its enterprise-class hard drives such as the ST9300503SS, ST9300403SS, ST9146603SS, ST9146803SS, and ST9146703SS stand out for their performance, reliability, and innovative features. Designed primarily for use in data centers and server environments, these drives offer a range of specifications suited for high-demand applications.

The Seagate ST9300503SS is a 300GB 2.5-inch SAS (Serial Attached SCSI) hard drive that operates at 10,000 RPM, which is essential for ensuring rapid data access. It provides a data transfer rate of 6 Gb/s and features Seagate's AgileArray technology, which enhances RAID performance and reliability by improving data integrity and optimizing power consumption. The drive is also designed to withstand the rigors of enterprise use, boasting a mean time between failures (MTBF) rating of 1.6 million hours.

In contrast, the ST9300403SS offers a similar 300GB capacity and speed, but with slight variations in features that make it better suited for specific applications. This drive also supports SAS 2.0 and includes features that enhance error recovery and data protection.

The ST9146603SS is another powerhouse, providing 146GB of storage. Operating at the same high spindle speed of 10,000 RPM, it is optimized for low-latency performance. This makes it highly suitable for transactional applications and environments where quick access to data is crucial. Like its counterparts, this drive is built with robust technologies that ensure reliable operation and enhanced data security.

The ST9146803SS bumps up the storage capacity to 300GB while maintaining the same impressive speed and performance features. Its incorporation of Seagate’s SeaTach technology allows for advanced communication protocols, which facilitate faster data transfers and lower latency.

Finally, the ST9146703SS also offers 146GB of storage and is known for its energy efficiency features that reduce operational costs in large-scale deployments. All these drives support a wide range of operating systems, making them versatile picks for businesses looking to upgrade their storage solutions.

Overall, the Seagate ST9300503SS, ST9300403SS, ST9146603SS, ST9146803SS, and ST9146703SS are essential components in any enterprise environment, delivering high performance, reliability, and advanced technology features that meet the critical demands of modern data storage.