Cache Management | Maxtor VL 17 manual

PRODUCTDESCRIPTION

Software ECC Correction

22 symbols, single burst, guaranteed

Automatic Park and Lock Operation

Immediately following power down, dynamic braking of the spinning disks delays momentarily allowing the read/write heads to move to an inner mechanical stop. A small fixed magnet holds the rotary actuator in place as the disk spins down. The rotary actuator is released only when power is again applied.

Cache Management

Buffer Segmentation

The data buffer is organized into two segments: the data buffer and the micro controller scratch pad. The data buffer is dynamically allocated for read and write data depending on the commands received. A variable number of read and write buffers may exist at the same time.

Read-Ahead Mode

Normally, this mode is active. Following a read request, disk read-ahead begins on the first sector and continues sequentially until the allocated buffer is full. If a read request is received during the read-ahead operation, the buffer is examined to determine if the request is in the cache. If a cache hit occurs, read- ahead mode continues without interruption and the host transfer begins immediately.

Automatic Write Reallocation (AWR)

This feature is part of the write cache and reduces the risk of data loss during deferred write operations. If a disk error occurs during the disk write process, the disk task stops and the suspect sector is reallocated to a pool of alternate sectors located at the end of the drive. Following reallocation, the disk write task continues until it is complete.

Write Cache Stacking

Normally, this mode is active. Write cache mode accepts the host write data into the buffer until the buffer is full or the host transfer is complete. A command complete interrupt is generated at the end of the transfer.

A disk write task begins to store the host data to disk. Host write commands continue to be accepted and data transferred to the buffer until either the write command stack is full or the data buffer is full. The drive may reorder write commands to optimize drive throughput.

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Maxtor VL 17 manual Cache Management

Contents

HA RD Drive Produc T MA Nual DiamondMaxVL REV EC no Section Description Date U T I O N Before You Begin Contents Handling and Installation Product Specifications Host Software Interface AT Interface Description Interface Commands Service and SupportGlossary Figures Abbreviations IntroductionMaxtor Corporation Manual Organization Numbering Signal ConventionsConventions Key Words Product Description DiamondMax VL 17 Key Features Functional / Interface Product Features On-the-Fly Hardware Error Correction Code ECC Logical Block AddressingDefect Management Zone DMZ Cache Management Major HDA Components Dual Drive Support Subsystem ConfigurationJumper Location/Configuration Cylinder Limitation Models and Capacities Product SpecificationsDrive Configuration Performance Specifications Parameter Standard Metric Physical Dimensions Environmental Limits Power RequirementsPower Mode Definitions EPA Energy Star Compliance Shock and Vibration Reliability Specifications Safety Regulatory Compliance Radiated Electromagnetic Field Emissions EMC ComplianceCanadian Emissions Statement Important Notice Handling and InstallationHard Drive Handling Precautions Pre-formatted Drive Multi-pack Shipping Container Unpacking and Inspection Physical Installation Recommended Mounting ConfigurationRepacking Drive Identification Information Handling PrecautionsTools for Installation System Requirements Hard Drive Identification General Requirements Mounting Drive in System Systems Using Cable SelectInstalling 5.25-inch Mounting Brackets and Rails Installing in a Device Bay Attaching System Cables Attaching Interface and Power Cables System Setup Setting the Bios CmosBios Cmos Parameters Hard Drive Preparation System Hangs During Boot Pin Description Summary Interface ConnectorPIN Signal AT Interface Description Pin Description Table PIN Name Signal Name Signal Description PIO Timing Timing Parameters Mode DMA Timing Ultra DMA Timing Mode MIN MAX Sustained Ultra DMA Data In Burst Device Terminating an Ultra DMA Data In Burst Initiating an Ultra DMA Data Out Burst Device Pausing an Ultra DMA Data Out Burst Device Terminating an Ultra DMA Data Out Burst Task File Registers Error RegisterFeatures Register Host Software Interface Device/Head Register Sector Count RegisterSector Number Register Cylinder Number Registers Command Register Command Name Command Code Parameters Used Timer Value TIME-OUT PeriodSummary Digital Input Register Control Diagnostic RegistersAlternate Status Register Device Control Register Reset and Interrupt Handling Reset HandlingInterrupt Handling Set Feature Commands Interface Commands Read Commands Read SectorsRead Verify Sectors Read Multiple Read DMA Write Verify Sectors Write CommandsSet Multiple Mode Write Sectors Write DMA Write Multiple Set Feature Commands Set Features ModeValue Description Power Mode Commands Sleep Mode Initialization Commands Word Content DescriptionIdentify Drive 15-8 = PIO data transfer mode = Write Cache enabled Initialize Drive Parameters Format Track Seek, Format and Diagnostic CommandsExecute Drive Diagnostic Error Code Description Execute S.M.A.R.T A.R.T. Command Set Support Service and SupportService Policy No Quibble Service MaxFax Service Customer ServiceInternet Glossary Access Time Cylinder Zero Gigabyte GB Logical Block Addressing Read Gate Signal THIN-FILM Media