Hesela / Structured knowledge

Storage Knowledge Corpus

Storage definitions, connected to their evidence.

866 terms · Page 8 of 29

A-Z

  1. Term

    Fencing token

    A fencing token identifies an ownership generation that a receiving service checks to reject operations from an obsolete owner.

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  2. Term

    Fibre Channel

    Fibre Channel (FC) is a serial networking technology standardised by INCITS committee T11, built on frames exchanged between ports over point-to-point links, switched fabrics or loops, and widely used to carry SCSI (and NVMe) traffic between servers and storage in a SAN.

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  3. Term

    FICON

    FICON (Fibre Connection) is the IBM mainframe I/O channel protocol that runs as a Fibre Channel upper-level protocol (the FC-SB family), carrying channel commands and data between mainframe channels and storage control units such as DASD and tape.

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  4. Term

    FIEMAP

    A Linux ioctl interface that reports file extent mappings and associated state flags over a requested logical byte range.

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  5. Term

    File descriptor

    A file descriptor is a nonnegative integer used by a process to refer to an open file description for operations such as reading, writing or closing.

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  6. Term

    File extent

    A filesystem mapping for a contiguous range of file blocks and the storage blocks backing that range.

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  7. Term

    File preallocation

    Reserving filesystem allocation for a file range before the application writes that range's data.

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  8. Term

    File storage

    File storage exposes data as named files in a hierarchical directory tree that many clients access over a network file-sharing protocol such as NFS (registered port 2049) or SMB, so clients operate on files rather than on raw blocks.

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  9. Term

    File truncation

    File truncation changes a regular file to a specified byte length, discarding data beyond a shorter end or extending it when supported.

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  10. Term

    Filesystem aging

    Filesystem aging is the evolution of allocation layout through file operations that can degrade performance even when the logical contents remain comparable.

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  11. Term

    Filesystem consistency invariant

    A filesystem consistency invariant is a rule relating filesystem metadata that must hold at a defined consistency boundary.

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  12. Term

    Filesystem defragmentation

    Reorganizing a file's storage extents to reduce fragmentation while preserving its logical contents.

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  13. Term

    Filesystem freeze

    A filesystem freeze temporarily blocks modifications after completing ongoing filesystem transactions and flushing dirty filesystem data, metadata and logs to storage.

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  14. Term

    First-in first-out cache replacement

    First-in first-out cache replacement evicts the resident entry that was inserted earliest, without refreshing its queue position on a hit.

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  15. Term

    FITS checksum convention

    The FITS checksum convention embeds 32-bit one's-complement checks for an HDU's data records and its complete header/data unit in DATASUM and CHECKSUM header keywords.

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  16. Term

    Fixed block architecture

    Fixed block architecture (FBA) is a mainframe disk format in which every data record has the same length (512 bytes on the devices documented here) and each block is addressed by a sequential block number, instead of by cylinder, head and record number as in count-key-data (CKD) devices.

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  17. Term

    Flash data retention

    Flash data retention is the ability of programmed NAND data to remain recoverable over time without refresh under specified wear, storage and read conditions.

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  18. Term

    Flash module

    A flash module is a replaceable unit that packages NAND dies and a controller on one board or in one package, used in arrays and servers either in a standard form factor (for example E1.S, 111.49 mm long) or in a custom card shape.

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  19. Term

    Flash translation layer (FTL)

    A flash translation layer maps host logical addresses to physical flash locations and manages flash-specific operations such as reclamation.

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  20. Term

    Flexible Image Transport System (FITS)

    FITS is a scientific data format that stores images and other data in header/data units with metadata describing their representation.

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  21. Term

    Floating-gate flash

    A flash cell design that stores charge on an electrically isolated conductive gate to alter the transistor's threshold voltage.

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  22. Term

    Floppy disk

    Removable flexible magnetic disk media used for software distribution and PC backup before optical and flash.

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  23. Term

    Fluid dynamic bearing

    A fluid dynamic bearing (FDB) in an HDD spindle motor carries the rotating shaft or hub on a thin pressurised film of lubricant (usually oil, sometimes air) generated by grooves such as herringbone patterns, so that the rotor and stator do not touch while spinning, replacing the rolling balls of a ball-bearing spindle.

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  24. Term

    Flux-control microwave-assisted magnetic recording (FC-MAMR)

    Flux-control microwave-assisted magnetic recording (FC-MAMR) is Toshiba's HDD write-assist technique that uses a spintronic device between the write poles to redirect magnetic flux toward the recording medium and strengthen the write field.

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  25. Term

    Flying height

    Flying height is the physical clearance between a flying HDD head/slider region and the disk surface.

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  26. Term

    Force Unit Access

    Force Unit Access is a write-request property requiring the flagged data to reach nonvolatile storage before that request is reported complete.

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  27. Term

    Forward assembly area

    A forward assembly area buffers requested chunks in future restore-output order using advance knowledge from the backup recipe.

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  28. Term

    Free-space fragmentation

    Free-space fragmentation is the division of a filesystem's available allocation space into separated contiguous runs.

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  29. Term

    fs-verity

    fs-verity is a Linux filesystem facility that verifies the immutable contents of selected files against a cryptographic file digest.

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  30. Term

    fsync

    fsync is a file-synchronization operation that requests persistence of a file's modified data and associated metadata before reporting completion.

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