block data

block data

[′bläk ‚dad·ə]
(computer science)
A statement in FORTRAN which declares that the program following is a data specification subprogram.
McGraw-Hill Dictionary of Scientific & Technical Terms, 6E, Copyright © 2003 by The McGraw-Hill Companies, Inc.

block level

Reading and writing a disk at the physical level. The disk controller in every computer and server reads and writes the disks at the block level. In storage area networks (SANs), where the disks are in cabinets external to the server, read/write access is also at the block level.

Block Level vs. File Level
An application accesses data by file name (logical), which is translated into block level (physical) for reading and writing by the operating system's file system.

Users always deal with data at the file level; however, database and network administrators may get involved at the block level, because they can stipulate where data are physically stored for performance issues.

NAS vs. SAN
Although a stand-alone unit with its own disks, a network attached storage (NAS) device has its own file system for file level access. Because a SAN uses block level access and has no file system with its associated overhead, a SAN is much faster than a NAS. See SAN, NAS and file system.

Remote Block Level Access
With IP storage, block level access can be extended via the IP protocol to remote locations. See SAN and IP storage.

Blocks Are Also Logical
Modern drives maintain their own tables of good and bad sectors and remap requests on the fly. As a result, the physical block reads and writes are translated by the drive into actual sector reads and writes, making the block access somewhat like a logical request, rather than 100% physical.


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References in periodicals archive ?
The S BLOCK Data Processing Unit was also officially launched at the summit.
The new method used in this Harvard study combines census block data, addresses, building footprints from satellite data, and land use data (called ABODE - Allocation By Occupied Domicile Estimate).
The solution offers a single system to manage both file and block data, enabling consolidation of workloads for ease of use.
When the user exceeds a set limit, a warning will be shown and they can choose to block data for the rest of the day or keep going.
Through partnerships with leading technology providers — we offer solutions for high-level network monitoring and deep packet inspection as well as solutions for Network Access Control, WAN Optimization, Vulnerability & Threat Monitoring, Monitor & Block Data Leakage, and Endpoint Security.
In the face of a complex health care system, where many incentives exist to block data sharing, greater interoperability clearly enables better patient outcomes, said lifeIMAGE President and CEO, Matthew A.
So we can insert the block data of the parallel mode between blocks of the serial working mode and hide the execution time of the parallel mode block data inside that of the serial working mode block data.
If we use 160 bits to store the reference data block data and we use the prime DCT coefficients to represent the image block and quantified and encoded the DCT coefficients to 80 bits, the calculated ratio R is 1/2.
- Identify Namespace return list of Namespace Identifiers - Get Log Page command change for Retain Asynchronous Event functionality - Globally Unique Updates - SGL Dword Simplification - Firmware Update Granularity - Namespace Optimal IO Boundary - Non-Operational Power State Permissive Mode - Data Transfer Direction for opcodes shall be valid - Reservations Changes - Operation Denied status code - Deallocated Value for Logical Block Data