high-performance disk drives

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Analyzing the Performance of Spatial Indices on Hard Disk Drives and Flash-based Solid State Drives

Analyzing the Performance of Spatial Indices on Hard Disk Drives and Flash-based Solid State Drives

and provided a good performance in the spatial query processing. In special, the page size equal to 16KB guaranteed better performance on spatial queries with high selectivity. Regarding the cloud server, we highlight the following two situations. First, the Microsoft Azure offers a special treatment for virtual machines equipped with SSDs, resulting in a better maximum throughput and IOPS compared to virtual machines equipped with conventional disks. Thus, our experiments showed the best performance results on the virtual machine with SSD, in the most of the cases. Second, we can improve the performance of spatial indices stored on virtual machines with SSDs by taking into account the intrinsic characteristics of these storage devices. The reason is that the FAST-based spatial indices showed expressive performance gains in this environment. Therefore, our experiments showed that flash-aware spatial indices often improve the performance of spatial indexing on SSDs, independently of the running environment, compared to the direct use of disk-based spatial indices without any additional treatment.
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Andromeda Systems Price List Feb84 pdf

Andromeda Systems Price List Feb84 pdf

DUAL FLOPPY DISK COMPUTER SYSTEM WITH 11/2 CPU, EIS/FIS, 64KB MEMORY, 4 SERIAL CHANNELS, TWO 625KB DISK DRIVES 1.25MB TOTAL STORAGE RXOl MEDIA COMPATIBLE PLUS HIGH PERFORMANCE DOUBLE DEN[r]

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Hardware Guide E8 Series Storage Enclosure Revision 0.90 February,

Hardware Guide E8 Series Storage Enclosure Revision 0.90 February,

RAID 0, also referred to as striping, writes stripes of data across multiple disk drives. RAID 0 does not provide any data redundancy, but does offer the best high-speed data throughput. RAID 0 breaks up data into smaller blocks and then writes a block to each drive in the array. Disk striping enhances performance because multiple drives are accessed simultaneously; but the reliability of RAID Level 0 is less than any of its member disk drives due to its lack of redundancy.

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Engineered for Efficiency

Engineered for Efficiency

Flash-based solid-state disks (SSDs) help address some of these challenges. They have excellent read and random I/O performance and low latency, which are crucial for business applications, server virtualization, and VDI. However, due to high cost and write endurance issues, using flash-only arrays is only practical for a very limited set of applications. Consequently, data storage vendors have been promoting various hybrid combinations involving flash and hard drives. Some vendors have taken a bolt-on approach, which simply layers flash on top of disk as an additional tier. This approach fails to leverage flash in a cost-effective way; and does not maximize disk utilization. It does little to simplify IT administrators’ jobs as they now have to contend with management and data migration between multiple tiers of storage.
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Technology Update White Paper. High Speed RAID 6. Powered by Custom ASIC Parity Chips

Technology Update White Paper. High Speed RAID 6. Powered by Custom ASIC Parity Chips

It is true that the probability of a rebuild failure is smaller for a single array it is not smaller for the storage installation as a whole. Further, smaller arrays have many disadvantages. They require more parity drives and waste storage, limit volume sizes and thus risk “disk full” messages and numerous volume expansions and require more management intervention. Smaller arrays deliver reduced performance since a smaller number of disks reduces the stripe size and limits the parallel reading and writing that is provided by accessing many disks at once.

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An Empirical Study On the Recovery Speed of USB Flash Drives Utilizing Raid-5 Compared to HDDs and SSDs

An Empirical Study On the Recovery Speed of USB Flash Drives Utilizing Raid-5 Compared to HDDs and SSDs

The original magnetic hard disk drive was first created by IBM scientists in 1956 (Noyes & Dickinson, 1956, p. 42). The original setup featured 50 disks spaced 0.3 inches apart to allow space for reading and writing via magnetic heads (Fig. 2.1, Noyes & Dickinson, 1956, p. 42). Each disk had a magnetic coating, and the device utilized a motor to rotate the disks for access (Noyes & Dickinson, 1956, p. 43). Modern hard disk drives are composed of less disks (Fig. 2.2) but are capable of reading and writing far more information at much higher speeds (Anderson, Dykes, & Riedel, 2003, p. 247). However, the response times of these drives has fallen behind that of processors due to rotational latency (Ekker, Coughlin, & Handy, 2009, p. 2). The drives also suffer from natural “wear and tear associated with mechanical devices” (U.S. Patent No. 5,459,850, 1995) which culminated in the creation of a storage reliability method called Redundant Arrays of Inexpensive Disks (RAID) (discussed later in this chapter) to combat the unreliability of hard disk drives (Patterson, Gibson, & Katz, 1988, p. 110).
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Modeling and Simulation of an Induction Motor

Modeling and Simulation of an Induction Motor

The use of asynchronous motors particularly squirrel-cage rotor has increased tremendously since the day of its invention. They are being used as actuators in many types of industrial processes, robotics, house appliances (generally single-phase) and other similar applications. The reason for its daily increasing popularity can be primarily attributed to its simplicity in design, robust construction and cost effectiveness, high efficiency, reliability and good self –starting capability [1-3]. The analysis of induction motor is carried out in steady state whereby the machine is modeled as a second order electromechanical system.
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ServeRAID M5015 and M5014 SAS/SATA Controllers for IBM System x IBM Redbooks Product Guide

ServeRAID M5015 and M5014 SAS/SATA Controllers for IBM System x IBM Redbooks Product Guide

Any references in this information to non-IBM Web sites are provided for convenience only and do not in any manner serve as an endorsement of those Web sites. The materials at those Web sites are not part of the materials for this IBM product and use of those Web sites is at your own risk.IBM may use or distribute any of the information you supply in any way it believes appropriate without incurring any obligation to you. Information concerning non-IBM products was obtained from the suppliers of those products, their published announcements or other publicly available sources. IBM has not tested those products and cannot confirm the accuracy of performance, compatibility or any other claims related to non-IBM products. Questions on the capabilities of non-IBM products should be addressed to the suppliers of those products. This information contains examples of data and reports used in daily business operations. To illustrate them as completely as possible, the examples include the names of individuals, companies, brands, and products. All of these names are fictitious and any similarity to the names and addresses used by an actual business enterprise is entirely coincidental.
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SAS, SATA, and SCSI RAID Controllers Installation and User s Guide

SAS, SATA, and SCSI RAID Controllers Installation and User s Guide

Internal SAS cables are narrower than internal parallel SCSI cables. The connectors vary in size depending on the number of links they support, from single link connectors to 4-wide (or larger) connectors. Internal fan-out cables (shown in the next figure) let you attach four disk drives to a single 4-wide connector.

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TS-803_Service_Sep83.pdf

TS-803_Service_Sep83.pdf

Refer to the REMOVAL/REPLACEMENT & ADJUSTMENTS section of this manual and follow the procedures for removal of the FLOPPY DISK DRIVES.. Do not remove the drives fro[r]

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9R80448_820-II_CPM_2.2_Reference_Jun82.pdf

9R80448_820-II_CPM_2.2_Reference_Jun82.pdf

CP/M. The BDOS provides disk management by controlling one or nore disk drives containing independent file directories. The BDOS implements disk allocation strategies[r]

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SAS, SATA, and SCSI RAID Controllers Installation and User s Guide

SAS, SATA, and SCSI RAID Controllers Installation and User s Guide

A SAS expander device literally expands the number of end devices that you can connect together. Expander devices, typically embedded into a system backplane (see page 66), support large configurations of SAS end devices, including SAS cards and SAS and SATA disk drives. With expander devices, you can build large and complex storage topologies.

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Latency: The Heartbeat of a Solid State Disk. Levi Norman, Texas Memory Systems

Latency: The Heartbeat of a Solid State Disk. Levi Norman, Texas Memory Systems

This SNW tutorial session is about the number one reason an IT manager would move away from HDDs and towards solid state disks (SSD)...latency. More importantly low latency. Latency becomes less of just a number and more an important metric when considering implementing any serious performance storage related solution. Today low latency can only effectively be addressed by one particular type of storage architecture and that’s an enterprise SSD design. Latency in a technical environment is synonymous with delay. More succinctly latency in terms of a SSD is how long it will take for a request to complete its round trip cycle from the time the request enters the device to the time that it leaves the device with the “payload” in tow. In a storage world where metrics such as $/GB are entrenched as a de-facto standard of measurement, and $/IOPS has arisen to become a “relevant” metric, we continue to miss a critical discussion point. And that is that low latency is the most important thing that can be delivered to a performance sensitive application or a workhorse database environment. In this session we will discuss the merits of low latency solutions and what they mean when coupled with a high IOPS and a large bandwidth design. From a business
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High performance speed of the induction motor drives by the predictive control using space vector modulation

High performance speed of the induction motor drives by the predictive control using space vector modulation

AC induction motors have been widely used in industrial applications such as machine tools, steel mills and paper machines owing to their good performance provided by their solid architecture, low moment of inertia, low ripple of torque and high starting torque. some control techniques have been developed to regulate these induction motors servo drives in high- performance applications. One of the most popular technique is the indirect field oriented control method (Egiguren et al., 2008). The field-oriented technique guarantees the decoupling of torque and flux control commands of the induction motor, so that the induction motor can be controlled linearly as a separated excited d.c. motor. However, the control performance of the resulting linear system is still influenced by uncertainties, which are usually composed of unpredictable parameter variations, external load disturbances, measurement noise and unmodelled and nonlinear dynamics. therefore, many studies have been made on the motor drives in order to preserve the performance under these parameter variations and external load disturbances, such as nonlinear control, optimal control, variable structure system control, adaptive control, neural control and predictive control (Egiguren et al., 2008 and Marino et al., 1998).
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Dynastor FX300 Disk Drives Brochure Oct1976 pdf

Dynastor FX300 Disk Drives Brochure Oct1976 pdf

TRANSFER COMPLETE - One line This pulse is required for any write operation in wh ich the data transferred is not a multiple of the selected sector length.. The pulse causes the remainde[r]

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NavigatorTM. Deploying Data Protection the Dell Way Dedupe Your Data on the Fly IN THIS ISSUE

NavigatorTM. Deploying Data Protection the Dell Way Dedupe Your Data on the Fly IN THIS ISSUE

Data growth is one of the tallest hurdles fac- ing the enterprise data center, and managing that data has become an increasingly difficult propo- sition. It is not a question of “if” a disk drive will fail; it is a matter of “when” will a drive fail. It is an issue of how much data has been lost and how fast the staff can recover it. How many backups can be taken and preserved before the data center runs out of backup capacity? What is the recovery point objective (RPO) of your enterprise? How quickly does the data need to be recovered in order to satisfy your recovery time objective (RTO)? Due to the growth of backup data and the time that has been commit- ted to recover it, in many instances tape may no longer be a viable alternative for backup in your data center.
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ShareCenter Pro DNS User Manual. Contents

ShareCenter Pro DNS User Manual. Contents

 This feature is designed for fault-tolerant logical drives (RAID 0, 1, 5, 6, and 10). It is generally recommended to use physical drives of the same size in your disk arrays. When this is not possible, physical drives of different sizes will work but the system must adjust for the size differences by reducing or coercing the capacity of the larger drives to match the smaller ones. You can choose to enable Capacity Coercion and any one of four methods.

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MA QTB300 R0 QTB 3 Users Manual 1984 pdf

MA QTB300 R0 QTB 3 Users Manual 1984 pdf

which type of disk drives are to be used, the required pinout is surrounded by a white rectangle along with the drive type indicator: 8 8 inch floppy disk; 5 5.25 inch floppy disk; HD = [r]

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Wave_Mate_Z80_Super_Bullet_Manual_Feb84.pdf

Wave_Mate_Z80_Super_Bullet_Manual_Feb84.pdf

The following disk drive configuration tables are presented to aid in connection of eight inch and five inch floppy disk drives to the SUPER BULLET. It should b[r]

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Enhanced Rules Framework for Predicting Disk Drives Failures

Enhanced Rules Framework for Predicting Disk Drives Failures

Murray et al. [7] compared the performance of SVM, unsupervised clustering, rank-sum test and reverse arrangements test. In their subsequent work [8], they developed a new algorithm termed multiple-instance naive Bayes (mi-NB). They found that, on the dataset concerning 369 drives, ranksum test outperformed SVM for certain small set of SMART attributes (28:1% failure detection at 0% FAR). When using all features, SVM achieved the best performance of 50:6 % detection with 0% FAR.

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