raheel - abstract presentation

8/6/2019 Raheel - Abstract Presentation

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LOGO

Raheel Ahmed Memon

Effective Writing & Presentation for Thesis Research

[email protected] 1


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www.wix.com/sindhu4sind/raheel

Contents

Introduction1

Original Abstract2

Problems in Original Abstract3

Improved Abstract4

2

Review of New Abstract5


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NAND Flash Memory

3www.wix.com/sindhu4sind/raheel


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A B C D

E F A B

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A B C D

E F A B

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C D D

BlockX

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ckY

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Garbage Collection

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Wear Leveling



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AMI: AN ADVANCED ENDURANCE MANAGEMENTTECHNIQUE FOR FLASH MEMORY STORAGE SYSTEMS

Authors

Sanam Shahla Rizvi and Tae-Sun Chung

School of Information and Computer Engineering, Ajou University, Korea

Published inInternational Arab Journal of Information Technology, Vol. 8, No. 1, January 2011



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Original Abstract

Flash memory is small size, lightweight, shock-resistant, nonvolatile, and consumes littlepower. Flash memory therefore shows promise for use in storage devices for consumer

electronics, mobile computers, wireless devices and embedded systems. However, flashmemory cannot be overwritten unless erased in advance. Erase operations are slow thatusually decrease system performance and consume power. The number of erase cycles is alsolimited, and a single worn-out block affects the usefulness of entire flash memory device.Therefore, for power conservation, better system performance and longer flash memorylifetime, system support for erasure management is necessary. In this paper, we propose a

novel idea of system software for garbage collection and wear-leveling called Allocation ofMemory Intellectually for NAND flash memories. Proposed scheme classifies data blocksintellectually according to their write access frequencies and improves the space utilization byallocating separate limited number of log blocks to both natures, hot and cold, of data blockswith proposed new system architecture. Our proposed cleaning scheme achieves a block toerase with optimal number of space utilization and minimum overhead of data migration. A

hybrid wear-leveling approach is also proposed to evenly wear-down flash memory. Proposedscheme enhances the system life time by managing the blocks according to their degree ofworn. We compared our proposed idea with two previous schemes. Our proposed ideaimproved system performance 95% for garbage collection and 36% for wear-leveling. Theevaluation results prove that our proposed scheme, AMI, outperforms both previous schemesparticularly with efficient flash bandwidth utilization and attempted erase operations.



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Problems in original Abstract

No proper Terminology

No proper organization

Redundancy Problem

Ambiguity in sentences



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Improved Abstract

NAND Flash memory is rapidly deploying as data storage for mobile devices and

embedded systems mainly because of its low electronic power, nonvolatile storage,high performance, physical stability, and portability. One technical challenge of flashmemory is that prewritten data cannot be dynamically overwritten. Beforeoverwriting existing data, a time-consuming erase operation on the used blocks mustprecede, which significantly degrades the overall write performance of flash memory.Also the numbers of erase operations are limited, and if the flash memory is not

evenly erased, it will soon be worn out. So for better performance and prolong flashmemory lifetime it is necessary to manage the erasure operation. We propose a novelidea of systems software architecture for garbage collection and wear-leveling calledas AMI (Allocation of Memory Intellectually). AMI classifies data blocks intellectuallyaccording to their write access frequencies and improves the space utilization byclassifying data blocks to hot and cold. Comparing two existing policies; greedy and

dual-pool, our proposed scheme AMI improved performance; 95% for garbagecollection and 36% for wear-leveling.



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Review of New Abstract

Proper Terminology

Proper Organization

No redundancy Problem

Clear to understand

Minimized number of Characters (254 to 175)



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Original vs Improved

Flash memory is small size, lightweight, shock-resistant,nonvolatile, and consumes little power. Flash memory therefore

shows promise for use in storage devices for consumerelectronics, mobile computers, wireless devices and embeddedsystems. However, flash memory cannot be overwritten unlesserased in advance. Erase operations are slow that usuallydecrease system performance and consume power. The numberof erase cycles is also limited, and a single worn-out blockaffects the usefulness of entire flash memory device. Therefore,for power conservation, better system performance and longerflash memory lifetime, system support for erasure managementis necessary. In this paper, we propose a novel idea of systemsoftware for garbage collection and wear-leveling calledAllocation of Memory Intellectually for NAND flash memories.Proposed scheme classifies data blocks intellectually accordingto their write access frequencies and improves the spaceutilization by allocating separate limited number of log blocks toboth natures, hot and cold, of data blocks with proposed newsystem architecture. Our proposed cleaning scheme achieves ablock to erase with optimal number of space utilization andminimum overhead of data migration. A hybrid wear-leveling

approach is also proposed to evenly wear-down flash memory.Proposed scheme enhances the system life time by managingthe blocks according to their degree of worn. We compared ourproposed idea with two previous schemes. Our proposed ideaimproved system performance 95% for garbage collection and36% for wear-leveling. The evaluation results prove that ourproposed scheme, AMI, outperforms both previous schemesparticularly with efficient flash bandwidth utilization andattempted erase operations.

NAND Flash memory is rapidly deploying as data storage formobile devices and embedded systems mainly because of its

low electronic power, nonvolatile storage, high performance,physical stability, and portability. One technical challenge offlash memory is that prewritten data cannot be dynamicallyoverwritten. Before overwriting existing data, a time-consuming erase operation on the used blocks must precede,which significantly degrades the overall write performance offlash memory. Also the numbers of erase operations arelimited, and if the flash memory is not evenly erased, it will soonbe worn out. So for better performance and prolong flashmemory lifetime it is necessary to manage the erasureoperation. We propose a novel idea of systems softwarearchitecture for garbage collection and wear-leveling called asAMI (Allocation of Memory Intellectually). AMI classifies datablocks intellectually according to their write access frequenciesand improves the space utilization by classifying data blocks tohot and cold. Comparing two existing policies; greedy and dual-pool, our proposed scheme AMI improved performance; 95% forgarbage collection and 36% for wear-leveling.



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raheel - abstract presentation

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