Loading web-font TeX/Main/Regular
IEEE Xplore Search Results

Showing 1-25 of 68 resultsfor

Filter Results

Show

Results

The emergence of shingle recording technology has made the high-capacity disk possible, which does not change the original magnetic medium, but add a shielding layer to the original disk. However, random write performance of the current shingle disk is very poor, which becomes an important factor restricting the extention of its applications. We propose an Optimization Shingle Disk Model short for...Show More
The reliability of the traditional RAID system can be guaranteed through the data backup and data redundant technologies. The system can utilize data recovery and reconstruction operations to recover data in case of the disk failure; however it will result in longer data recovery time and negative impact on system performances. Moreover, the possibility of secondary failure will be increased durin...Show More
Solid-State Disks (SSD) are widely used in government and security departments owing to its faster speed of data access, more durability, more shock and drop, no noise, lower power consumption, lighter weight compared with Magnetic disk. As a result, the demand of security for storing data has been generated. The Advanced Encryption Standard (AES) is today's key data encryption standard for protec...Show More
As a result of the Internet's rapid growth, there has been a huge increase in the amount of information generated and shared by people all over the world. Demand for large-scale storage system is growing rapidly. Instead of disk arrays, decentralized storage systems that consist of a cluster of nodes with locally attached disks have become a cost effective solution. This paper describes the design...Show More
The computer science and industry improves a lot these years, the storage architecture has been changed lots. Solid state drives have been introduced years, but the price of the flash memory doesn't decrease, though its technology increase a lot. When talks to magnetic hard drives, the density and capacity are always the hot research areas since there have more difficulties on improving disk perfo...Show More
Most solid state drives use DRAM for device's cache, the volatile memory provides the I/O Caching ability, and maintains the drives' mapping table (indicates the correspondence between physical unit and logical unit). However, when the drives' power shut down unexpected, the volatile DRAM memory may lose the caching data, which did not have time to write to the drives' storage media, so the dirty ...Show More
As a result of the multimedia rapid growth, there has been a huge increase in the amount of information generated and shared by people all over the world. Demand for large-scale multimedia storage system is growing rapidly. This paper describes the design and implementation of the Two-level metadata server for distributed multimedia storage system (DMSS). The DMSS divides the logical view of the s...Show More
When RAID volume is newly created, the data in RAID is then initialized. The process formats the RAID volume to clear any previously data and initialize redundancy information. This paper investigates others' initialization methods, and proposes a new initialization method. It makes RAID initialization and I/O request processing parallel, and reduces initialization time efficiently. Testing result...Show More
RAID has been a key component for constructing enterprise storage system. The target module supports host for the access interface of storage devices. This paper discusses the function of the target module based on a prototype of Fiber Channel RAID system. Further analyses the internal architecture of target module and gives an elaboration on the various workflows of the read/write access. Finally...Show More
3-D triple-level cell (3-D TLC) NAND flash has high storage density and capacity, but degrading data reliability due to high raw bit error rates induced by a certain number of program/erase cycles. To guarantee data reliability, low-density parity-check (LDPC) codes are selected as the error correction codes in modern flash memories because of strong error correction capability. However, directly ...Show More
nand flash-based storage devices have gained a lot of popularity in recent years. Unfortunately, flash blocks suffer from limited endurance. For guaranteeing flash reliability, flash manufactures also prescribe a specified number of program and erase (P/E) cycles to define the endurance of flash blocks within the same chip. To extend the service lifetime of a flash-based device, existing works als...Show More
To expand the capacity of a RAID-5 array with additional disks, data have to be migrated between disks to leverage extra space and performance gain. Conventional methods for expanding RAID-5 are very slow because they have to migrate almost all existing data and recalculate all parity blocks. This paper proposes a new online expansion method for RAID-5, named parity-based migration (PBM). This met...Show More
Persistent key-value (KV) stores are an integral part of storage infrastructure in data centers. Emerging non-volatile memory (NVM) technologies are potential alternatives for future memory architecture design. In this study, we use NVM to optimize the KV store and propose RangeKV, an LSM-tree based persistent KV store built on a heterogeneous storage architecture. RangeKV uses RangeTab in NVM to ...Show More
3-D NAND flash memory is gradually being widely used in solid state drives (SSDs), leading to increasing storage capacity. However, the read performance of SSD is sacrificed for decoding operations which are executed to guarantee the data reliability. No matter whether the data have bit errors, they will be sent to error correcting code (ECC) engine to decode, introducing a high read delay of SSD....Show More
Previous works proposed building file systems and organizing the metadata with KV stores because KV stores handle entries of various sizes efficiently and have excellent scalability. The emergence of the byte-addressable persistent memory (PM) enables metadata service to be faster than before by tailoring the KV store for the PM. However, existing PM-based KV stores cannot handle the workloads of ...Show More

DROP: A New RAID Architecture for Enhancing Shared RAID Performance

;;;;

The Computer Journal
Year: 2017 | Volume: 60, Issue: 6 | Journal Article |
Enterprise storage systems are generally shared by multiple servers in a storage area network environment. Our experiments as well as industry reports have shown that disk arrays show poor performance when multiple servers share one RAID due to resource contention as well as frequent disk head movements. We have studied IO performance characteristics of several shared storage settings of practical...Show More

DROP: A New RAID Architecture for Enhancing Shared RAID Performance

;;;;

Year: 2017 | Volume: 60, Issue: 6 | Journal Article |
NAND flash memory is widely used in various computing systems. However, flash blocks can sustain only a limited number of program/erase (P/E) cycles, which are referred to as the endurance. On one hand, in order to ensure data integrity, flash manufacturers often define the maximum P/E cycles of the worst block as the endurance of flash blocks. On the other hand, blocks exhibit large endurance var...Show More
This paper proposes a new SSD cache architecture, DEFT-cache, Delayed Erasing and Fast Taping, that maximizes I/O performance and reliability of RAID storage. First of all, DEFT-Cache exploits the inherent physical properties of flash memory SSD by making use of old data that have been overwritten but still in existence in SSD to minimize small write penalty of RAID5/6. As data pages being overwri...Show More
Disk data density improvement will eventually be limited by the super-paramagnetic effect for perpendicular recording. While various approaches to this problem have been proposed, Shingled Magnetic Recording (SMR) holds great promise to mitigate the problem of density scaling cost-effectively by overlapping data tracks. However, the inherent properties of SMR limit Shingled Write Disk (SWD) applic...Show More
Cloud computing is an elastic computing model that the users can lease the resources from the rentable infrastructure. Cloud computing is gaining popularity due to its lower cost, high reliability and huge availability. To utilize the powerful and huge capability of cloud computing, this paper is to import it into data mining and machine learning field. As one of the most influential and open comp...Show More
The storage capacity of NAND Flash has increased by scaling down to smaller cell size and using multi-level storage technology, but data reliability is degraded by severer retention errors. To ensure data reliability, error correction codes (ECC) are adopted, such as BCH and low-density parity check (LDPC) codes. However, BCH codes are insufficient when raw bit error rates (RBER) caused by retenti...Show More
Key-value (KV) stores play an increasingly critical role in supporting diverse large-scale applications in modern data centers hosting terabytes of KV items which even might reside on a single server due to virtualization purposes. The combination of the ever-growing volume of KV items and storage/application consolidation is driving a trend of high storage density for KV stores. Shingled Magnetic...Show More
As disk volume grows rapidly with terabyte disk becoming a norm, RAID reconstruction time in case of a failure takes prohibitively long time. This paper presents a new RAID architecture, S2-RAID, allowing the disk array to reconstruct very quickly in case of a disk failure. The idea is to form skewed sub RAIDs (S2-RAID) in the RAID structure so that reconstruction can be done in parallel dramatica...Show More
NAND flash-based Solid State Devices (SSDs) offer the desirable features of high performance, energy efficiency, and fast growing capacity. Thus, the use of SSDs is increasing in distributed storage systems. A key obstacle in this context is that the natural unbalance in distributed I/O workloads can result in wear imbalance across the SSDs in a distributed setting. This, in turn can have signific...Show More
As disk volume grows rapidly with terabyte disk becoming a norm, RAID reconstruction process in case of a failure takes prohibitively long time. This paper presents a new RAID architecture, {\rm S}^{2}-RAID, allowing the disk array to reconstruct very quickly in case of a disk failure. The idea is to form skewed sub-arrays in the RAID structure so that reconstruction can be done in parallel dra...Show More