scholarly journals Protocols for wide-area data-intensive applications: Design and performance issues

Author(s):  
Yufei Ren ◽  
Tan Li ◽  
Dantong Yu ◽  
Shudong Jin ◽  
Thomas Robertazzi ◽  
...  
2021 ◽  
Vol 48 (3) ◽  
pp. 120-121
Author(s):  
Myungsuk Kim ◽  
Myoungjun Chun ◽  
Duwon Hong ◽  
Yoona Kim ◽  
Geonhee Cho ◽  
...  

NAND flash memory has revolutionized how we manage data in modern digital systems, significant improvements are needed in flash-based storage systems to meet the requirements of emerging data-intensive applications. In this paper, we address the problem of NAND aging markers that represent the wearing degree of NAND cells. Since all flash operations are affected by the wearing status of NAND cells, an accurate NAND aging marker is critical to develop flash optimization techniques. From our evaluation study, we first show that the existing P/E cyclebased aging marker (PeWear) is inadequate to estimate the actual aging status of NAND blocks, thus losing opportunities for further optimizations. To overcome the limitations of PeWear, we propose a new NAND aging marker, RealWear, based on extensive characterization studies using real 3D TLC flash chips. By considering multiple variables that can affect the NAND cell wear, RealWear can accurately indicate the actual wear status of NAND blocks during run time. Using three case studies, we demonstrate that RealWear is effective in enhancing the lifetime and performance of a flash storage system. Our experimental results showed that RealWear can extend the lifetime of individual NAND blocks by 63% and can reduce the GC overhead by 21%. Furthermore, RealWear significantly mitigates read latency fluctuations, guaranteeing that the read latency can be bounded with at most 2 read retry operations.


Sensors ◽  
2021 ◽  
Vol 21 (5) ◽  
pp. 1709
Author(s):  
Agbotiname Lucky Imoize ◽  
Oluwadara Adedeji ◽  
Nistha Tandiya ◽  
Sachin Shetty

The 5G wireless communication network is currently faced with the challenge of limited data speed exacerbated by the proliferation of billions of data-intensive applications. To address this problem, researchers are developing cutting-edge technologies for the envisioned 6G wireless communication standards to satisfy the escalating wireless services demands. Though some of the candidate technologies in the 5G standards will apply to 6G wireless networks, key disruptive technologies that will guarantee the desired quality of physical experience to achieve ubiquitous wireless connectivity are expected in 6G. This article first provides a foundational background on the evolution of different wireless communication standards to have a proper insight into the vision and requirements of 6G. Second, we provide a panoramic view of the enabling technologies proposed to facilitate 6G and introduce emerging 6G applications such as multi-sensory–extended reality, digital replica, and more. Next, the technology-driven challenges, social, psychological, health and commercialization issues posed to actualizing 6G, and the probable solutions to tackle these challenges are discussed extensively. Additionally, we present new use cases of the 6G technology in agriculture, education, media and entertainment, logistics and transportation, and tourism. Furthermore, we discuss the multi-faceted communication capabilities of 6G that will contribute significantly to global sustainability and how 6G will bring about a dramatic change in the business arena. Finally, we highlight the research trends, open research issues, and key take-away lessons for future research exploration in 6G wireless communication.


2021 ◽  
Vol 55 (1) ◽  
pp. 88-98
Author(s):  
Mohammed Islam Naas ◽  
François Trahay ◽  
Alexis Colin ◽  
Pierre Olivier ◽  
Stéphane Rubini ◽  
...  

Tracing is a popular method for evaluating, investigating, and modeling the performance of today's storage systems. Tracing has become crucial with the increase in complexity of modern storage applications/systems, that are manipulating an ever-increasing amount of data and are subject to extreme performance requirements. There exists many tracing tools focusing either on the user-level or the kernel-level, however we observe the lack of a unified tracer targeting both levels: this prevents a comprehensive understanding of modern applications' storage performance profiles. In this paper, we present EZIOTracer, a unified I/O tracer for both (Linux) kernel and user spaces, targeting data intensive applications. EZIOTracer is composed of a userland as well as a kernel space tracer, complemented with a trace analysis framework able to merge the output of the two tracers, and in particular to relate user-level events to kernel-level ones, and vice-versa. On the kernel side, EZIOTracer relies on eBPF to offer safe, low-overhead, low memory footprint, and flexible tracing capabilities. We demonstrate using FIO benchmark the ability of EZIOTracer to track down I/O performance issues by relating events recorded at both the kernel and user levels. We show that this can be achieved with a relatively low overhead that ranges from 2% to 26% depending on the I/O intensity.


Sign in / Sign up

Export Citation Format

Share Document