scholarly journals iLife: Safely Extending Lifetime for Memory-Oriented SSD

Electronics ◽  
2019 ◽  
Vol 8 (6) ◽  
pp. 610
Author(s):  
Erci Xu ◽  
Shanshan Li

Currently, the roles of SSDs have been diversified significantly. Apart for storage purposes, users can also utilize flash drives to cache hot data or buffering incoming writes to achieve high throughput. In this case, the endurance study of Solid State Drives (SSDs) has become an increasingly important topic as users rely on such research to reliably avoid early retirement of their old drives in laptops or machines in data centers. However, current manufacturers adopt Program/Erase (P/E) cycle-based life indicators to estimate the remaining lifetime of an SSD, which is often too conservative due to longtime data retention concerns. In this paper, we begin by analyzing the inaccuracy and other potential issues of existing P/E cycle-based life indicators for SSDs under memory-oriented workloads. To construct an accurate life indicator, we conduct a more extensive and sophisticated experiment to wear out eight SSDs from four different vendors. By monitoring the device status extracted from the standard S.M.A.R.T.attributes in the experiment, we make eleven interesting findings on the relationship between the device lifetime and different types of errors observed. Based on our unique findings, we propose iLife, a pattern-based life indicator for SSDs under memory-oriented workloads. Our evaluation of iLife on a different set of six SSDs shows that iLife is a more accurate life indicator, with an average of 14.2% higher accuracy on lifetime estimation and up to 21.2% safe lifetime extension compared to existing P/E cycle-based indicators.

Electronics ◽  
2021 ◽  
Vol 10 (4) ◽  
pp. 486
Author(s):  
Yongjae Chun ◽  
Kyeore Han ◽  
Youpyo Hong

Owing to their advantages over hard disc drives (HDDs), solid-state drives (SSDs) are widely used in many applications, including consumer electronics and data centers. As erase operations are feasible only in block units, modification or deletion of pages cause invalidation of the pages in their corresponding blocks. To reclaim these invalid pages, the valid pages in the block are copied to other blocks, and the block with the invalid pages is initialized, which adversely affects the performance and durability of the SSD. The objective of a multi-stream SSD is to group data by their expected lifetimes and store each group of data in a separate area called a stream to minimize the frequency of wasteful copy-back and initialization operations. In this paper, we propose an algorithm that groups the data based on input/output (I/O) types and rewrite frequency, which show significant improvements over existing multi-stream algorithms not only for performance but also for effectiveness in covering most applications.


Author(s):  
Jungil Mok ◽  
Byungki Kang ◽  
Daesun Kim ◽  
Hongsun Hwang ◽  
Sangjae Rhee ◽  
...  

Abstract Systematic retention failure related on the adjacent electrostatic potential is studied with sub 20nm DRAM. Unlike traditional retention failures which are caused by gate induced drain leakage or junction leakage, this failure is influenced by the combination of adjacent signal line and adjacent contact node voltage. As the critical dimension between adjacent active and the adjacent signal line and contact node is scaled down, the effect of electric field caused by adjacent node on storage node is increased gradually. In this paper, we will show that the relationship between the combination electric field of adjacent nodes and the data retention characteristics and we will demonstrate the mechanism based on the electrical analysis and 3D TCAD simulation simultaneously.


Author(s):  
Вадим Леонидович Афанасьевский

В статье анализируется проблема взаимоотношений философии права и научной теории права. Рассматриваемая проблема стала особенно актуальной в российском образовательном пространстве в связи с введением после длительного перерыва в государственный образовательный стандарт магистратуры по юриспруденции учебной дисциплины «Философия права». Автор статьи в качестве базисного принимает тезис, согласно которому философия права, являясь сферой философской мысли, и теория права как область научного социогуманитарного знания представляют собой разные типы теоретического дискурса. Исходя из этого, в статье выстраивается теоретическая концепция, согласно которой задачей философии права как философского типа мышления является конструирование или экспликация онтологических, эпистемологических, аксиологических, феноменологических оснований для формирования и функционирования научных теоретико-правовых и историко-правовых построений. Для реализации поставленной в статье задачи подробно рассматриваются ключевые характеристики как теории философского типа, так и идеалов, норм и характеристик научного знания. Выявленное различие экстраполируется на взаимоотношение теории права как продукта научного творчества и философии права как конструкции, задающей базовые мировоззренческие смыслы. В качестве примера выработанных философией права и государства оснований научных теорий прогресса, государства, морали и права, автор приводит взгляды мыслителей западноевропейской философской классики: Т. Гоббса, Ж.-Ж. Руссо, И. Канта, Г.В.Ф. Гегеля. Именно их философские концепции предопределили образы теоретико- и историко-правовых учений XVIII, XIX, XX и даже начала XXI в. Таким образом, отношение философии права и теории права выстраивается по «вертикали»: от онтологического основания к возведению теоретико-правовых и историко-правовых научных построений. The article analyzes the problem of the relationship between the philosophy of law and the scientific theory of law. The problem under consideration has become especially urgent in the Russian educational space in connection with the introduction of the Philosophy of Law discipline master's degree in law after a long break. The author of the article takes as the basis the thesis that the philosophy of law, being the sphere of philosophical thought, and the theory of law as a field of scientific socio-humanitarian knowledge are different types of theoretical discourse. Based on this, the article builds a theoretical concept according to which the task of the philosophy of law as a philosophical type of thinking is the construction or explication of ontological, epistemological, axiological, phenomenological grounds for the formation and functioning of concrete scientific theoretical and legal and historical and legal constructions. To implement the task posed in the article, the key characteristics of both a theory of a philosophical type and ideals, norms and characteristics of scientific knowledge are examined in detail. The revealed difference is extrapolated to the relationship between the theory of law as a product of scientific creativity and the philosophy of law as a construction that sets basic philosophical meanings. As an example of the foundations of the scientific theories of progress, state, morality and law developed by the philosophy of law and the state, the author gives the views and thinkers of the West European philosophical classics T. Hobbes, J.-J. Russo, I. Kant, G.V.F. Hegel. It was their philosophical concepts that predetermined the images of theoretical and historical-legal doctrines of the XVIII, XIX, XX and even the beginning of the XXI centuries. Thus, the attitude of the philosophy of law and the theory of law is built along the «vertical»: from the ontological foundation to the construction of theoretical and historical and historical legal scientific constructions.


2019 ◽  
Vol 25 (14) ◽  
pp. 1696-1716 ◽  
Author(s):  
Ida Frugaard Stroem ◽  
Helene Flood Aakvaag ◽  
Tore Wentzel-Larsen

This study investigates the relationship between the characteristics of different types of childhood violence and adult victimization using two waves of data from a community telephone survey (T1) and a follow-up survey, including 505 cases and 506 controls, aged 17-35 years (T2). The logistic regression analyses showed that exposure to childhood abuse, regardless of type, was associated with adult victimization. Exposure to multiple types of abuse, victimization both in childhood and in young adulthood, and recency of abuse increased these odds. Our findings emphasize the importance of assessing multiple forms of violence when studying revictimization. Practitioners working with children and young adults should be attentive to the number of victimization types experienced and recent victimization to prevent further abuse.


2020 ◽  
Vol 0 (0) ◽  
Author(s):  
Sumit Chandra ◽  
Shahnaz Fatima ◽  
Raghuraj Singh Suryavanshi

AbstractIn the present scenario, data centers serve many functionalities like storage, transfer of data, supporting web applications, etc. In data centers, various levels of hierarchy different types of switches are required; therefore, multifunctional data centers are desired. This paper discusses a novel design for optical switch which can be placed at various levels of hierarchy. In the proposed design, multifunctionality contention resolution schemes which consider electronic and optical buffering and all-optical negative acknowledgment (AO-NACK) are considered. In buffering technologies, contending packets are stored in either in electronic RAM or in fiber delay lines. In case of the AO-NACK scheme, contending packets are blocked, and a negative acknowledgment is sent back to the transmitting node and blocked packets are retransmitted. For various considered schemes, Monte Carlo simulation have been performed, results in terms of packet loss probability are presented, and it has been found that the performance of optical buffering is much superior to electronic buffering and AO-NACK schemes. It is found that, in the AO-NACK scheme, the numbers of retransmitted packets due to contention blocking are 33,304 which can be reduced to 7, by using a small amount of buffer at each node.


Biomolecules ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 1021
Author(s):  
Carla Abrahamian ◽  
Christian Grimm

Microphthalmia-associated transcription factor (MITF) is the principal transcription factor regulating pivotal processes in melanoma cell development, growth, survival, proliferation, differentiation and invasion. In recent years, convincing evidence has been provided attesting key roles of endolysosomal cation channels, specifically TPCs and TRPMLs, in cancer, including breast cancer, glioblastoma, bladder cancer, hepatocellular carcinoma and melanoma. In this review, we provide a gene expression profile of these channels in different types of cancers and decipher their roles, in particular the roles of two-pore channel 2 (TPC2) and TRPML1 in melanocytes and melanoma. We specifically discuss the signaling cascades regulating MITF and the relationship between endolysosomal cation channels, MAPK, canonical Wnt/GSK3 pathways and MITF.


2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Sarah E. Knowles ◽  
Dawn Allen ◽  
Ailsa Donnelly ◽  
Jackie Flynn ◽  
Kay Gallacher ◽  
...  

Abstract Background Knowledge mobilisation requires the effective elicitation and blending of different types of knowledge or ways of knowing, to produce hybrid knowledge outputs that are valuable to both knowledge producers (researchers) and knowledge users (health care stakeholders). Patients and service users are a neglected user group, and there is a need for transparent reporting and critical review of methods used to co-produce knowledge with patients. This study aimed to explore the potential of participatory codesign methods as a mechanism of supporting knowledge sharing, and to evaluate this from the perspective of both researchers and patients. Methods A knowledge mobilisation research project using participatory codesign workshops to explore patient involvement in using health data to improve services. To evaluate involvement in the project, multiple qualitative data sources were collected throughout, including a survey informed by the Generic Learning Outcomes framework, an evaluation focus group, and field notes. Analysis was a collective dialogic reflection on project processes and impacts, including comparing and contrasting the key issues from the researcher and contributor perspectives. Results Authentic involvement was seen as the result of “space to talk” and “space to change”. "Space to talk" refers to creating space for shared dialogue, including space for tension and disagreement, and recognising contributor and researcher expertise as equally valuable to the discussion. ‘Space to change’ refers to space to adapt in response to contributor feedback. These were partly facilitated by the use of codesign methods which emphasise visual and iterative working, but contributors emphasised that relational openness was more crucial, and that this needed to apply to the study overall (specifically, how contributors were reimbursed as a demonstration of how their input was valued) to build trust, not just to processes within the workshops. Conclusions Specific methods used within involvement are only one component of effective involvement practice. The relationship between researcher and contributors, and particularly researcher willingness to change their approach in response to feedback, were considered most important by contributors. Productive tension was emphasised as a key mechanism in leading to genuinely hybrid outputs that combined contributor insight and experience with academic knowledge and understanding.


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