Toward a Unified Performance and Power Consumption NAND Flash Memory Model of Embedded and Solid State Secondary Storage Systems

This paper presents a set of models dedicated to describe a flash storage subsystem structure, functions, performance and power consumption behaviors. These models cover a large range of today's NAND flash memory applications. They are designed to be implemented in simulation tools allowing to estimate and compare performance and power consumption of I/O requests on flash memory based storage systems. Such tools can also help in designing and validating new flash storage systems and management mechanisms. This work is integrated in a global project aiming to build a framework simulating complex flash storage hierarchies for performance and power consumption analysis. This tool will be highly configurable and modular with various levels of usage complexity according to the required aim: from a software user point of view for simulating storage systems, to a developer point of view for designing, testing and validating new flash storage management systems

On Benchmarking Embedded Linux Flash File Systems

Due to its attractive characteristics in terms of performance, weight and power consumption, NAND flash memory became the main non volatile memory (NVM) in embedded systems. Those NVMs also present some specific characteristics/constraints: good but asymmetric I/O performance, limited lifetime, write/erase granularity asymmetry, etc. Those peculiarities are either managed in hardware for flash disks (SSDs, SD cards, USB sticks, etc.) or in software for raw embedded flash chips. When managed in software, flash algorithms and structures are implemented in a specific flash file system (FFS). In this paper, we present a performance study of the most widely used FFSs in embedded Linux: JFFS2, UBIFS,and YAFFS. We show some very particular behaviors and large performance disparities for tested FFS operations such as mounting, copying, and searching file trees, compression, etc.Comment: Embed With Linux, Lorient : France (2012

Performance Evaluation of Flash File Systems

Today, flash memory are strongly used in the embedded system domain. NAND flash memories are the building block of main secondary storage systems. Such memories present many benefits in terms of data density, I/O performance, shock resistance and power consumption. Nevertheless, flash does not come without constraints: the write / erase granularity asymmetry and the limited lifetime bring the need for specific management. This can be done through the operating system using dedicated Flash File Systems (FFSs). In this document, we present general concepts about FFSs, and implementations example that are JFFS2, YAFFS2 and UBIFS, the most commonly used flash file systems. Then we give performance evaluation results for these FFSs.Comment: Colloque du GDR SoC-SiP, Paris : France (2012

Commentary on Lee & Zaryab

The study by Lee & Zaryab (this issue) investigated whether listening to high-groove music affects how heterosexual observers rate the attractiveness of people from the opposite sex. They found a very small positive effect of high-groove music on the male observers, but no effect on females. In my commentary, I argue for a more conservative interpretation of the results than the one offered by the authors

Adult native septic arthritis: a review of 10 years of experience and lessons for empirical antibiotic therapy

Objectives To review the epidemiology of native septic arthritis to establish local guidelines for empirical antibiotic therapy as part of an antibiotic stewardship programme. Methods We conducted a 10 year retrospective study based on positive synovial fluid cultures and discharge diagnosis of septic arthritis in adult patients. Microbiology results and medical records were reviewed. Results Between 1999 and 2008, we identified 233 episodes of septic arthritis. The predominant causative pathogens were methicillin-susceptible Staphylococcus aureus (MSSA) and streptococci (respectively, 44.6% and 14.2% of cases). Only 11 cases (4.7%) of methicillin-resistant S. aureus (MRSA) arthritis were diagnosed, among which 5 (45.5%) occurred in known carriers. For large-joint infections, amoxicillin/clavulanate or cefuroxime would have been appropriate in 84.5% of cases. MRSA and Mycobacterium tuberculosis would have been the most frequent pathogens that would not have been covered. In contrast, amoxicillin/clavulanate would have been appropriate for only 75.3% of small-joint infections (82.6% if diabetics are excluded). MRSA and Pseudomonas aeruginosa would have been the main pathogens not covered. Piperacillin/tazobactam would have been appropriate in 93.8% of cases (P < 0.01 versus amoxicillin/clavulanate). This statistically significant advantage is lost after exclusion of diabetics (P = 0.19). Conclusions Amoxicillin/clavulanate or cefuroxime would be adequate for empirical coverage of large-joint septic arthritis in our area. A broad-spectrum antibiotic would be significantly superior for small-joint infections in diabetics. Systematic coverage of MRSA is not justified, but should be considered for known carriers. These recommendations are applicable to our local setting. They might also apply to hospitals sharing the same epidemiolog

Drum Groove Corpora

Patterned microtiming deviations from metronomic regularity are ubiquitous in the performance of metered music. The relevance of microtiming to the perception of music has been studied since the 1980s. Most recently, microtiming has been investigated as a cause of groove (i.e., the pleasant urge to move in response to music). The study of microtiming relies on the availability of microtiming data. This report presents three large corpora of onset timings derived from drum kit performances in popular Anglo-American popular music styles. These data are made freely available (CC 4.0 license) to provide a resource for use by analysts and experimenters alike. They offer a common point of reference for future studies into the temporal facets of music performance. The datasets adhere to FAIR principles; they thus facilitate replication of analyses and experimental stimuli

Adolescents' self-reported health status, behaviours and health issues addressed during routine school doctor consultations in Switzerland: an observational study

BACKGROUND We aimed to investigate the self-reported health status and behaviours of 7th-grade adolescents, associations with gender and educational track, as well as health issues addressed during routine school doctor consultations in Switzerland. METHODS Data on health status and behaviours, specifically general well-being, stimulant and addictive substance use, bullying/violence, exercise, nutrition and health protection, and puberty/sexuality, were drawn from routinely collected self-assessment questionnaires from 1076 (of a total of 1126) students from 14 schools in the Swiss canton of Zug in 2020. Data on health issues addressed in school doctor consultations were collected by nine school doctors (for 595 individual consultations). Multilevel logistic regression analyses were used to investigate the association of gender and educational track with unfavourable health status or behaviours. RESULTS Although 92% (n = 989) of the students reported being happy or satisfied overall, 21% (n = 215) often or almost always felt sad, and 5-10% had repeatedly been seriously physically hurt (n = 67), sexually harassed with words (n = 88) or experienced uncomfortable physical contact (n = 60). Female gender and a lower educational track were associated with unfavourable health status. In 90% (n = 533) of the school doctor consultations, at least one topic of disease prevention or health promotion was addressed, whereby the topics addressed depended strongly on the individual school doctors. CONCLUSIONS Our findings revealed that unfavourable health status and behaviours were prevalent among adolescents but the health topics addressed in school doctor consultations were not tailored to students' self-reported health issues. A school-based approach that strengthens adolescents' health literacy and provides opportunities for patient-centred counselling has the potential to improve the current and future health of adolescents and, ultimately, adults. To realise this potential, it is essential for school doctors to be sensitised and trained to address students' health concerns. Emphasis should be placed on the importance of patient-centred counselling, the high prevalence of bullying, and gender and educational differences