Efficient File System Research Articles

Postoperative pain in patients following endodontic treatment by XP-endo Shaper files: A systematic review and meta-analysis

Context: Postoperative pain occurs in 25%–60% of patients following endodontic treatment. It can significantly impact a patient’s quality of life and requires timely management or, preferably, prevention. Aims: The present systematic review was conducted aiming to analyze randomized controlled trials that compared postoperative pain in patients whose canals were shaped by XPS versus other endodontic file systems. Materials and Methods: A systematic search was performed using key terms “postoperative pain” AND “XP-endo Shaper” across multiple databases to identify relevant randomized controlled trials. Details concerning the study design, endodontic preparation, XP-endo Shaper-related factors, and pain assessment were recorded. The risk of bias was calculated using the RevMan 5.3 software. Meta-analysis done using the random effects model which was represented using forest plots. Results: Six studies evaluating a total of n = 290 samples of XP-endo Shaper file and other file systems each, respectively, were included in the final review and meta-analysis. The standard mean difference ranged from 0.8 to 2.88 with a mean of 1.04 (0.80–2.88) favoring other file systems. This signifies that the postoperative pain is on average 1.04 times more by other file systems as compared to XP-endo Shapers file although the difference was statistically nonsignificant (P > 0.05). Conclusions: XP-endo Shaper has proven to be a relatively more efficient file system that effectively cleans and shapes the root canals, including those with difficult anatomy.

Comparative Evaluation of Apical Debris Extrusion during Root Canal Preparation using Three Different Rotary File Systems: A Study Protocol

Background: Apical extrusion of debris leads to postoperative inflammation and endodontic failure.
 Objectives: To comparatively evaluate debris extrusion by using Trunatomy rotary files, 2 shape, ProTaper next rotary files.
 Methodology: Sixty Extracted single rooted human premolar teeth will be included in the study. After access opening, canal patency will be established by 15 K-file till the apical foramen followed by determination of working length by visual method. Now the samples will be divided into 3 groups: Group1: Trunatomy, Group 2: 2 shape file, Group 3: ProTaper Next files. Following this the manufacturer's instructions will be followed for the instrumentation. During instrumentation, extruded debris and irrigants will be collected into the preweighed test tubes. Following this, these tubes will be stored in an incubator at the temperature of 70°C for next 5 days. To evaluate the resultant weight of extruded debris, these test tubes will be weighed.
 Expected Results: Trunatomy rotary file system is expected to produce less debris than 2 shape, ProTaper Next file system.
 Conclusion: This study would be helpful for clinicians to choose better and efficient file system for instrumentation which produce comparatively less debris extrusion further reducing the chances of endodontic flareup.

HyCloud: Tweaking Hybrid Cloud Storage Services for Cost-Efficient Filesystem Hosting

Today’s cloud storage infrastructures typically provide two distinct types of services for hosting files: object storage like Amazon S3 and filesystem storage like Amazon EFS. In practice, a cloud storage user often desires the advantages of both—efficient filesystem operations with a low unit storage price. An intuitive approach to achieving this goal is to combine the two types of services, e.g., by hosting large files in S3 and small files together with directory structures in EFS. Unfortunately, our benchmark experiments indicate that the clients’ download performance for large files becomes a severe system bottleneck. In this article, we attempt to address the bottleneck with little overhead by carefully tweaking the usages of S3 and EFS. Guided by two key observations, we design and implement an open-source system called HyCloud. It automatically invokes the data APIs of S3 and EFS on behalf of users, and intelligently schedules the data transfer among S3, EFS and the clients in a distributed manner. Real-world evaluations demonstrate that the unit storage price of HyCloud is close to that of S3, and the filesystem operations are executed as quickly as in EFS in most times (sometimes even more quickly than in EFS).

Saksham: Resource Aware Block Rearrangement Algorithm for Load Balancing in Hadoop

Big Data Analytics demands huge processing power. Distributed computing seems to be a viable solution with the usage of commodity computers. But, processing big data optimally, on distributed systems poses the number of challenges, such as seamlessly integrating different resources of distributed systems. Hadoop provides this ease and hence is one of the most commonly used tools for the processing of big data. But, it is observed that the performance of Hadoop is compromised, when it comes to the heterogeneous environment. This paper proposes Saksham: The block rearrangement algorithm which optimizes the processing time by efficient file system management in the heterogeneous environment. Our proposed scheme successfully optimizes the big data processing over the homogeneous and heterogeneous environment. To achieve better performance for big data processing, we target two important aspects of heterogeneous distributed computing: file system management and process management. First, file system management basically controls the block placement and allows us to rearrange the blocks on specified nodes, considering the node’s storage and processing capability. Second, we use the concept of node labeling and scheduling to achieve better process management. The results prove that the proposed approach has optimized job execution time along with reduced latency and data-skew substantially.

DurableFS: a file system for NVRAM

With the availability of hybrid DRAM and NVRAM memory on the memory bus of CPUs, a number of file systems on NVRAM have been designed and implemented. In this paper we present the design and implementation of a file system on NVRAM called DurableFS, which provides atomicity and durability of file operations to applications. It provides ACID properties to transactions involving multiple files. Due to the byte level random accessibility of memory, it is possible to provide these guarantees without much overhead. We use standard techniques like copy on write for data, and a redo log for metadata changes to build an efficient file system which provides durability and atomicity guarantees to transactions. Benchmarks on the implementation shows that there is only a 7% degradation in performance due to providing these guarantees.

A Highly Recoverable and Efficient Filesystem

Data recovery is a significant problem that presents a real challenge to forensics investigators today. File carvers have traditionally helped mitigate these difficulties. However, two issues still present significant challenges – 1) Prior knowledge of file types is required for building file carvers, and 2) fragmentation prevents file carvers from successful recovery. In previous research, we proposed a framework for recovering deleted files without prior knowledge of file types and with the existence of fragmentation. In this paper, we introduce the design and a functioning implementation of our system by modifying an exFat filesystem running on top of FUSE. Evaluation of the overhead of our filesystem shows only a 5% decrease in performance in write operations when compared to an unmodified exFat filesystem, and almost identical read measurements. Our system also shows significantly better recovery rates in the presence of fragmentation when compared to two selected file carvers.

A compressed file system manager for flash memory based consumer electronics devices

NAND flash memory is widely used as secondary storage in portable consumer electronics devices such as smartphones and digital cameras. These devices often employ a compressed file system to efficiently manage the limited storage space. However, retrieving data from a compressed file system incurs substantial delays in launching applications due to additional decompression procedures at run time. This paper presents an efficient compressed file system manager (CFSM) that reduces the application launch time in portable consumer electronics devices. CFSM uses two novel techniques. One is the selective decompression that reduces the user-perceived latency by decompressing only the actually requested data acquired by a bulk read. The other technique is cost-aware replacement that preferentially evicts data from uncompressed file systems when memory is full because they are quicker to access than compressed data. A prototype of CFSM has been implemented on the Linux operating system. Measurement studies show that CFSM reduces the application launch latency by 28% on average compared to the well-known CramFS compressed file system.

File and metadata management for BESIII distributed computing

The BESIII experiment at the Institute of High Energy Physics (IHEP), Beijing, uses the high-luminosity BEPCII e+e− collider to study physics in the π-charm energy region around 3.7 GeV; BEPCII has produced the worlds largest samples of J/ϕ and ϕ’ events to date. An order of magnitude increase in the data sample size over the 2011-2012 data-taking period demanded a move from a very centralized to a distributed computing environment, as well as the development of an efficient file and metadata management system. While BESIII is on a smaller scale than some other HEP experiments, this poses particular challenges for its distributed computing and data management system. These constraints include limited resources and manpower, and low quality of network connections to IHEP. Drawing on the rich experience of the HEP community, a system has been developed which meets these constraints. The design and development of the BESIII distributed data management system, including its integration with other BESIII distributed computing components, such as job management, are presented here.

JavaFIRE: A Replica and File System for Grids

The work is focused on the creation of a replica and file transfers system for Computational Grids inspired on the needs of the High Energy Physics (HEP). Due to the high volume of data created by the HEP experiments, an efficient file and dataset replica system may play an important role on the computing model. Data replica systems allow the creation of copies, distributed between the different storage elements on the Grid. In the HEP context, the data files are basically immutable. This eases the task of the replica system, because given sufficient local storage resources any dataset just needs to be replicated to a particular site once. Concurrent with the advent of computational Grids, another important theme in the distributed systems area that has also seen some significant interest is that of peer-to-peer networks (p2p). P2p networks are an important and evolving mechanism that eases the use of distributed computing and storage resources by end users. One common technique to achieve faster file download from possibly overloaded storage elements over congested networks is to split the files into smaller pieces. This way, each piece can be transferred from a different replica, in parallel or not, optimizing the moments when the network conditions are better suited to the transfer. The main tasks achieved by the system are: the creation of replicas, the development of a system for replicas transfer (RFT) and for replicas location (RLS) with a different architecture that the one provided by Globus and the development of a system for file transfer in pieces on computational grids with interfaces for several storage elements. The RLS uses a p2p overlay based on the Kademlia algorithm.

The Experience in Designing and Evaluating the High Performance Cluster Netuno

This paper presents the Netuno supercomputer, a large-scale cluster installed at Federal University of Rio de Janeiro in Brazil. A detailed performance evaluation of Netuno is presented, depicting its computational and I/O performance, as well as the results for two real-world applications. Since building a high- performance cluster for running a wide range of applications is a non-trivial task, some lessons learned from assembling and operating this cluster, such as the excellent performance of the OpenMPI library, and the relevance of employing an efficient parallel file system over the traditional NFS system, can be useful knowledge to support the design of new systems. Currently, Netuno is being heavily used to run large scale simulations in the areas of ocean modeling, meteorology, engineering, physics, and geophysics.

디지털 컨버전스 기기를 위한 지역 버퍼 캐쉬 파일 시스템 설계 및 구현

오늘날 내장형 장치의 보급 증가와 반도체 및 저장장치 기술의 발달로 인해 디지털 컨버전스 기기들이 늘어나고 있다. 디지털 컨버전스 기기는 PMP, PDA, 스마트폰 등과 같이 하나의 디지털 기기에 통신, 동영상과 음악 재생, 전자 수첩, 전자 사전 등의 기능이 집적된 장치를 말한다. 따라서 이러한 장치에는 여러 기능을 관리하고 제어할 수 있는 효율적인 파일 시스템의 설계가 필요하다. 파일 시스템을 설계하는데 있어서는 소형화된 내장형 장치에 맞는 사이즈, 성능, 호환성 등을 고려해야 한다. 본 논문에서는 부분 버퍼 캐쉬 기법을 제안한다. 기존의 버퍼 캐쉬에 비해, 부분 버퍼 캐쉬는 FAT 데이터와 쓰기 전용 데이터를 저장한다. 시뮬레이션을 통해 파일 크기가 100KBye가 넘는 경우, 부분 버퍼 캐쉬를 사용함으로써 쓰기 성능을 30% 이상 증가시킬 수 있음을 보인다. Due to the growth of embedded systems and the development of semi-conductor and storage devices, digital convergence devises is ever growing. Digital convergence devices are equipments into which various functions such as communication, playing movies and wave files and electronic dictionarys are integrated. Example are portable multimedia players(PMPs), personal digital assistants(PDAs), and smart phones. Therefore, these devices need an efficient file system which manages and controls various types of files. In designing such file systems, the size constraint for small embedded systems as well as performance and compatibility should be taken into account. In this paper, we suggest the partial buffer cache technique. Contrary to the traditional buffer cache, the partial buffer cache is used for only the FAT meta data and write-only data. Simulation results show that we could enhance the write performance more than 30% when the file size is larger than about 100 KBytes.

XML 프로토콜을 지원하는 웹기반 rSPC 시스템

Accurate process control in the manufacturing industry is essential to survive in the competitive market. Statistical process control (SPC) system has been widely used to satisfy the ever-increasing quality control requirements. However, most commercial products in the market are not flexible, semi-automatic, and difficult to interface with other tools. In this paper, we propose an advanced rSPC (Real-Time SPC) system which is based on the web and supports XML protocol. We also provide a powerful graphic facility and an efficient file system to handle the data in real time. Even though the idea can be applied to any manufacturing system, our system is optimized to the semi-conductor industry and TFT/LCD industry. The system is implemented in C++ and COM/DCOM, and shows a good result.

A Simple and Efficient File System for Reprints

A Simple and Efficient File System for Reprints