External Sorting Research Articles

Clitic dislocations and clitics in French and Greek

This article focuses on Clitic Left Dislocation of XPs in French and Greek. By examining the interpretive properties of these XPs, primarily reconstruction properties, it concludes that they have been displaced from their first merge position via movement into (sometimes) a succession of hierarchically organized middle-field positions first above vP then above T and on to the left periphery via standard A or A-bar steps (no mixed options are needed). Furthermore, pronominal clitics have long raised questions regarding their surface distribution (external merge in situ only or not), and their interpretive properties. As these XPs are doubled by clitics, it becomes possible to allocate properties of the doublet (clitic, XP) to its individual members. This article concludes that these clitics all occur high, above T, in designated positions and that clitics do not have referential import, only the XPs that double them do.

Facilitating external sorting on SMR-based large-scale storage systems

In the big data era, retaining the capability to process and store the sheer amount of data has become a necessity for data-intensive computing. To meet the requirement of big data processing, the storage-centric computing concept of processing data within storage devices has gained its popularity over the years, because the latency and energy consumed by moving data between host systems and storage devices gradually exceed that of processing data. To process data for data-intensive computing, one of the fundamental data processing technique is external sorting, which is widely used in database management systems (DBMS) and Hadoop framework. On the other hand, to store the ever-increasing volumes of data, shingled magnetic recording (SMR) drives have been proposed to increase the areal density of conventional hard disk drives (HDDs) via overlapping adjacent tracks. The SMR drive is widely regarded as a promising technology for the big data application because SMR drives can boost the capacity of HDDs without significant technology changes. Nevertheless, the overlapped track layout of SMR drive imposes the sequential write constraint on incoming write traffic, thus worsening the efficiency of performing external sorting on SMR drives. Such an observation motivates us to propose an SMR-based External Merge Sort (SMR-EMS) strategy for SMR-based large-scale storage systems with the goals of alleviating the negative impacts of sequential write constraint and enhancing the performance of external sorting on SMR drives via utilizing the concept of storage-centric computing. Experiments were conducted to demonstrate the capability of the proposed strategy on improving the efficiency of external merge sorting on SMR drives.

통제동사 구문의 국면 삭제 분석

This paper proposes a new analysis of the structure of the Spanish control verb construction in which the matrix verb selects the infinitival clause. Starting from the fact that there is a difference in syntactic phenomena, that is, clitic climbing, between control verb constructions, it turns out to be related to the type of matrix verb. It is argued that both infinitival clause selected by the volitional verb and infinitival clause selected by the non-volitional verb project CP category. I suggest that syntactic difference captured in these two constructions is due to Merge applied in the derivation process. Following Epstein et al.(2016), I assume that internal Merge and external Merge are freely applied. Under the concept of phase cancellation proposed by Chomsky(2015) and Epstein et al.(2016), I argue that C becomes visible in the derivation for infinitival clause selected by non-volitional verb and C becomes invisible in the derivation for infinitival clause selected by volitional verb.

On Wh-elements in Central Kurdish: A Minimalist Approach

The paper sheds light on the status of wh-elements in Central Kurdish (CK) with respect to the framework of the Minimalist Program (MP). From across the globe, there exist various types of languages whose wh-elements behave according to wh-parameter. There are languages whose wh-elements move, some others have in-situ wh-elements, and there are others in which the movement is optional. This paper aims to observe CK wh-elements in an empirical way to indicate their parametric features and their conformance to the universal principles. The notion of movement in MP is included within merge, which falls into two types: Internal merge (I-merge) and External merge (E-merge). Another important term in connection with overt movement is the Extended Projection Principle (EPP) according to which the subject position should be occupied by a phonologically expressed constituent. A fact to be known is that not all languages, among them CK, conform to this principle. The violation of certain CK wh-elements to this principle varies because they do not function in the same way. The paper consists of four sections: introduction, literature review, two basic concepts concerning wh-movement, and an empirical section observing CK wh-elements. It ends with the conclusion and references. One of the conclusions is that CK wh-elements are not considered as one inseparable set since they behave differently.

External Sorting Algorithm: State-of-the-Art and Future Directions

The advent of the era of big data provides new opportunities and more challenges to sorting algorithms. The traditional internal sorting algorithm cannot adapt to the explosive growth of data, and the memory cannot accommodate all the data for sorting, so the external sorting algorithm arises at the historic moment. Because of the different application scenarios, storage devices and improvement strategies, there are many kinds of external sorting algorithms. Traditional main memory architecture based on DRAM faces the problems of capacity, energy consumption and reliability. Emerging nonvolatile memory technologies are non-volatile, high-density, byte-addressable, low-power, so they can replace persistent storage, main memory or storage class memory. Though NVM devices provide new choices to the revolution of traditional memory and storage system, traditional external sorting algorithms cannot achieve its performance. This paper first sorts out the development of external sorting algorithm, and summarizes it into four kinds of external sorting algorithm based on HDD, embedded device, SSD and NVM. In addition, the classical external sorting algorithms based on different storage devices are listed, and our opinions are put forward. Finally, this paper proposes three problems that need to be solved urgently in the future development of external

Exploring Merge: A new form of sideward movement

AbstractThis paper explores Merge and proposes a new form of sideward movement (double sideward movement) carried out by a new application of External Merge. Double sideward movement occurs in the following way: given a syntactic object S containing XP and YP, Merge applies to XP and YP, and creates {XP, YP} outside S, thus causing XP and YP to undergo sideward movement at the same time. It is argued that multiple clefts (cleft sentences with multiple phrases in the focus position) in Japanese are derived by double sideward movement of the multiple focus phrases and that this derivation is responsible for certain surprising properties of Japanese multiple clefts, some well known and others newly discovered, including the lack of island effects and the presence and absence of clausemate effects. Other consequences are discussed for the nature of operator movement and scrambling as well as for restrictions on the application of Merge.

BioSeqZip: a collapser of NGS redundant reads for the optimization of sequence analysis.

MotivationHigh-throughput next-generation sequencing can generate huge sequence files, whose analysis requires alignment algorithms that are typically very demanding in terms of memory and computational resources. This is a significant issue, especially for machines with limited hardware capabilities. As the redundancy of the sequences typically increases with coverage, collapsing such files into compact sets of non-redundant reads has the 2-fold advantage of reducing file size and speeding-up the alignment, avoiding to map the same sequence multiple times.Method BioSeqZip generates compact and sorted lists of alignment-ready non-redundant sequences, keeping track of their occurrences in the raw files as well as of their quality score information. By exploiting a memory-constrained external sorting algorithm, it can be executed on either single- or multi-sample datasets even on computers with medium computational capabilities. On request, it can even re-expand the compacted files to their original state.ResultsOur extensive experiments on RNA-Seq data show that BioSeqZip considerably brings down the computational costs of a standard sequence analysis pipeline, with particular benefits for the alignment procedures that typically have the highest requirements in terms of memory and execution time. In our tests, BioSeqZip was able to compact 2.7 billion of reads into 963 million of unique tags reducing the size of sequence files up to 70% and speeding-up the alignment by 50% at least.Availability and implementation BioSeqZip is available at https://github.com/bioinformatics-polito/BioSeqZip.Supplementary information Supplementary data are available at Bioinformatics online.

A note on the order of constituents in the Mehri Noun Phrase

Abstract Data elicited from native speakers of Mehri and, to a lesser extent, Jibbali—two extant Modern South Arabian languages—show that within the extended nominal phrase, the noun precedes adjectives and the numerals one and two, but follows numerals from three up. This yields the following order: Num≥3 >> Noun >> Num=1,2 >> Adjective. Demonstratives appear between the noun and the numerals one or two, Noun >> Dem >> Num=1,2 >> Adjective, but when the noun is preceded by numerals from three up, the order is Dem >> Num≥3 >> Noun >> Adjective. Following Cinque (2005), I argue that these orders can be explained by taking the constituent order derived by external merge to be Dem >> Num≥3 >> Num=1,2 >> Adjective >> Noun and having the noun (more precisely, the minimal noun phrase) move step-by-step to a position immediately above, and therefore to the left of Num=1,2. The noun cannot move above Num≥3 and since it cannot skip it, it also remains below Dem.

Performance Analysis of a Faster In−place External Sorting Algorithm

Data sets in large applications are often too gigantic to fit completely inside the computer’s internal memory. The resulting input/output communication (or I/O) between fast internal memory and slower external memory (such as disks) can be a major performance bottle−neck. While applying sorting on this huge data set, it is essential to do external sorting. This paper is concerned with a new in−place external sorting algorithm. Our proposed algorithm uses the concept of Quick−Sort and Divide−and−Conquer approaches resulting in a faster sorting algorithm avoiding any additional disk space. In addition, we showed that the average time complexity can be reduced compared to the existing external sorting approaches.

Efficient and Scalable External Sort Framework for NVMe SSD

As the size of data grows in modern applications, the efficient usage of limited resources is becoming crucial. In order to reorganize large data under memory limitations, many data-intensive applications utilize external sort as a critical component. To streamline external sort, a storage framework is especially needed since the entire dataset must be loaded and flushed a couple of times during the sorting process. Most existing frameworks have attempted to simplify the storage access pattern by associating each thread with a separate storage device. This prevents randomized and concurrent I/O requests, which impose a huge overhead for legacy drives in order to enable the parallelism needed for external sort. However, such regulations excessively restrain the capabilities of NVMe-based SSDs that deliver high throughput with abundant parallelism. In this article, we present a new framework for external sort that exploits both external and internal parallelism. Externally, any number of threads are mobilized to parallel external sort in a scalable way, even with one NVMe SSD. Meanwhile, some arbitration schemes, such as adaptive resource allocation and fairness control, are adopted to preserve the internal efficiency of storage devices. Our evaluation results demonstrate that our scheme can greatly improve both the I/O efficiency and scalability compared to the existing frameworks.

Scalable energy-efficient parallel sorting on a fine-grained many-core processor array

Three parallel sorting applications and two list output protocols for the first phase of an external sort execute on a fine-grained many-core processor array that contains no algorithm-specific hardware acting as a co-processor with a variety of array sizes. Results are generated using a cycle-accurate model based on measured data from a fabricated many-core chip, and simulated for different processor array sizes. The data shows most energy efficient first-phase many-core sort requires over 65× lower energy than GNU C++ standard library sort performed on an Intel laptop-class processor and over 105× lower energy than a radix sort running on an Nvidia GPU. In addition, the highest first-phase throughput many-core sort is over 9.8× faster than the std::sort and over 14× faster than the radix sort. Both phases of a 10 GB external sort require 6.2× lower energy×time energy delay product than the std::sort and over 13× lower energy×time than the radix sort.

Problemes de «Problemes de projecció». Trencar un empat conceptual

El model d’etiquetatge exocentric de Chomsky (2013, 2015), Problemes de projeccio, fa que la projeccio sigui mes problematica que abans i que doni lloc a nombroses complicacions tecniques i conceptuals, redundancies i incoherencies. Es particularment preocupant la reversibilitat de les hipotesis que es fan respecte de la relacio entre l’etiquetatge i la cerca, de manera que la teoria contraria es igualment coherent i proporciona els mateixos resultats empirics. Despres de revisar aquestes preocupacions, es dibuixa una concepcio mes senzilla de l’etiquetatge exocentric en que totes les etiquetes s’afegeixen uniformement mitjancant la fusio externa de nuclis de fase categoritzadors, que converteixen objectes sintactics no marcats (sense interpretar) en fases etiquetades (interpretades). Es consideren finalment alguns avantatges conceptuals i empirics del sistema mes senzill.

Biologically Based Merge of Wh-questions in the Bamboo Slips of Tao Te Ching

The bamboo slips of Tao Te Ching is the earliest found version of the ancient Chinese classic philosophical work written by Li Er in the Spring Warring State Era. The merger operation of the wh-questions in the bamboo slips of Tao Te Ching is dealt with in this thesis. External merge of the wh-words is contrasted with the internal merge of wh-words in wh-questions and non-wh-words in topic structures of wh-questions in the bamboo slips of Tao Te Ching. The biologically localized merger is further discussed and proven by the experiment on the aphasic patients of the biscuits stolen story.

Toward a new approach for sorting extremely large data files in the big data era

The extensive amount of data and contents generated today will require a paradigm shift in processing and management techniques for these data. One of the important data processing operations is the data sorting. Using multiple passes in external merge sort has a great influence on speeding up the sorting of extremely large data files. Since in large files, the swapping time is dominant in many applications, algorithms that minimize the swapping operations are normally superior to those which only focus on CPU time optimizations. In sorting extremely large files, external algorithms, such as the merge sort, are normally used. It is shown that using multiple passes over the data set, as proposed in our algorithm, has resulted in a great improvement in the number of swaps, thus, reducing the overall sorting time. Moreover, the proposed technique is suitable to be used with the emerging parallelization techniques such as GPUs. The reported results show the superiority of the proposed technique for “CPU only” and hybrid CPU–GPU implementations.

Duplicity in possessive merger: evidence from Spanish alienable possessive constructions

AbstractIn this paper, I argue that Spanish prenominal and postnominal possessives target different external merge positions focusing on alienable possessive constructions. The analysis is developed alongside a proposal on the organization of DPs, according to which articles are merged as a DP-internal category between the domains assigned to direct and indirect modifiers. Prenominal possessives are determiners reanalyzed from direct modification adjectives whereas postnominal possessives are indirect modification adjectives that arise as predicates of reduced relative clauses. This analysis provides a principled explanation on the behavior of Spanish possessives that is lacking in the generalized idea that they are pronouns with a unique merge position. Arguments are also presented showing that syntax-driven phonological restrictions condition the derivation of DPs. The account successfully derives the core properties of word order variation and related issues within possessive constructions.

A Restriction on Recursion

AbstractUniversal Grammar places a restriction on self‐embedding recursion structures created through External Merge: A phasal category of type α can be embedded in a phasal category of the same type where there is a c‐command relation between the heads of the two instances of α only if the two instances of α are separated by a phase head. This restriction (the exact counterpart of the familiar c‐command cum phasemate requirement that is imposed on identical copies of a single category under Internal Merge) explains a variety of hitherto poorly understood properties of the noun phrase. The set of elements that are eligible to serve as nondative possessors in Hungarian possessive DPs is shown to fall out from the recursion restriction: all and only those possessors that are not as large as DP can be placed in the caseless possessor position in the immediate c‐command domain of the D head of the possessive noun phrase; dative possessors are in the specifier position of the possessive DP, not c‐commanded by its D head and hence immune to the recursion restriction. The recursion restriction sheds new light on the syntax of the possessive noun phrase, the nature of possessor drop, and the structure and distribution of demonstratives. The analysis also presents an empirical case for labeling of XP–YP structures via ϕ‐feature sharing.

MONTRES : Merge ON-the-Run External Sorting Algorithm for Large Data Volumes on SSD Based Storage Systems

External sorting algorithms are commonly used by data-centric applications to sort quantities of data that are larger than the main-memory. Many external sorting algorithms were proposed in state-of-the-art studies to take advantage of SSD performance properties to accelerate the sorting process. In this paper, we demonstrate that unfortunately, many of those algorithms fail to scale when it comes to increasing the dataset size under memory pressure. In order to address this issue, we propose a new sorting algorithm named MONTRES. MONTRES relies on SSD performance model while decreasing the overall number of I/O operations. It does this by reducing the amount of temporary data generated during the sorting process by continuously evicting small values in the final sorted file. MONTRES scales well with growing datasets under memory pressure. We tested MONTRES using several data distributions, different amounts of main-memory workspace and three SSD models. Results showed that MONTRES outperforms state-of-the-art algorithms as it reduces the sorting execution time of TPC-H datasets by more than 30 percent when the file size to main-memory size ratio is high.

Variation in the pronunciation/silence of the prepositions in locative determiners

We argue that the micro-variation observed in the pronunciation/silence of the prepositional head of locative determiners in Fallese, a dialect spoken in Abruzzi, follows from the option of valuing features by either External Merge or by Internal Merge, given Spell-Out conditions, whereas this option is not available in English and Italian. It follows that the prepositional head is silent in Italian and English, whereas it can be pronounced in Fallese when the Specifier of the locative determiner is not filled. We show that this feature-based approach to micro-variation, in conjunction with principles of efficient computation, makes correct predictions for the pronunciation of the prepositional head in other functional categories, as well as it makes predictions on the diachronic development of locative determiners Latin to Fallese and from Latin to Italian’, otherwise it looks like Fallese is an old stage of Italian.

Optimization of SAMtools sorting using OpenMP tasks

SAMtools is a widely-used genomics application for post-processing high-throughput sequence alignment data. Such sequence alignment data are commonly sorted to make downstream analysis more efficient. However, this sorting process itself can be computationally- and I/O-intensive: high-throughput sequence alignment files in the de facto standard binary alignment/map (BAM) format can be many gigabytes in size, and may need to be decompressed before sorting and compressed afterwards. As a result, BAM-file sorting can be a bottleneck in genomics workflows. This paper describes a case study on the performance analysis and optimization of SAMtools for sorting large BAM files. OpenMP task parallelism and memory optimization techniques resulted in a speedup of 5.9X versus the upstream SAMtools 1.3.1 for an internal (in-memory) sort of 24.6 GiB of compressed BAM data (102.6 GiB uncompressed) with 32 processor cores, while a 1.98X speedup was achieved for an external (out-of-core) sort of a 271.4 GiB BAM file.

A source of parametric variation in the lexicon

An influential conjecture concerning parameters is that they can possibly be “restricted to formal features of functional categories” (Chomsky 1995: 6). In Rizzi (2009, 2011) such features are understood as instructions triggering one of the following syntactic actions: (1) External Merge; (2) Internal Merge (Move); (3) Pronunciation/Non pronunciation (the latter arguably dependent on Internal Merge – Kayne 2005a, b). In this article I consider a particular source of parametric variation across languages in the domain of the lexicon (both functional and substantive) which appears to be due to the possibility of underspecifying certain features in some languages. The paradigmatic variation can be characterized as follows: language A has two (or more) lexical items which correspond to just one lexical item in language B.