Conveners
T5 - Software development: S1
- Patricia Mendez Lorenzo (CERN)
T5 - Software development: S2
- Barthelemy Von Haller (CERN)
T5 - Software development: S3 - Concurrency
- Barthelemy Von Haller (CERN)
T5 - Software development: S4 - Frameworks
- Patricia Mendez Lorenzo (CERN)
T5 - Software development: S5.1 Interactive Frameworks
- Maiken Pedersen (University of Oslo (NO))
T5 - Software development: S5.2 - Software Packaging, Build Systems - Part 1
- Maiken Pedersen (University of Oslo (NO))
T5 - Software development: S6.1 - Software Packaging, Build Systems - Part 2
- Maiken Pedersen (University of Oslo (NO))
T5 - Software development: S6.2 - Continuous Integration
- Maiken Pedersen (University of Oslo (NO))
T5 - Software development: S7 - Performance, Profiling, Code Optimization
- Patricia Mendez Lorenzo (CERN)
ALFA is a message queuing based framework for online and offline data processing. It is a flexible framework that supports an actor based computational model and allows to implement an experiment defined data model on top. The design of ALFA is modular with separate layers for data transport, process management and process deployment. Although still under ongoing development, ALFA is already...
The ALICE experiment at the LHC (CERN) is currently developing a new software framework designed for Run 3: detector and software will have to cope with Pb-Pb collision rates 100 times higher than today, leading to the combination of core Online-Offline operations into a single framework called O².
The analysis code is expected to run on a few large Analysis Facilities counting 20k cores and...
Weak gravitational lensing is an extremely powerful probe for gaining insight into the nature of two of the greatest mysteries of the universe -- dark energy and dark matter. To help prepare for the massive amounts of data coming from next generation surveys like LSST that hope to advance our understanding of these mysteries, we have developed an automated and seamless weak lensing cosmic...
The software for detector simulation, reconstruction and analysis of physics data is an essential part of each high-energy physics experiment. A new generation of the experiments for the relativistic nuclear physics is expected to be started up in the nearest years at the Nuclotron-based Ion Collider facility (NICA) being under construction at the Joint Institute for Nuclear Research in Dubna:...
Technical details of the directly manipulated systems and the impact on non-obviously connected systems are required knowledge when preparing an intervention in a complex experiment like ATLAS. In order to improve the understanding of the parties involved in an intervention a rule-based expert system has been developed. On the one hand this helps to recognize dependencies that are not always...
AMI (ATLAS Metadata Interface) is a generic ecosystem for metadata aggregation, transformation and cataloguing. Benefitting from more than 15 years of feedback in the LHC context, the second major version was recently released. We describe the design choices and their benefits for providing high-level metadata-dedicated features. In particular, we focus on the implementation of the Metadata...
In spite of the fact that HEP computing has evolved considerably over the years, the understanding of the evolution process seems to be still incomplete. There is no clear procedure to replace an established product with a new one, and most of the successful major transitions (e.g. PAW to Root or Geant3 to Geant4) have involved a large dose of serendipity and have caused splits in the...
The need for good software training is essential in the HEP community. Unfortunately, current training is non-homogeneous and the definition of a common baseline is unclear, making it difficult for newcomers to proficiently join large collaborations such as ALICE or LHCb.
In the last years, both collaborations have started separate efforts to tackle this issue through training workshops, via...
In order to meet the challenges of the Run-3 data rates and volumes, the ALICE collaboration is merging the online and offline infrastructures into a common framework: ALICE-O2.
O2 is based on FairRoot and FairMQ, a message-based, multi-threaded and multi-process control framework.
In FairMQ, processes (possibly on different machines) exchange data via message queues either through 0MQ or...
Collaboration in research is essential for it is saving time and money. The field of high-energy physics (HEP) is no different. The higher level of collaboration the stronger community. The HEP field encourages organizing various events in format and size such as meetings, workshops and conferences. Making attending a HEP event easier leverages cooperation and dialogue and this is what makes...
Indico is a general-purpose event management system currently in use by more than 150 institutions world wide. Despite having been born at CERN and primarily adopted by the High Energy Physics Community, it has recently gained adoption in other communities (for example, the United Nations and its agencies) and received the attention of commercial vendors world wide. This growth in adoption...
The ROOT software framework is foundational for the HEP ecosystem, providing capabilities such as IO, a C++ interpreter, GUI, and math libraries. It uses object-oriented concepts and build-time modules to layer between components. We believe additional layering formalisms will benefit ROOT and its users.
We present the modularization strategy for ROOT which aims to formalize the description...
The GooFit highly parallel fitting package for GPUs and CPUs has been substantially upgraded in the past year. Python bindings have been added to allow simple access to the fitting configuration, setup, and execution. A Python tool to write custom GooFit code given a (compact and elegant) MINT3/AmpGen amplitude description allows the corresponding C++ code to be written quickly and correctly. ...
In order to take full advantage of new computer architectures and to satisfy the requirement of minimising the CPU usage with increasing amount of data to analysis, parallelisation and SIMD vectorisation have been introduced in the ROOT mathematical libraries. The VecCore library provides a very convenient solution to abstract SIMD vectorization and it has been found extremely useful for...
Scalable multithreading poses challenges to I/O, and the performance of a thread-safe I/O strategy
may depend upon many factors, including I/O latencies, whether tasks are CPU- or I/O-intensive, and thread count.
In a multithreaded framework, an I/O infrastructure must efficiently supply event data to and collect it from many threads processing multiple events in flight.
In particular,...
Hydra is a templatized header-only, C++11-compliant library for data analysis on massively parallel platforms targeting, but not limited to, the field High Energy Physics research.
Hydra supports the description of particle decays via the generation of phase-space Monte Carlo, generic function evaluation, data fitting, multidimensional adaptive numerical integration and histograming.
Hydra is...
In the coming years, HEP data processing will need to exploit parallelism on present and future hardware resources to sustain the bandwidth requirements.
As one of the cornerstones of the HEP software ecosystem, ROOT embraced an ambitious parallelisation plan which delivered compelling results.
In this contribution the strategy is characterised as well as its evolution in the medium term.
The...
Since the beginning of the LHC Run 2 in 2016 the CMS data processing framework, CMSSW, has been running with multiple threads during production of data and simulation via the use of Intel's Thread Building Blocks (TBB) library. The TBB library utilizes tasks as concurrent units of work. CMS used these tasks to allow both concurrent processing of events as well as concurrent running of modules...
The LHC experiments produce tens of petabytes of new data in ROOT format per year that need to be processed and analysed. In the next decade, following the planned upgrades of the LHC and the detectors, this rate is expected to increase at least ten-fold.
Therefore, optimizing the ROOT I/O subsystem is of critical importance to the success of the LHC physics programme. This contribution...
In high energy physics experiments, silicon detectors are often subjected to a harsh radiation environment, specially at hadronic colliders. Understanding the impact of radiation damage on the detector performance is an indispensable prerequisite for a successful operation throughout the lifetime of the planned experiment.
A dedicated irradiation programme followed by detailed studies with...
The LHCb detector will be upgraded for the LHC Run 3. The new, full software trigger must be able to sustain the 30MHz proton-proton inelastic collision rate. The Gaudi framework currently used in LHCb has been re-engineered in order to enable the efficient usage of vector registers and of multi- and many-core architectures. This contribution presents the critical points that had to be...
ALICE is one of the four major LHC experiments at CERN. When the accelerator enters the Run 3 data-taking period, starting in 2021, ALICE expects almost 100 times more Pb-Pb central collisions than now, resulting in a large increase of data throughput. In order to cope with this new challenge, the collaboration had to extensively rethink the whole data processing chain, with a tighter...
In preparation for Run 3 of the LHC, scheduled to start in 2021, the ATLAS
experiment is revising its offline software so as to better take advantage
of machines with many cores. A major part of this effort is migrating the
software to run as a fully multithreaded application, as this has been
shown to significantly improve the memory scaling behavior. This talk will
outline changes made to...
Measurement of the physical parameters is usually done by fitting a numerical experiment model to the data. High precision experiments require detailed models with a large number of uncertain parameters. The models should be computationally efficient. In the same time they should be flexible enough since the analysis preparation requires a lot of testing.
We are solving these problems by...
In this paper, we present micro-services framework to develop data processing applications.
We discuss functional decomposition strategies that help transitioning of existing data processing applications into a micro-services environment. We will also demonstrate advantages and disadvantages of this framework in terms of operational elasticity, vertical and horizontal scalability,...
Data quality monitoring is the first step to the certification of the recorded data for off-line physics analysis. Dedicated monitoring framework have been developed by many experiments in the past and usually rely on the event data model (EDM) of the experiment, leading to a strong dependency on the data format and storage. We present here a generic data quality monitoring system, DQM4HEP,...
The Cherenkov Telescope Array (CTA), currently under construction, is the next- generation instrument in the field of very high energy gamma-ray astronomy. The first data are expected by the end of 2018, while the scientific operations will start in 2022 for a duration of about 30 years. In order to characterise the instrument response to the Cherenkov light emitted by atmospheric cosmic ray...
Numerical stability is not only critical to the correctness of scientific computations, but also has a direct impact on their software efficiency as it affects the convergence of iterative methods and the available choices of floating-point precision.
Verrou is a Valgrind-based tool which challenges the stability of floating-point code by injecting random rounding errors in computations (a...
For two decades, ROOT brought its own window system abstraction (for X11, GL, Cocoa, and Windows) together with its own GUI library. X11 is nearing the end of its lifetime; new windowing systems shine with performance and features. To make best use of them, the ROOT team has decided to re-implement its graphics and GUI subsystem using web technology.
This presentation introduces the model,...
The divergence of windowing systems among modern Linux distributions and OSX is making the current mode of operations difficult to maintain. In order to continue support the CMS experiment event display, aka Fireworks, we need to explore other options beyond the current distribution model of centrally built tarballs.
We think that C++-server web-client event display is a promising direction...
The process of building software for High Energy Physics is a problem that all experiments must face. It is also an aspect of the technical management of HEP software that is highly suited to sharing knowledge and tools. For this reason the HEP Software Foundation established a working group in 2015 to look at packaging and deployment solutions in the HEP community. The group has examined in...
Since its inception in 2010, the art event-based analysis framework and associated software have been delivered to client experiments using a Fermilab-originated system called UPS. Salient features valued by the community include installation without administration privileges, trivially-relocatable binary packages and the ability to use coherent sets of packages together (such as those...
IceCube is a cubic kilometer neutrino detector located at the south pole. CVMFS is a key component to IceCube’s Distributed High Throughput Computing analytics workflow for sharing 500GB of software across datacenters worldwide. Building the IceCube software suite on CVMFS has historically been accomplished first by a long bash script, then by a more complex set of python scripts. We...
For over a decade, dCache.org has provided software which is used at more than 80 sites around the world, providing reliable services for WLCG experiments and others. This can be achieved only with a well established process starting from the whiteboard, where ideas are created, all the way through to packages, installed on the production systems. Since early 2013 we have moved to git as our...
Building, testing and deploying of coherent large software stacks is very challenging, in particular when they consist of the diverse set of packages required by the LHC experiments, the CERN Beams department and data analysis services such as SWAN. These software stacks include several packages (Grid middleware,Monte Carlo generators, Machine Learning tools, Python modules) all required for...
Complex, large-scale distributed systems are more frequently used to solve
extraordinary computing, storage and other problems. However, the development
of these systems usually requires working with several software components,
maintaining and improving large codebases, and also a relatively large number
of developers working together. Therefore, it is inevitable to introduce faults
to the...
The data processing of HEP data relies on rich software distributions, made of experiment specific software and hundreds of other software products, developed by our community and outside it.
This kind of software stacks are traditionally distributed on shared file systems as a set of packages coherently built. This has the benefit of reducing as much as possible any coupling with the...
The LHCb physics software has to support the analysis of data taken up to now and at the same time is under active development in preparation for the detector upgrade coming into operation in 2021. A continuous integration system is therefore crucial to maintain the quality of the ~6 millions of lines of C++ and Python, to ensure consistent builds of the software as well as to run the unit and...
The LHCb Performance Regression (LHCbPR) framework allows for periodic software testing to be performed in a reproducible manner.
LHCbPR provides a JavaScript based web front-end service, built atop industry standard tools such as AngularJS, Bootstrap and Django (https://lblhcbpr.cern.ch).
This framework records the evolution of tests over time allowing for this data to be extracted for...
This paper describes the current architecture of Continuous Integration (CI) service developed at Fermilab, encountered successes and difficulties, as well as future development plans. Current experiment code has hundreds of contributors that provide new features, bug fixes, and other improvements. Version control systems help developers to collaborate in contributing software for their...
MERLIN is a C++ particle tracking software package, originally developed at DESY for use in International Linear Collider (ILC) simulations. MERLIN has more recently been adapted for High-Luminosity Large Hadron Collider (HL-LHC) collimation studies, utilising more advanced scattering physics. However, as is all too common in existing high-energy physics software, recent developments have not...
Software quality monitoring and analysis is one of the most productive topics of software engineering research. Their results may be employed effectively by engineers during software development life cycle. Software metrics, together with data mining techniques, can provide the basis for developing prediction models.
Open source software constitutes a valid test case for the assessment of...
LHCb is undergoing major changes in its data selection and processing chain for the upcoming LHC Run 3 starting in 2021. With this in view several initiatives have been launched to optimise the software stack. This contribution discusses porting the LHCb Stack from x86 architecture to aarch64 architecture with the goal to evaluate the performance and the cost of the computing infrastructure...
Analysis of neutrino oscillation data involves a combination of complex fitting procedures and statistical corrections techniques that are used to determine the full three-flavor PMNS parameters and constraint contours. These techniques rely on computationally intensive “multi-universe” stochastic modeling. The process of calculating these contours and corrections can dominate final stages...
SNiPER is a general purpose offline software framework for high energy physics experiment. It provides some features that is attractive to neutrino experiments, such as the event buffer. More than one events are available in the buffer according to a customizable time window, so that it is easy for users to apply events correlation analysis.
We also implemented the MT-SNiPER to support...
In many HEP experiments a typical data analysis workflow requires each user
to read the experiment data in order to extract meaningful information and produce relevant plots for the considered analysis. Multiple users accessing the same data result in a redundant access to the data itself, which could be factorised effectively improving the CPU efficiency of the analysis jobs and relieving...
