142 research outputs found
The Trigger and Data Acquisition System for the 8 tower subsystem of the KM3NeT detector
No full textKM3NeT is a deep-sea research infrastructure being constructed in the Mediterranean Sea. It will host a large Cherenkov neutrino telescope that will collect photons emitted along the path of the charged particles produced in neutrino interactions in the vicinity of the detector. The philosophy of the DAQ system of the detector foresees that all data are sent to shore after a proper sampling of the photomultiplier signals. No off-shore hardware trigger is implemented and a software selection of the data is performed with an on-line Trigger and Data Acquisition System (TriDAS) to reduce the large throughput due to the environmental light background. A first version of the TriDAS has been developed to operate a prototype detection unit deployed in March 2013 in the abyssal site of Capo Passero (Sicily, Italy), about 3500 m deep. A revised and improved version has been developed to meet the requirements of the final detector, using new tools and modern design solutions. First installation and scalability tests have been performed at the Bologna Common Infrastructure and results comparable to what expected have been observed
The Trigger and Data Acquisition System for the KM3NeT-Italia towers
No full textKM3NeT-Italia is an INFN project supported with Italian PON fundings for building the core of the Italian node of the KM3NeT neutrino telescope. The detector, made of 700 10′′ Optical Modules (OMs) lodged along 8 vertical structures called towers, will be deployed starting from fall 2015 at the KM3NeT-Italy site, about 80 km off Capo Passero, Italy, 3500 m deep. The all data to shore approach is used to reduce the complexity of the submarine detector, demanding for an on-line trigger integrated in the data acquisition system running in the shore station, called TriDAS. Due to the large optical background in the sea from 40K decays and bioluminescence, the throughput from the underwater detector can range up to 30 Gbps. This puts strong constraints on the design and performances of the TriDAS and of the related network infrastructure. In this contribution the technology behind the implementation of the TriDAS infrastructure is reviewed, focusing on the relationship between the various components and their performances. The modular design of the TriDAS, which allows for its scalability up to a larger detector than the 8-tower configuration is also discussed
The Trigger and Data Acquisition System for the KM3NeT-Italy neutrino telescope
No full textKM3NeT-Italy is an INFN project that will develop the central part of a submarine cubic-kilometer neutrino telescope in the Ionian Sea, at about 80 km from the Sicilian coast (Italy). It will use hundreds of distributed optical modules to measure the Cherenkov light emitted by high-energy muons, whose signal-to-noise ratio is quite disfavoured. In this contribution the Trigger and Data Acquisition System (TriDAS) developed for the KM3NeT-Italy detector is presented. The "all data to shore" approach is adopted to reduce the complexity of the submarine detector: at the shore station the TriDAS collects, processes and filters all the data coming from the detector, storing triggered events to a permanent storage for subsequent analysis. Due to the large optical background in the sea from 40K decays and bioluminescence, the throughput from the sea can range up to 30 Gbps. This puts strong constraints on the performances of the TriDAS processes and the related network infrastructure
The 40 MHz trigger-less DAQ for the LHCb Upgrade
No full textThe LHCb experiment will undergo a major upgrade during the second long shutdown (2018–2019), aiming to let LHCb collect an order of magnitude more data with respect to Run 1 and Run 2. The maximum readout rate of 1 MHz is the main limitation of the present LHCb trigger. The upgraded detector, apart from major detector upgrades, foresees a full read-out, running at the LHC bunch crossing frequency of 40 MHz, using an entirely software based trigger
Flit-Level InfiniBand Network Simulations of the DAQ System of the LHCb Experiment for Run-3
No full textThe Large Hadron Collider beauty (LHCb) experiment is designed to study the differences between particles and antiparticles as well as very rare decays in the charm and beauty sector at the (LHC). The detector will be upgraded in 2019, and a new trigger-less readout system will be implemented in order to significantly increase its efficiency and fully take advantage of the provided machine luminosity at the LHCb collision point. In the upgraded system, both event building and event filtering will be performed in software for all the data produced in every bunch-crossing of the LHC. In order to transport the full data rate of 32 Tb/s, we will use custom field-programmable gate array (FPGA) readout boards (PCIe40) and the state-of-the-art off-the-shelf network technologies. The full-event-building system will require around 500 servers interconnected together. From a networking point of view, event building traffic has an all-to-all pattern, requiring careful design of the network architecture to avoid congestion at the data rates foreseen. In order to maximize link utilization, different techniques can be adopted in various areas like traffic shaping, network topology, and routing optimization. The size of the system makes it very difficult to test at production scale, before the actual procurement. We resort, therefore, to network simulations as a powerful tool for finding the optimal configuration. We will present an accurate low-level description of an InfiniBand-based network with event building like traffic. We will show a comparison between simulated and reduced scale systems and how changes in the input parameters affect the performance
Computing on Knights and Kepler Architectures
No full textA recent trend in scientific computing is the increasingly important role of co-processors, originally built to accelerate graphics rendering, and now used for general high-performance computing. The INFN Computing On Knights and Kepler Architectures (COKA) project focuses on assessing the suitability of co-processor boards for scientific computing in a wide range of physics applications, and on studying the best programming methodologies for these systems. Here we present in a comparative way our results in porting a Lattice Boltzmann code on two state-of-the-art accelerators: the NVIDIA K20X, and the Intel Xeon-Phi. We describe our implementations, analyze results and compare with a baseline architecture adopting Intel Sandy Bridge CPUs
Exploiting new CPU architectures in the SuperB software framework
No full textThe SuperB asymmetric-energy e+e- collider and detector to be built at the newly founded Nicola Cabibbo Lab will provide a uniquely sensitive probe of New Physics in the flavour sector of the Standard Model. Studying minute effects in the heavy quark and heavy lepton sectors requires a data sample of 75ab-1 and a luminosity target of 10 36cm-2s-1. These parameters require a substantial growth in computing requirements and performances. The SuperB collaboration is thus investigating the advantages of new CPU architectures (multi and many cores) and how to exploit their capability of task parallelization in the framework for simulation and analysis software. In this work we present the underlying architecture which we intend to use and some preliminary performance results of the first framework prototype
High throughput data acquisition with InfiniBand on x86 low-power architectures for the LHCb upgrade
No full textThe LHCb Collaboration is preparing a major upgrade of the detector and the Data Acquisition (DAQ) to be installed during the LHC-LS2. The new Event Builder computing farm for the DAQ requires about 500 nodes, and have to be capable of transporting order of 32 Tbps. The requested performance can possibly be achieved using high-bandwidth data-centre switches and commodity hardware. Several studies are ongoing to evaluate and compare network and hardware technologies, with the aim of optimising the performance and also the purchase and maintenance costs of the system. We are investigating if x86 low-power architectures can achieve equivalent performance as traditional servers when used for multi gigabit DAQ. In this talk we introduce an Event Builder implementation based on InfiniBand network and show preliminary tests with this network technology on x86 low-power architectures, such as Intel Atom C2750 and Intel Xeon D-1540, comparing measured bandwidth and power consumption
An integrated infrastructure in support of software development
No full textThis paper describes the design and the current state of implementation of an infrastructure made available to software developers within the Italian National Institute for Nuclear Physics (INFN) to support and facilitate their daily activity. The infrastructure integrates several tools, each providing a well-identified function: project management, version control system, continuous integration, dynamic provisioning of virtual machines, efficiency improvement, knowledge base. When applicable, access to the services is based on the INFN-wide Authentication and Authorization Infrastructure. The system is being installed and progressively made available to INFN users belonging to tens of sites and laboratories and will represent a solid foundation for the software development efforts of the many experiments and projects that see the involvement of the Institute. The infrastructure will be beneficial especially for small- and medium-size collaborations, which often cannot afford the resources, in particular in terms of know-how, needed to set up such services. © Published under licence by IOP Publishing Ltd
BESIII and SuperB: distributed job management with Ganga
No full textA job submission and management tool is one of the necessary components in any distributed computing system. Such a tool should provide a user-friendly interface for physics production groups and ordinary analysis users to access heterogeneous computing resources, without requiring knowledge of the underlying grid middleware. Ganga, with its common framework and customizable plug-in structure is such a tool. This paper will describe how experiment-specific job management tools for BESIII and SuperB were developed as Ganga plug-ins to meet their own unique requirements, discuss and contrast their challenges met and lessons learned
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