IT Lightning Talks: session #2

Python code is much easier to write than C, yet much less efficient. It's often assumed that Python is not performance-oriented and therefore making effort to optimize it doesn't pay off. While in many cases it's true, at a certain moment of a development, especially right before reaching production-ready state, it might turn out that a Python code runs slowly and one needs to find a culprit. In this talk I'll not tell how to make your program faster. Instead, I'll show different techniques to look for the bottlenecks in the code. The presentation will be built around a live demo using real-life Python code

Data Centre Technology and Market Trends

In this ITTF session we will provide an overview of data center technologies and market trends in the fields of server processors, memory architectures, server platforms, storage technology (both solid state and spinning media), Intel future roadmaps, Open Compute Project hardware and server-side networking. We will begin with a peek into the evolution of processors over the last 40+ years and provide an outlook into future processor trends. The highlights of the most recent Intel server processor generation (Xeon E5-2600 v3, Haswell-EP) will be presented together with the specifics of the new generation of DDR memory technology employed. Alternative processor architectures from contenders like ARM Holdings (with their AArch64 architecture) and IBM (with their OpenPOWER initiative) will be discussed. An overview of existing enterprise solid state technology will be given, showing the kind of performance provided by the currently available enterprise SSD drives and future directions for non volatile memory based storage devices. We will continue with an overview of the enterprise spinning disk market. The techniques used by the hard drive manufacturers to satisfy the demand for ever growing capacities per spindle will be described. Finally, an analysis suggesting which type of drive(s) best fit our applications will be presented. The presentation will also include Intel's plans for expansions in the computing hardware: new Skylake microarchitecture, Omni-Path interconnect, non-volatile main memory, Intel Transactional Extension and Rack-scale architecture. It will also cover broadly the next generations of Intel co-processors: Knights Landing and Knights Hill. The Open Compute Project, OCP (http://www.opencompute.org), was launched by Facebook in 2011 with the objective of building efficient computing infrastructures at the lowest possible cost. After an initial evaluation of two OCP twin server enclosures in 2013, we decided to launch a tender for acquiring OCP compliant hardware comprising both CPU servers and storage. We will introduce the OCP designs currently available on the market, the advantages they provide and how OCP could fit with CERN's computing and storage needs in the future. We will finish by showing the current status of the server-side networking in the CERN Data Center, followed by an overview of the market trends and future changes for server networking

CeON/CERMINE: CERMINE 1.13

Content ExtRactor and MINE

Second asymptomatic carotid surgery trial (ACST-2) : a randomised comparison of carotid artery stenting versus carotid endarterectomy

Background: Among asymptomatic patients with severe carotid artery stenosis but no recent stroke or transient cerebral ischaemia, either carotid artery stenting (CAS) or carotid endarterectomy (CEA) can restore patency and reduce long-term stroke risks. However, from recent national registry data, each option causes about 1% procedural risk of disabling stroke or death. Comparison of their long-term protective effects requires large-scale randomised evidence. Methods: ACST-2 is an international multicentre randomised trial of CAS versus CEA among asymptomatic patients with severe stenosis thought to require intervention, interpreted with all other relevant trials. Patients were eligible if they had severe unilateral or bilateral carotid artery stenosis and both doctor and patient agreed that a carotid procedure should be undertaken, but they were substantially uncertain which one to choose. Patients were randomly allocated to CAS or CEA and followed up at 1 month and then annually, for a mean 5 years. Procedural events were those within 30 days of the intervention. Intention-to-treat analyses are provided. Analyses including procedural hazards use tabular methods. Analyses and meta-analyses of non-procedural strokes use Kaplan-Meier and log-rank methods. The trial is registered with the ISRCTN registry, ISRCTN21144362. Findings: Between Jan 15, 2008, and Dec 31, 2020, 3625 patients in 130 centres were randomly allocated, 1811 to CAS and 1814 to CEA, with good compliance, good medical therapy and a mean 5 years of follow-up. Overall, 1% had disabling stroke or death procedurally (15 allocated to CAS and 18 to CEA) and 2% had non-disabling procedural stroke (48 allocated to CAS and 29 to CEA). Kaplan-Meier estimates of 5-year non-procedural stroke were 2·5% in each group for fatal or disabling stroke, and 5·3% with CAS versus 4·5% with CEA for any stroke (rate ratio [RR] 1·16, 95% CI 0·86-1·57; p=0·33). Combining RRs for any non-procedural stroke in all CAS versus CEA trials, the RR was similar in symptomatic and asymptomatic patients (overall RR 1·11, 95% CI 0·91-1·32; p=0·21). Interpretation: Serious complications are similarly uncommon after competent CAS and CEA, and the long-term effects of these two carotid artery procedures on fatal or disabling stroke are comparable