Reverse engineering Swisscom's Centro Grande Modem

Spencer Christensen There are many aspects to managing an RDBMS. Some of these are handled by an experienced DBA, but there are a good many things that any sys admin should be able to take care of if they know what to look for. This presentation will cover basics of managing Postgres, including creating database clusters, overview of configuration, and logging. We will also look at tools to help monitor Postgres and keep an eye on what is going on. Some of the tools we will review are: * pgtop * pg_top * pgfouine * check_postgres.pl. Check_postgres.pl is a great tool that can plug into your Nagios or Cacti monitoring systems, giving you even better visibility into your databases.

This document discusses how Qemu works to translate guest binaries to run on the host machine. It first generates an intermediate representation called TCG-IR from the guest binary code. It then translates the TCG-IR into native host machine code. To achieve high performance, it chains translated blocks together by patching jump targets. Key techniques include just-in-time compilation, translation block finding, block chaining, and helper functions to emulate unsupported guest instructions.

The pg_stat_monitor is the statistics collection tool based on PostgreSQL’s contrib module pg_stat_statements. PostgreSQL’s pg_stat_statements provides only basic statistics, which is sometimes not enough. The major shortcoming in pg_stat_statements is that it accumulates all the queries and statistics, but does not provide aggregated statistics or histogram information. In this case, a user needs to calculate the aggregate, which is quite expensive. Pg_stat_monitor provides the pre-calculated aggregates. pg_stat_monitor collects and aggregates data on a bucket basis. The size and number of buckets should be configured using GUC (Grand Unified Configuration). The buckets are used to collect the statistics and aggregate them in a bucket. The talk will cover the usage of pg_stat_monitor and how it is better than pg_stat_statements.

Talk by Brendan Gregg for USENIX LISA 2019: Linux Systems Performance. Abstract: " Systems performance is an effective discipline for performance analysis and tuning, and can help you find performance wins for your applications and the kernel. However, most of us are not performance or kernel engineers, and have limited time to study this topic. This talk summarizes the topic for everyone, touring six important areas of Linux systems performance: observability tools, methodologies, benchmarking, profiling, tracing, and tuning. Included are recipes for Linux performance analysis and tuning (using vmstat, mpstat, iostat, etc), overviews of complex areas including profiling (perf_events) and tracing (Ftrace, bcc/BPF, and bpftrace/BPF), and much advice about what is and isn't important to learn. This talk is aimed at everyone: developers, operations, sysadmins, etc, and in any environment running Linux, bare metal or the cloud."

New Stateless support in TRex provides: - High performance packet generation of up to 22 million packets per second per core and support for interfaces from 1Gbps to 100Gbps. - Flexible traffic profiles that can generate multiple streams of traffic with programmable fields using a field engine. - Statistics on a per port, per stream, and per traffic profile basis including latency and jitter. - Python API and interactive console for automation and control.

There are many ways to run high availability with PostgreSQL. Here, we present a template for you to create your own customized, high-availability solution using Python and for maximum accessibility, a distributed configuration store like ZooKeeper or etcd.

The document discusses QEMU and adding a new device to it. It begins with an introduction to QEMU and its uses. It then discusses setting up a development environment, compiling QEMU, and examples of existing devices. The main part explains how to add a new "Devix" device by creating source files, registering the device type, initializing PCI configuration, and registering memory regions. It demonstrates basic functionality like interrupts and I/O access callbacks. The goal is to introduce developing new emulated devices for QEMU.

Netronome's half-day tutorial on host data plane acceleration at ACM SIGCOMM 2018 introduced attendees to models for host data plane acceleration and provided an in-depth understanding of SmartNIC deployment models at hyperscale cloud vendors and telecom service providers. Presenter Bios Jakub Kicinski is a long term Linux kernel contributor, who has been leading the kernel team at Netronome for the last two years. Jakub’s major contributions include the creation of BPF hardware offload mechanisms in the kernel and bpftool user space utility, as well as work on the Linux kernel side of OVS offload. David Beckett is a Software Engineer at Netronome with a strong technical background of computer networks including academic research with DDoS. David has expertise in the areas of Linux architecture and computer programming. David has a Masters Degree in Electrical, Electronic Engineering at Queen’s University Belfast and continues as a PhD student studying Emerging Application Layer DDoS threats.

The document discusses exploiting TrueType font (TTF) vulnerabilities to achieve kernel code execution on Windows systems. It begins by describing the discovery of exploitable bugs in a TTF fuzzer. Despite mitigations like KASLR, NX, SMAP, and CFG, the researchers were able to bypass these protections through techniques like controlled overflows, abusing plain kernel structures, and function-driven attacks. They show how to leverage wild overflows, control kernel memory layout, and hijack control flow to achieve arbitrary code execution. The document emphasizes that OS design weaknesses allow bypassing modern defenses through clever bug chaining and memory manipulation.

The document outlines the governance principles and processes of the Xen Project open source hypervisor community. It discusses principles of openness, transparency and meritocracy. It describes roles like maintainers, committers and project leads. It covers topics like decision making, design reviews, release processes, earning status, and resolving conflicts.

USENIX LISA2021 talk by Brendan Gregg (https://www.youtube.com/watch?v=_5Z2AU7QTH4). This talk is a deep dive that describes how BPF (eBPF) works internally on Linux, and dissects some modern performance observability tools. Details covered include the kernel BPF implementation: the verifier, JIT compilation, and the BPF execution environment; the BPF instruction set; different event sources; and how BPF is used by user space, using bpftrace programs as an example. This includes showing how bpftrace is compiled to LLVM IR and then BPF bytecode, and how per-event data and aggregated map data are fetched from the kernel.

When one server just isn’t enough, how can you scale out? In this webinar, you'll learn how to build out the capacity of your website. You'll see a variety of scalability approaches and some of the advanced capabilities of NGINX Plus. View full webinar on demand at http://nginx.com/resources/webinars/nginx-load-balancing-software/

On-demand recording: nginx.com/resources/webinars/nginx-basics-best-practices You’ve heard of NGINX and the benefits it can provide to your web application, but maybe you’re not sure how to get started. There are a lot of tutorials online, but they can be outdated and contradict each other, making things more challenging. In this webinar we’ll cover the basics of NGINX to help you effectively begin using it as part of your existing or new web app. This webinar covers how to: * Install NGINX and verify it's properly running * Create NGINX configurations for reverse proxy, load balancer, etc. * Improve performance using keepalives and other NGINX directives * Debug and troubleshoot using NGINX logs

The document discusses using RDMA (Remote Direct Memory Access) for high performance networking in Python. It describes how traditional sockets involve multiple memory copies that reduce performance. RDMA allows data to be directly placed in the receiving application's memory without intermediate copies. The document outlines an implementation of RDMA sockets in Python, called RdmaSocket, that exposes an interface similar to regular sockets but uses RDMA under the hood. Examples are given showing how it can simplify high performance networking applications in Python.

Xen Project is a static partitioning hypervisor for embedded deployments (industrial, medical, etc.) Xen enforces strong isolation between domains so that one cannot affect the execution of another. Features such as cache coloring reduce interference and improve interrupt latency and determinism. A real-time workload can run alongside a more complex guest. But can it be used in safety-critical environments? The Xen hypervisor has a microkernel design: services and tools are non-essential and run in unprivileged VMs, while the core is less than 50K LOC. This architecture lends itself well to safety-critical applications as only the core is critical and needs to go through the certification process. This presentation will describe the activities of the Xen FuSa SIG (Special Interest Group) to make Xen easier to safety-certify. It will go through the aspects of Xen that pertain safety and it will explain how to set up a mixed-criticality system with Xen. The talk will discuss the challenges of making an Open Source project safety-certifiable and the progress that the Xen community made so far in the areas of documentation and requirements, MISRA-C code compliance, and interference reduction.

This document discusses how PostgreSQL works with disks and provides recommendations for disk subsystem monitoring, hardware selection, and configuration tuning to optimize performance. It explains that PostgreSQL relies on disk I/O for reading pages, writing the write-ahead log (WAL), and checkpointing. It recommends monitoring disk utilization, IOPS, latency, and I/O wait. The document also provides tips for choosing hardware like SSDs or RAID configurations and configuring the operating system, file systems, and PostgreSQL to improve performance.

Présentation de l'outil Patroni : gestion de la haute disponibilité de PostgreSQL Meetup PostgreSQL Nantes / mars 2019

This document provides an introduction to HTML5 and CSS. It begins by asking why someone needs to learn HTML5 and CSS, then defines HTML as the language used to write websites and help computers communicate. It explains that HTML defines the content of a web page while CSS defines the style. It provides the basic structure of an HTML page, including the <head>, <body>, and <html> tags. It also gives examples of common tags like <p>, <img>, and <a> and notes that some tags close themselves while others require an ending tag. The document concludes by providing some online resources for learning more about HTML.

Dubai is set to become home to the first temperature-controlled city on the planet. The ambitious project is expected to feature a mall, an indoor family theme park, and a "network of temperature-controlled openable promenades" — all billed as "the world's largest.

The document provides information about an upcoming conference on project finance for energy and infrastructure projects in East Africa. The two-day conference will be held on July 22-23, 2015 in Dar es Salaam, Tanzania and will bring together policymakers, private sector representatives, and investors. It will include sessions on financing projects and risk assessment, driving energy development, and power and transportation infrastructure such as roads, rail, and pipelines. High-level speakers will discuss opportunities and challenges for project financing in the region.

This document describes a three-tier architecture for a user registration and login system using Java servlets. It includes code for servlets to insert and retrieve user data from a MySQL database, as well as HTML pages for the user interface. The servlets handle communication between the database and user interface tiers. The document provides instructions for setting up the database connection, compiling the Java code, configuring the web application deployment descriptor, and testing the application.

The document describes a 12-stage 3D circular puzzle process. Each stage includes text blocks arranged in a circular formation. The stages showcase how to create an engaging circular slide to explain complex processes in a clear, visual manner.

Sharlena Wood is an artist known for her expertise in charcoal and mixed media drawing. She has a passion for sharing her artistic knowledge and enthusiasm. As a self-taught artist, Sharlena encourages others to trust their creative intuition. Her cheerful attitude inspires exploration and building confidence in one's creative talents.

This document provides an overview of the upcoming week's lessons for a kindergarten classroom at Crossroads Charter Academy in Big Rapids, MI. The lessons will focus on sight words, phonics including the letter Aa sound, reading comprehension skills, sketching and story writing in writing, pattern recognition in math, and learning about past and present in science/social studies. The student teacher will now be teaching full days until November 27th. There is also information about volunteering opportunities and an upcoming Harvest Party and other events. Homework involves practicing rhyming words and identifying first sounds in words using a ten frame activity sheet.

Adobe reports record Q1 FY2016 revenue. This earnings infographic features key performance from Adobe’s Q1 FY2016 results.

This document provides information about AIM Global Inc., a company that produces food supplements and herbal products. It details the company's board of directors, manufacturing partners, product lines that include nutraceuticals and coffee/chocolate infused with supplements, clinical research supporting products, compensation plan for distributors, and goals for distributors. The document promotes AIM Global's products and business opportunities.