This document provides an overview of using Ruby to interface with Unix systems calls and interprocess communication mechanisms. It discusses Ruby libraries and methods for launching subprocesses, manipulating file descriptors, communicating between processes via pipes, sockets and shared memory, and making direct system calls via the syscall method or the DL library. The goal is to make Unix a native environment for Ruby applications.
Magic Clusters and Where to Find Them - Eugene PirogovElixir Club
The talk focuses on Erlang & Elixir facilities for distributed computing.
We'll explore how to build clusters and look at how testing a clustered setup might looks like. We'll create a Mnesia cluster and will talk about CAP theorem. We'll answer the questions of what distributed computing is for, and what Erlang has to offer with regards to balancing the load between the nodes in a cluster.
Experience this and much more in the "Magic Clusters and Where to Find Them" talk!
Elixir Meetup 4 Lviv
Magic Clusters and Where to Find Them - Eugene PirogovElixir Club
The talk focuses on Erlang & Elixir facilities for distributed computing.
We'll explore how to build clusters and look at how testing a clustered setup might looks like. We'll create a Mnesia cluster and will talk about CAP theorem. We'll answer the questions of what distributed computing is for, and what Erlang has to offer with regards to balancing the load between the nodes in a cluster.
Experience this and much more in the "Magic Clusters and Where to Find Them" talk!
Elixir Meetup 4 Lviv
[Defcon24] Introduction to the Witchcraft Compiler CollectionMoabi.com
With this presentation, we take a new approach to reverse engineering. Instead of attempting to decompile code, we seek to undo the work of the linker and produce relocatable files, the typical output of a compiler. The main benefit of the later technique over the former being that it does work. Once achieved universal code ‘reuse’ by relinking those relocatable objects as arbitrary shared libraries, we'll create a form of binary reflection, add scripting capabilities and in memory debugging using a JIT compiler, to attain automated API prototyping and annotation, which, we will argue, constitutes a primary form of binary code self awareness. Finally, we'll see how abusing the dynamic linker internals shall elegantly solve a number of complex tasks for us, such as calling a given function within a binary without having to craft a valid input to reach it.
The applications in terms of vulnerability exploitation, functional testing, static analysis validation and more generally computer wizardry being tremendous, we'll have fun demoing some new exploits in real life applications, and commit public program profanity, such as turning PEs into ELFs, functional scripting of sshd in memory, stealing crypto routines without even disassembling them, among other things that were never supposed to work. All the above techniques have been implemented into the Wichcraft Compiler Collection, to be released as proper open source software (MIT/BSD-2 licenses) exclusively at DEF CON 24.
Jonathan Brossard is a computer whisperer from France, although he's been living in Brazil, India, Australia and now lives in San Francisco. For his first conference at DEF CON 16, he hacked Microsoft Bitlocker, McAffee Endpoint and a fair number of BIOS Firmwares. During his second presentation at DEF CON 20, he presented Rakshasa, a BIOS malware based on open source software, the MIT Technology review labeled "incurable and undetectable".
This year will be his third DEF CON ... Endrazine is also known in the community for having run the Hackito Ergo Sum and NoSuchCon conferences in France, participating to the Shakacon Program Committee in Hawaii, and authoring a number of exploits over the past decade. Including the first remote Windows 10 exploit and several hardcore reverse engineering tools and whitepapers. Jonathan is part of the team behind MOABI.COM, and acts as the Principal Engineer of Product Security at Salesforce.
Twitter: @endrazine
Facebook: toucansystem
https://moabi.com
Kernel Recipes 2019 - Faster IO through io_uringAnne Nicolas
Since the dawn of time, Linux has had to make do with inferior IO interfaces. Native Linux AIO supports only a niche application class (O_DIRECT), and even for that use case, it’s far too slow for modern storage. This talk will detail io_uring, a modern IO interface for Linux, that’s both fully featured and performant.
Jens Axboe
Agenda:
In this session, Shmulik Ladkani discusses the kernel's net_device abstraction, its interfaces, and how net-devices interact with the network stack. The talk covers many of the software network devices that exist in the Linux kernel, the functionalities they provide and some interesting use cases.
Speaker:
Shmulik Ladkani is a Tech Lead at Ravello Systems.
Shmulik started his career at Jungo (acquired by NDS/Cisco) implementing residential gateway software, focusing on embedded Linux, Linux kernel, networking and hardware/software integration.
51966 coffees and billions of forwarded packets later, with millions of homes running his software, Shmulik left his position as Jungo’s lead architect and joined Ravello Systems (acquired by Oracle) as tech lead, developing a virtual data center as a cloud service. He's now focused around virtualization systems, network virtualization and SDN.
I am Anne L. I am an Operating System Assignment Expert at programminghomeworkhelp.com. I hold a Ph.D. in Programming, Auburn University, USA. I have been helping students with their homework for the past 8 years. I solve assignments related to Operating systems.
Visit programminghomeworkhelp.com or email support@programminghomeworkhelp.com.
You can also call on +1 678 648 4277 for any assistance with Operating System Assignments.
I am Irene. I am a Computer Science Assignment Help Expert at programminghomeworkhelp.com. I hold a Ph.D. in Computer Science from, California Institute of Technology. I have been helping students with their homework for the past 8 years. I solve assignments related to Computer Science.
Visit programminghomeworkhelp.com or email support@programminghomeworkhelp.com.
You can also call on +1 678 648 4277 for any assistance with Computer Science assignments.
The heavyweight "process model", historically used by Unix systems, including Linux, to split a large system into smaller, more tractable pieces doesn’t always lend itself to embedded environments
owing to substantial computational overhead. POSIX threads, also known as Pthreads, is a multithreading API that looks more like what embedded programmers are used to but runs in a
Unix/Linux environment. This presentation introduces Posix Threads and shows you how to use threads to create more efficient, more responsive programs.
Finding a useful outlet for my many Adventures in goEleanor McHugh
A talk about my Leanpub-published living eBook: A Go Developer's Notebook. Buy my book? Write your own Book using Leanpub? Learn you some Golang for fun?
[Defcon24] Introduction to the Witchcraft Compiler CollectionMoabi.com
With this presentation, we take a new approach to reverse engineering. Instead of attempting to decompile code, we seek to undo the work of the linker and produce relocatable files, the typical output of a compiler. The main benefit of the later technique over the former being that it does work. Once achieved universal code ‘reuse’ by relinking those relocatable objects as arbitrary shared libraries, we'll create a form of binary reflection, add scripting capabilities and in memory debugging using a JIT compiler, to attain automated API prototyping and annotation, which, we will argue, constitutes a primary form of binary code self awareness. Finally, we'll see how abusing the dynamic linker internals shall elegantly solve a number of complex tasks for us, such as calling a given function within a binary without having to craft a valid input to reach it.
The applications in terms of vulnerability exploitation, functional testing, static analysis validation and more generally computer wizardry being tremendous, we'll have fun demoing some new exploits in real life applications, and commit public program profanity, such as turning PEs into ELFs, functional scripting of sshd in memory, stealing crypto routines without even disassembling them, among other things that were never supposed to work. All the above techniques have been implemented into the Wichcraft Compiler Collection, to be released as proper open source software (MIT/BSD-2 licenses) exclusively at DEF CON 24.
Jonathan Brossard is a computer whisperer from France, although he's been living in Brazil, India, Australia and now lives in San Francisco. For his first conference at DEF CON 16, he hacked Microsoft Bitlocker, McAffee Endpoint and a fair number of BIOS Firmwares. During his second presentation at DEF CON 20, he presented Rakshasa, a BIOS malware based on open source software, the MIT Technology review labeled "incurable and undetectable".
This year will be his third DEF CON ... Endrazine is also known in the community for having run the Hackito Ergo Sum and NoSuchCon conferences in France, participating to the Shakacon Program Committee in Hawaii, and authoring a number of exploits over the past decade. Including the first remote Windows 10 exploit and several hardcore reverse engineering tools and whitepapers. Jonathan is part of the team behind MOABI.COM, and acts as the Principal Engineer of Product Security at Salesforce.
Twitter: @endrazine
Facebook: toucansystem
https://moabi.com
Kernel Recipes 2019 - Faster IO through io_uringAnne Nicolas
Since the dawn of time, Linux has had to make do with inferior IO interfaces. Native Linux AIO supports only a niche application class (O_DIRECT), and even for that use case, it’s far too slow for modern storage. This talk will detail io_uring, a modern IO interface for Linux, that’s both fully featured and performant.
Jens Axboe
Agenda:
In this session, Shmulik Ladkani discusses the kernel's net_device abstraction, its interfaces, and how net-devices interact with the network stack. The talk covers many of the software network devices that exist in the Linux kernel, the functionalities they provide and some interesting use cases.
Speaker:
Shmulik Ladkani is a Tech Lead at Ravello Systems.
Shmulik started his career at Jungo (acquired by NDS/Cisco) implementing residential gateway software, focusing on embedded Linux, Linux kernel, networking and hardware/software integration.
51966 coffees and billions of forwarded packets later, with millions of homes running his software, Shmulik left his position as Jungo’s lead architect and joined Ravello Systems (acquired by Oracle) as tech lead, developing a virtual data center as a cloud service. He's now focused around virtualization systems, network virtualization and SDN.
I am Anne L. I am an Operating System Assignment Expert at programminghomeworkhelp.com. I hold a Ph.D. in Programming, Auburn University, USA. I have been helping students with their homework for the past 8 years. I solve assignments related to Operating systems.
Visit programminghomeworkhelp.com or email support@programminghomeworkhelp.com.
You can also call on +1 678 648 4277 for any assistance with Operating System Assignments.
I am Irene. I am a Computer Science Assignment Help Expert at programminghomeworkhelp.com. I hold a Ph.D. in Computer Science from, California Institute of Technology. I have been helping students with their homework for the past 8 years. I solve assignments related to Computer Science.
Visit programminghomeworkhelp.com or email support@programminghomeworkhelp.com.
You can also call on +1 678 648 4277 for any assistance with Computer Science assignments.
The heavyweight "process model", historically used by Unix systems, including Linux, to split a large system into smaller, more tractable pieces doesn’t always lend itself to embedded environments
owing to substantial computational overhead. POSIX threads, also known as Pthreads, is a multithreading API that looks more like what embedded programmers are used to but runs in a
Unix/Linux environment. This presentation introduces Posix Threads and shows you how to use threads to create more efficient, more responsive programs.
Finding a useful outlet for my many Adventures in goEleanor McHugh
A talk about my Leanpub-published living eBook: A Go Developer's Notebook. Buy my book? Write your own Book using Leanpub? Learn you some Golang for fun?
This Slide talks about multithreading in python with sample code snippets.
Connect me at
https://nextsrini.blogspot.com/
https://www.youtube.com/channel/UCqIHkbuf1uGiN8QXwWX5dkQ
This is a short introduction to some basic concepts about device drivers on Linux, and does not get into the nuts and bolts of it; uses a serial driver as an example, and how does it fit within the TTY layer. Includes code walk-through.
Concurrent Programming with Ruby and Tuple Spacesluccastera
Ruby threads are limited due to the Global Interpreter Lock. Therefore, the best way to do parallel computing with Ruby is to use multiple processes but how do you get these processes to communicate?
This session will provide some strategies for handling multi-process communication in Ruby, with a focus on the use of TupleSpaces. A TupleSpace provides a repository of tuples that can be accessed concurrently to implement a Blackboard system. Ruby ships with a built-in implementation of a TupleSpace with the Rinda library.
During the session, Luc will demonstrate how to use Rinda and will highlight other libraries/projects that facilitate interprocess communication and parallel computing in Ruby.
At a time when Herbt Sutter announced to everyone that the free lunch is over (The Free Lunch Is Over: A Fundamental Turn Toward Concurrency in Software), concurrency has become our everyday life.A big change is coming to Java, the Loom project and with it such new terms as "virtual thread", "continuations" and "structured concurrency". If you've been wondering what they will change in our daily work or
whether it's worth rewriting your Tomcat-based application to super-efficient reactive Netty,or whether to wait for Project Loom? This presentation is for you.
I will talk about the Loom project and the new possibilities related to virtual wattles and "structured concurrency". I will tell you how it works and what can be achieved and the impact on performance
The first cut of a talk on the R&D process in software development, including taking an invention to patent.
Includes two sets of code examples. One is Forth implemented in a 1980s dialect of Basic.
The other introduces evolutionary prototyping using a hybrid ruby/bash methodology.
Generics, Reflection, and Efficient CollectionsEleanor McHugh
This is a talk about how we structure and collate information so as to effectively process it, the language tools Go provides to help us do this, and the sometimes frustrating tradeoffs we must make when marry the real world with the digital.
We'll start by looking at basic collection types in Go: array, slice, map, and channel. These will then be used as the basis for our own user defined types with methods for processing the collected items.
These methods will then be expanded to take functions as parameters (the higher order functional style popularised by languages such as Ruby) and by using Go's Reflection package we will generalise them for a variety of tasks and uses cases.
Reflection adds an interpreted element to our programs with a resulting performance cost. Careful design can often minimise this cost and it may well amortise to zero on a sufficiently large collection however there is always greater code complexity to manage. When the data to be contained in a user defined collection is homogenous we can reduce much of this complexity by using Generics and our next set of examples will demonstrate this.
At the end of this talk you should have some useful ideas for designing your own collection types in Go as well as a reasonable base from which to explore Reflection, Generics, and the Higher-Order Functional style of programming.
Go for the paranoid network programmer, 3rd editionEleanor McHugh
Draft third edition of my #golang network programming and cryptography talk given to the Belfast Gophers Meetup. Now with an introduction to websockets.
An introduction to functional programming with goEleanor McHugh
A crash course in functional programming concepts using Go. Heavy on code, light on theory.
You can find the examples at https://github.com/feyeleanor/intro_to_fp_in_go
Implementing virtual machines in go & c 2018 reduxEleanor McHugh
An updated version of my talk on virtual machine cores comparing techniques in C and Go for implementing dispatch loops, stacks & hash maps.
Lots of tested and debugged code is provided as well as references to some useful/interesting books.
Digital Identity talk from Strange Loop 2018 and Build Stuff Lithuania 2018 including walkthrough of the uPass system and the design principles behind it.
Don't Ask, Don't Tell - The Virtues of Privacy By DesignEleanor McHugh
This is a fairly technical overview of the considerations involved in architecting software systems to support privacy. Rather than focus on what the law demands - something which can change across time and jurisdictions - it looks at the real problems we need to solve to know as little about the users of computer systems as possible whilst achieving their needs.
Don't ask, don't tell the virtues of privacy by designEleanor McHugh
A very light intro talk on privacy, identity, and designing with the latter to preserve the former.
Probably makes no sense at all without the audio so if it whet's your appetite dig through my other decks on these topics. Most of those have code in for the more technically minded.
An overview of the uPass digital identity system. Covers the core problem domain and the end-to-end stack from liveness to black-box transaction store. Lots of diagrams, references to all the relevant patent applications and so forth.
An introduction to Go from basics to web through the lens of "Hello World", extracted from the Book "A Go Developer's Notebook" available from http://leanpub.com/GoNotebook
Implementing Software Machines in C and GoEleanor McHugh
The next iteration of the talk I gave at Progscon, this introduces examples of Map implementation (useful for caches etc.) and outlines for addition of processor core code in a later talk.
Implementing Software Machines in Go and CEleanor McHugh
Early draft of a tutorial on techniques for implementing virtual machines and language interpreters. Contains example programs for functional stacks and despatch loops.
LF Energy Webinar: Electrical Grid Modelling and Simulation Through PowSyBl -...DanBrown980551
Do you want to learn how to model and simulate an electrical network from scratch in under an hour?
Then welcome to this PowSyBl workshop, hosted by Rte, the French Transmission System Operator (TSO)!
During the webinar, you will discover the PowSyBl ecosystem as well as handle and study an electrical network through an interactive Python notebook.
PowSyBl is an open source project hosted by LF Energy, which offers a comprehensive set of features for electrical grid modelling and simulation. Among other advanced features, PowSyBl provides:
- A fully editable and extendable library for grid component modelling;
- Visualization tools to display your network;
- Grid simulation tools, such as power flows, security analyses (with or without remedial actions) and sensitivity analyses;
The framework is mostly written in Java, with a Python binding so that Python developers can access PowSyBl functionalities as well.
What you will learn during the webinar:
- For beginners: discover PowSyBl's functionalities through a quick general presentation and the notebook, without needing any expert coding skills;
- For advanced developers: master the skills to efficiently apply PowSyBl functionalities to your real-world scenarios.
Key Trends Shaping the Future of Infrastructure.pdfCheryl Hung
Keynote at DIGIT West Expo, Glasgow on 29 May 2024.
Cheryl Hung, ochery.com
Sr Director, Infrastructure Ecosystem, Arm.
The key trends across hardware, cloud and open-source; exploring how these areas are likely to mature and develop over the short and long-term, and then considering how organisations can position themselves to adapt and thrive.
State of ICS and IoT Cyber Threat Landscape Report 2024 previewPrayukth K V
The IoT and OT threat landscape report has been prepared by the Threat Research Team at Sectrio using data from Sectrio, cyber threat intelligence farming facilities spread across over 85 cities around the world. In addition, Sectrio also runs AI-based advanced threat and payload engagement facilities that serve as sinks to attract and engage sophisticated threat actors, and newer malware including new variants and latent threats that are at an earlier stage of development.
The latest edition of the OT/ICS and IoT security Threat Landscape Report 2024 also covers:
State of global ICS asset and network exposure
Sectoral targets and attacks as well as the cost of ransom
Global APT activity, AI usage, actor and tactic profiles, and implications
Rise in volumes of AI-powered cyberattacks
Major cyber events in 2024
Malware and malicious payload trends
Cyberattack types and targets
Vulnerability exploit attempts on CVEs
Attacks on counties – USA
Expansion of bot farms – how, where, and why
In-depth analysis of the cyber threat landscape across North America, South America, Europe, APAC, and the Middle East
Why are attacks on smart factories rising?
Cyber risk predictions
Axis of attacks – Europe
Systemic attacks in the Middle East
Download the full report from here:
https://sectrio.com/resources/ot-threat-landscape-reports/sectrio-releases-ot-ics-and-iot-security-threat-landscape-report-2024/
Essentials of Automations: Optimizing FME Workflows with ParametersSafe Software
Are you looking to streamline your workflows and boost your projects’ efficiency? Do you find yourself searching for ways to add flexibility and control over your FME workflows? If so, you’re in the right place.
Join us for an insightful dive into the world of FME parameters, a critical element in optimizing workflow efficiency. This webinar marks the beginning of our three-part “Essentials of Automation” series. This first webinar is designed to equip you with the knowledge and skills to utilize parameters effectively: enhancing the flexibility, maintainability, and user control of your FME projects.
Here’s what you’ll gain:
- Essentials of FME Parameters: Understand the pivotal role of parameters, including Reader/Writer, Transformer, User, and FME Flow categories. Discover how they are the key to unlocking automation and optimization within your workflows.
- Practical Applications in FME Form: Delve into key user parameter types including choice, connections, and file URLs. Allow users to control how a workflow runs, making your workflows more reusable. Learn to import values and deliver the best user experience for your workflows while enhancing accuracy.
- Optimization Strategies in FME Flow: Explore the creation and strategic deployment of parameters in FME Flow, including the use of deployment and geometry parameters, to maximize workflow efficiency.
- Pro Tips for Success: Gain insights on parameterizing connections and leveraging new features like Conditional Visibility for clarity and simplicity.
We’ll wrap up with a glimpse into future webinars, followed by a Q&A session to address your specific questions surrounding this topic.
Don’t miss this opportunity to elevate your FME expertise and drive your projects to new heights of efficiency.
GDG Cloud Southlake #33: Boule & Rebala: Effective AppSec in SDLC using Deplo...James Anderson
Effective Application Security in Software Delivery lifecycle using Deployment Firewall and DBOM
The modern software delivery process (or the CI/CD process) includes many tools, distributed teams, open-source code, and cloud platforms. Constant focus on speed to release software to market, along with the traditional slow and manual security checks has caused gaps in continuous security as an important piece in the software supply chain. Today organizations feel more susceptible to external and internal cyber threats due to the vast attack surface in their applications supply chain and the lack of end-to-end governance and risk management.
The software team must secure its software delivery process to avoid vulnerability and security breaches. This needs to be achieved with existing tool chains and without extensive rework of the delivery processes. This talk will present strategies and techniques for providing visibility into the true risk of the existing vulnerabilities, preventing the introduction of security issues in the software, resolving vulnerabilities in production environments quickly, and capturing the deployment bill of materials (DBOM).
Speakers:
Bob Boule
Robert Boule is a technology enthusiast with PASSION for technology and making things work along with a knack for helping others understand how things work. He comes with around 20 years of solution engineering experience in application security, software continuous delivery, and SaaS platforms. He is known for his dynamic presentations in CI/CD and application security integrated in software delivery lifecycle.
Gopinath Rebala
Gopinath Rebala is the CTO of OpsMx, where he has overall responsibility for the machine learning and data processing architectures for Secure Software Delivery. Gopi also has a strong connection with our customers, leading design and architecture for strategic implementations. Gopi is a frequent speaker and well-known leader in continuous delivery and integrating security into software delivery.
GraphRAG is All You need? LLM & Knowledge GraphGuy Korland
Guy Korland, CEO and Co-founder of FalkorDB, will review two articles on the integration of language models with knowledge graphs.
1. Unifying Large Language Models and Knowledge Graphs: A Roadmap.
https://arxiv.org/abs/2306.08302
2. Microsoft Research's GraphRAG paper and a review paper on various uses of knowledge graphs:
https://www.microsoft.com/en-us/research/blog/graphrag-unlocking-llm-discovery-on-narrative-private-data/
Epistemic Interaction - tuning interfaces to provide information for AI supportAlan Dix
Paper presented at SYNERGY workshop at AVI 2024, Genoa, Italy. 3rd June 2024
https://alandix.com/academic/papers/synergy2024-epistemic/
As machine learning integrates deeper into human-computer interactions, the concept of epistemic interaction emerges, aiming to refine these interactions to enhance system adaptability. This approach encourages minor, intentional adjustments in user behaviour to enrich the data available for system learning. This paper introduces epistemic interaction within the context of human-system communication, illustrating how deliberate interaction design can improve system understanding and adaptation. Through concrete examples, we demonstrate the potential of epistemic interaction to significantly advance human-computer interaction by leveraging intuitive human communication strategies to inform system design and functionality, offering a novel pathway for enriching user-system engagements.
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
In this presentation, we examine the challenges and limitations of relying too heavily on PHP frameworks in web development. We discuss the history of PHP and its frameworks to understand how this dependence has evolved. The focus will be on providing concrete tips and strategies to reduce reliance on these frameworks, based on real-world examples and practical considerations. The goal is to equip developers with the skills and knowledge to create more flexible and future-proof web applications. We'll explore the importance of maintaining autonomy in a rapidly changing tech landscape and how to make informed decisions in PHP development.
This talk is aimed at encouraging a more independent approach to using PHP frameworks, moving towards a more flexible and future-proof approach to PHP development.
Let's dive deeper into the world of ODC! Ricardo Alves (OutSystems) will join us to tell all about the new Data Fabric. After that, Sezen de Bruijn (OutSystems) will get into the details on how to best design a sturdy architecture within ODC.
Neuro-symbolic is not enough, we need neuro-*semantic*Frank van Harmelen
Neuro-symbolic (NeSy) AI is on the rise. However, simply machine learning on just any symbolic structure is not sufficient to really harvest the gains of NeSy. These will only be gained when the symbolic structures have an actual semantics. I give an operational definition of semantics as “predictable inference”.
All of this illustrated with link prediction over knowledge graphs, but the argument is general.
UiPath Test Automation using UiPath Test Suite series, part 3DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 3. In this session, we will cover desktop automation along with UI automation.
Topics covered:
UI automation Introduction,
UI automation Sample
Desktop automation flow
Pradeep Chinnala, Senior Consultant Automation Developer @WonderBotz and UiPath MVP
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
UiPath Test Automation using UiPath Test Suite series, part 4DianaGray10
Welcome to UiPath Test Automation using UiPath Test Suite series part 4. In this session, we will cover Test Manager overview along with SAP heatmap.
The UiPath Test Manager overview with SAP heatmap webinar offers a concise yet comprehensive exploration of the role of a Test Manager within SAP environments, coupled with the utilization of heatmaps for effective testing strategies.
Participants will gain insights into the responsibilities, challenges, and best practices associated with test management in SAP projects. Additionally, the webinar delves into the significance of heatmaps as a visual aid for identifying testing priorities, areas of risk, and resource allocation within SAP landscapes. Through this session, attendees can expect to enhance their understanding of test management principles while learning practical approaches to optimize testing processes in SAP environments using heatmap visualization techniques
What will you get from this session?
1. Insights into SAP testing best practices
2. Heatmap utilization for testing
3. Optimization of testing processes
4. Demo
Topics covered:
Execution from the test manager
Orchestrator execution result
Defect reporting
SAP heatmap example with demo
Speaker:
Deepak Rai, Automation Practice Lead, Boundaryless Group and UiPath MVP
Smart TV Buyer Insights Survey 2024 by 91mobiles.pdf91mobiles
91mobiles recently conducted a Smart TV Buyer Insights Survey in which we asked over 3,000 respondents about the TV they own, aspects they look at on a new TV, and their TV buying preferences.
JMeter webinar - integration with InfluxDB and GrafanaRTTS
Watch this recorded webinar about real-time monitoring of application performance. See how to integrate Apache JMeter, the open-source leader in performance testing, with InfluxDB, the open-source time-series database, and Grafana, the open-source analytics and visualization application.
In this webinar, we will review the benefits of leveraging InfluxDB and Grafana when executing load tests and demonstrate how these tools are used to visualize performance metrics.
Length: 30 minutes
Session Overview
-------------------------------------------
During this webinar, we will cover the following topics while demonstrating the integrations of JMeter, InfluxDB and Grafana:
- What out-of-the-box solutions are available for real-time monitoring JMeter tests?
- What are the benefits of integrating InfluxDB and Grafana into the load testing stack?
- Which features are provided by Grafana?
- Demonstration of InfluxDB and Grafana using a practice web application
To view the webinar recording, go to:
https://www.rttsweb.com/jmeter-integration-webinar
5. on the road to perdition
“Are you God’s work, or the Devil’s? Oh, what do
I care whose work you are? You poor silent
creature.”
- A Company of Wolves
6. caveat lector
danger! we’re entering strange territory
our map will be missing some major landmarks
and will be riddled with inaccuracies
so don’t try this on a live production system
and read your man pages thoroughly
8. it’s smart to be lazy
create small tools
to solve simple tasks effectively
perform each task independently
and pass the results from one task to another
using a clean interface
thus solving complex problems sociably
10. totally punk
“if you give people the license to be as
outrageous as they want in absolutely any
fashion they can dream up, they’ll be creative
about it, and do something good besides”
- Lester Bangs
12. basic services
virtual memory
process management
hierarchical file system
user permissions
interprocess communication
signals and interrupts
execution environment
13. anatomy of a process
program instructions
program data
system data (file descriptors, user, group, parent, etc.)
environment data
supports one or more threads of execution
preemptively scheduled by the kernel
14. process creation
a process may spawn child processes via fork()
this creates a duplicate child process
with duplicate file descriptors and program state
which can be replaced via exec() of a new program
all processes ultimately derive from the init process
which is created by the kernel at boot
15. a costly strategy
sometimes we only want a blank slate process
but fork() copies the full process state
so BSD introduced vfork() which shares data memory
whilst POSIX introduced spawn()
most fork() implementations now use copy-on-write
so the advantages of vfork() have diminished
16. with certain limitations
only the thread which forks will be in the child process
a green threads system can work around this
although Ruby 1.8 doesn’t seem to
it’s also possible for exec() to fail
so forked processes need to guard for this
17. and a taste for brains
a zombie is a subprocess which outlives its parent
zombies are members of the system process group
and are eventually terminated
but until then they retain resources
and may not flush all of their IO buffers
18. Kernel.system [env ,] cmnd [, args] [, options] => true or false or nil
Kernel.spawn [env ,] cmnd [, args] [, options] => pid
The simplest way to take advantage of multiple processes in Ruby is to
launch a subshell and either block until it terminates or keep a note of its
process ID so this can be checked later. This is an opaque method and
not useful when the parent process wishes to capture results.
IO.` cmd ` => string
The next step up in utility from system() and spawn(), the backquote
method captures standard output from the subshell and as a bonus
stores a Process::Status object in the thread-global $? variable.
19. IO.popen cmd [, mode = quot;rquot;] => io
IO.popen cmd [, mode = quot;rquot; [{ | io | block }] => obj
Invokes a command shell in a subprocess and executes the specified
commands, providing a [uni|bi]directional pipe which the parent process
can use to communicate with the subprocess.
Open3.popen3 cmd [{ |stdin, stdout, stderr| block }]
Open3.popen3 cmd => array
A wrapper for spawn() which provides access to the standard IO streams
of the subshell along with a thread waiting on it.
20. Kernel.fork [{ block }] => fixnum or nil
Process.fork [{ block }] => fixnum or nil
Ruby provides its own fork() implementation which can either take a
block and run it in a subprocess, or can allow a more traditional split in
execution paths. No IPC mechanism is provided beyond allowing the
parent to wait on the child process and receive an error code.
Kernel.exec [env ,] cmnd [, args] [, options]
And as you’d expect it also allows access to the exec() family of system
calls. This is a rare core library methods which doesn’t return a value for
the simple reason that the existing program ceases to exist unless an
error occurs, and that’s flagged with a SystemCallError exception. It’s
common practice to terminate the program or retry exec() after a delay.
21. file descriptors
the kernel keeps a table of open files for each process
an integer index is used to reference entries
and is known as a file descriptor
unix is liberal about what counts as a file
and most descriptors are inherited by child processes
22. beware the subtleties
file descriptors are unique to a process
so closing a descriptor only affects that process
but the underlying descriptions are shared
performing an lseek() changes the description
and can therefore affect other processes
with much hilarity ensuing...
23. IO.sysopen path [, mode [, perm] => fixnum
io.sysread int [, buffer] => string
io.syswrite string => int
io.sysseek offset, whence = SEEK_SET => int
These methods make direct calls to the kernel to open and manipulate
the contents of files, bypassing buffering. They shouldn’t be used with
higher-level methods such as IO#read as unpredictable results may occur.
Errors are raised as Exceptions in the Errno namespace.
24. IO.new fd [, mode] [, opt] => io
IO.for_fd fd [, mode] [, opt] => io
Returns a new IO object (a stream) for the given IO object or integer file
descriptor and mode string. See also IO#fileno and IO.for_fd.
a = IO.new(2,quot;wquot;) # '2' is standard error
$stderr.puts quot;Helloquot;
a.puts quot;Worldquot;
produces:
Hello
World
26. handling many files at once
file access is much slower than memory access
this causes threads and processes to block
so usually IO is buffered by the kernel
and non-blocking access methods are implemented
however this is still ineffient when writing servers
27. select rd_ary [, wrt_ary] [, err_ary] [, timeout] => array or nil
Select is the standard low-level method for polling many IO streams at
once and it’s a blocking call, hence the need for a timeout. For writing
socket servers etc. this usually works reasonably well and Ruby’s
implementation plays nicely with threads.
28. kernel eventing
allows the kernel to raise events for streams
a process can then poll for events without blocking
on BSD this is handled by kqueue
on Linux by epoll and inotify
epoll is much more efficient that inotify
EventMachine makes use of whichever it can find
29. Interprocess Communication
IPC objects have descriptors like files
but they don’t need to exist in the file system
POSIX and System V interfaces
System V uses keys to identify IPC objects
keys can be generated from paths using ftok()
POSIX uses paths to identify IPC objects
30. pipes
provides a pair of end-points for processes to talk
an unnamed pipe connects related processes
a named pipe is like a file
it has user permissions
and can be accessed by unrelated processes
31. IO.pipe => read_file, write_file
Ruby supports anonymous pipes, which can be used to communicate
between a parent a child process, taking advantage of the fact that the
file descriptors for the end-points will exist across a fork().
Good practice is for the parent process to close the reading end of the
pipe whilst the child closes the writing end as soon as they return from
fork() and the child should also close the reading end before it terminates
to ensure buffered data is properly flushed.
34. shared memory
a single defined region of virtual memory
can be mapped into many different processes
each of which can modify it
this offers a flexible form of IPC
but to be effective requires synchronisation
ruby has no direct support for shared memory
37. from the docs
Kernel#syscall fixnum [, args...] => integer
Calls the operating system function identified by fixnum, passing in the
arguments, which must be either String objects, or Integer objects that
ultimately fit within a native long. Up to nine parameters may be passed
(14 on the Atari-ST). The function identified by fixnum is system
dependent. On some Unix systems, the numbers may be obtained from a
header file called syscall.h.
syscall 4, 1, “hellon”, 6 # ‘4’ is write(2) on our box
produces:
hello
38. finding your syscall codes
MacOS X
/usr/include/sys/syscall.h
Linux
/usr/include/asm/unistd_32.h
/usr/include/asm/unistd_64.h
39. a fragile approach
the native syscall is a very primitive interface
error codes
file descriptors & pointer addresses
modifiable buffers
ruby syscall doesn’t support modifiable buffers
but it does wrap errors as Errno exceptions
40. IO.sysx the hard way
On MacOS X
file = syscall 5, “test.dat”, 1 # open O_WRONLY (fcntl.h)
syscall 4, file, “some textn”, 10 # write
syscall 3, file, “”, 5 # read
syscall 6, file # close
produces:
Errno::EFAULT: Bad address should be Errno::EBADF
41. posix semaphores
process 1 process 2
require ‘fcntl’ Open, Wait, TryWait, Post = 268, 271, 272, 273
Open, Wait, Post, Close = 268, 271, 273, 269 s = syscall Open, “/tmp/s”
s = syscall Open, “/tmp/s”, Fcntl::O_CREAT, 1911 begin
syscall Wait, s t = Time.now
puts “locked at #{Time.now}” syscall TryWait, s
sleep 50 puts “locked at #{t}”
puts “posted at #{Time.now}” rescue Exception => e
syscall Post, s puts “busy at #{t}”
syscall Close, s syscall Wait, s
puts “waited #{Time.now - t} seconds”
end
produces: produces:
locked at Thu May 28 01:03:23 +0100 2009 busy at Thu May 28 01:03:36 +0100 2009
posted at Thu May 28 01:04:13 +0100 2009 waited 47.056508 seconds
42. complex parameters
some kernel calls accept structured data types
ruby represents these as String objects
which can be prepared with
Array#pack
Joel VanderWerf’s bit-struct library
both approaches allow embedded nulls
but on 1.9 remember to use 8-bit ASCII encoding
43. except when they don’t
On Ruby 1.8.7 or 1.9.1 (upto patch 129)
syscall 4, 1, “hellon#{0.chr}goodbyen”, 15
produces:
ArgumentError: string contains null byte
from (irb):1:in `syscall'
from (irb):1
from /usr/local/bin/irb19:12:in `<main>'
This should be fixed in patch 130.
45. ruby/dl
part of the standard library since ruby 1.8
access to dynamically loaded libraries
.dll on windows
.so and .dylib on unix
supports C-style memory access
and callback functions written in Ruby
47. require ‘dl’ file = open “test.dat”, 0x0209
CRT = DL.dlopen ‘libc.dylib’ write file, “textn”
F = ‘syscall’ close file
def open file, mode file = open “test.dat”, 0x0000
CRT[F, ‘IISI’].call(5, file, mode)[0] text = read file, 10
end close file
def write fd, string, bytes = string.length
CRT[F, ‘IIISI’].call(4, fd, string, bytes)[0]
end
def read fd, bytes = 1
buffer = DL.malloc(bytes)
CRT[F, ‘IIIsI’].call(3, fd, buffer, bytes)[1][2]
end
def close fd
CRT[F, ‘III’].call(6, fd)[0]
end
48. memory management
memory pointers encapsulated by DL::PtrData
garbage collected
uses free() or a custom deallocator
handles realloc() automatically
plays nicely with ruby strings and arrays
[String|Array].to_ptr
PtrData.struct! and PtrData.union!