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  • Mouse clicks automatically / Raton hace clicks automaticos

    - by Antoni Ghalam
    Good day friends, my problem is that my mouse clicks automatically and is getting on my nerves. I tried to do the solutioned mentioned here: Press Alt + F2 and type gnome-mouse-properties then press Enter. Go to Accessibility tab and uncheck the option "Initiate click when stopping..." but my problem is that the Accessibility tab is not there. Buenos dias amigo tengo el problema de que mi raton da clicks automaticos y me fasidia mucho intente hacer la solucion que tu diste aqui. Haga clic en Alt + F2 y poner gnome-mouse-properties y pulsa enter. Ir a la accesibilidad y desmarque la opción "iniciar haga clic en ..." pero mi problema es q no me aparese la pestaña de accesibilidad me podrias ayudar porfavor

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  • skills that can't be outsourced- web development related

    - by Matt Derami
    I never know where it's acceptable to post something like this, so please forgive if it's in the wrong place. I'm very interested in going further in to web development; I know a bit of javascript, a bit of php, and so forth, but I'm now seeing these services that will go from psd to wordpress for 200 bucks and I'm wondering how the hell is anyone able to compete with this? So I'm wondering if those more knowledgeable than me could tell me what areas are the least likely to be able to be outsourced, for 5 bucks to some kid in Uzbekistan( no offense to that kid).. do you think it's on the database management side, or maybe app development? ideas appreciated.

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  • What's My Problem? What's Your Problem?

    - by Jacek Ziabicki
    Software installers are not made for building demo environments. I can say this much after 12 years (on and off) of supporting my fellow sales consultants with environments for software demonstrations. When we release software, we include installation programs and procedures that are designed for use by our clients – to build a production environment and a limited number of testing, training and development environments. Different Objectives Your priorities when building an environment for client use vs. building a demo environment are very different. In a production environment, security, stability, and performance concerns are paramount. These environments are built on a specific server and rarely, if ever, moved to a different server or different network address. There is typically just one application running on a particular server (physical or virtual). Once built, the environment will be used for months or years at a time. Because of security considerations, the installation program wants to make these environments very specific to the organization using the software and the use case, encoding a fully qualified name of the server, or even the IP address on the network, in the configuration. So you either go through the installation procedure for each environment, or learn how to clone and reconfigure the software as a separate instance to build all your non-production environments. This may not matter much if the installation is as simple as clicking on the Setup program. But for enterprise applications, you have a number of configuration settings that you need to get just right – so whether you are installing from scratch or reconfiguring an existing installation, this requires both time and expertise in the particular piece of software. If you need a setup of several applications that are integrated to talk to one another, it is a whole new level of complexity. Now you need the expertise in all of the applications involved (plus the supporting technology products), and in addition to making each application work, you also have to configure the integration endpoints. Each application needs the URLs and credentials to call the integration layer, and the integration must be able to call each application. Then you have to make sure that each app has the right data so a business process initiated in one application can continue in the next. And, you will need to check that each application has the correct version and patch level for the integration to work. When building demo environments, your #1 concern is agility. If you can get away with a small number of long-running environments, you are lucky. More likely, you may get a request for a dedicated environment for a demonstration that is two weeks away: how quickly can you make this available so we still have the time to build the client-specific data? We are running a hands-on workshop next month, and we’ll need 15 instances of application X environment so each student can have a separate server for the exercises. We cannot connect to our data center from the client site, the client’s security policy won’t allow our VPN to go through – so we need a portable environment that we can bring with us. Our consultants need to be able to work at the hotel, airport, and the airplane, so we really want an environment that can run on a laptop. The client will need two playpen environments running in the cloud, accessible from their network, for a series of workshops that start two weeks from now. We have seen all of these scenarios and more. Here you would be much better served by a generic installation that would be easy to clone. Welcome to the Wonder Machine The reason I started this blog is to share a particular design of a demo environment, a special way to install software, that can address the above requirements, even for integrated setups. This design was created by a team at Oracle Utilities Global Business Unit, and we are using this setup for most of our demo environments. In a bout of modesty we called it the Wonder Machine. Over the next few posts – think of it as a novel in parts – I will tell you about the big idea, how it was implemented and what you can do with it. After we have laid down the groundwork, I would like to share some tips and tricks for users of our Wonder Machine implementation, as well as things I am learning about building portable, cloneable environments. The Wonder Machine is by no means a closed specification, it is under active development! I am hoping this blog will be of interest to two groups of readers – the users of the Wonder Machine we have built at Oracle Utilities, who want to get the most out of their demo environments and be able to reconfigure it to their needs – and to people who need to build environments for demonstration, testing, training, development and would like to make them cloneable and portable to maximize the reuse of their effort. Surely we are not the only ones facing this problem? If you can think of a better way to solve it, or if you can help us improve on our concept, I will appreciate your comments!

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  • What steps to take in resolving/fixing/optimizing a long boot, with possible looping errors as the culprit

    - by Tchalvak
    So my boot time has been slowing and slowing as time has gone on... I am running a number of services (e.g. apache/mysql, postgresql), but it has seen a drastic slowing lately, while I've only been applying updates as normal. I happened to check out my /var/log/boot.log and it is spammed with many lines of this: init: upstart-udev-bridge main process (2738) terminated with status 1 init: upstart-udev-bridge main process ended, respawning I wasn't able to find any solutions to that issue in google, or much talk of it at all, and I'm not really certain that error is the problem, but it is the only lead that I have. What steps should I go through to diagnose boot problems/a slow bootup?

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  • Cisco AnyConnect VPN Client broke my internet

    - by user137864
    I was using the AnyConnect client when it froze and I had to do a hard reboot of my computer. Now I can't connect to the internet at all, with or without VPN. The Network Connections manager seems to think I have a wired and wireless connection without a problem, but I can't go online. I have tried using /etc/init.d/networking restart and it even says it is "ok" with no luck. I am guessing I need to clear some settings somewhere and restart a service, but I am not sure what. Thanks!

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  • Question about Partitioning

    - by Trent C
    I am looking to dual boot Windows 7 and Ubuntu 13.10. I have been using windows for work and school for over a year, and have about 100 gig of stored files (backed up of course) and some paid programs. Because of this, I really want my partitioning experience to go well. Unfortunately, I am running into a bit of an anomoly When I load GPart, I see that my sda drive is unallocated http://i.imgur.com/Hi2XhIr.png Whereas my sdb appears to contain all of the windows files and partitions, and make up my C: drive http://i.imgur.com/aaCOXje.png Is this going to be an issue, as all literature on dual boot installation references sda? How do I work around it? System Info: Lenovo IdeaPad Y570- 750GB HDD with 64GB SSD Processor: Intel® Core™ i7-2670QM CPU @ 2.20GHz × 8

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  • How can I transfer article content from old Joomla 1.5 site to new 2.5 site

    - by PaulHurleyuk
    I have an existing Joomla 1.5 site and am intending to wipe it and install a brand new 2.5 site. I will pick new plugins, template etc but would like to transfer the basic text / images of the articles on the 1.5 site to the new site. I am less concerned with categories and tags of those old articles, as they'll probably go in an 'old' category. I have several file and database backups of the 1.5 site. Has anyone done anything similar ? Are the two article db schemas similar enough to just transfer the data ?

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  • Basics of drawing in 2d with OpenGL 3 shaders

    - by davidism
    I am new to OpenGL 3 and graphics programming, and want to create some basic 2d graphics. I have the following scenario of how I might go about drawing a basic (but general) 2d rectangle. I'm not sure if this is the correct way to think about it, or, if it is, how to implement it. In my head, here's how I imagine doing it: t = make_rectangle(width, height) build general VBO, centered at 0, 0 optionally: t.set_scale(2) optionally: t.set_angle(30) t.draw_at(x, y) calculates some sort of scale/rotate/translate matrix (or matrices), passes the VBO and the matrix to a shader program Something happens to clip the world to the view visible on screen. I'm really unclear on how 4 and 5 will work. The main problem is that all the tutorials I find either: use fixed function pipeline, are for 3d, or are unclear how to do something this "simple". Can someone provide me with either a better way to think of / do this, or some concrete code detailing performing the transformations in a shader and constructing and passing the data required for this shader transformation?

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  • trying live-usb 12.04.1 image on an old desktop

    - by 213441265152351
    I am trying to load Ubuntu 12.04.1 32-bit desktop image on an old desktop computer. The system shows the initial menu, but after a while, I get an error like the one in the following two screenshots (it takes a few seconds to go from one to the other in the screen): I tried to load it using the different USB ports at the back of the computer, just in case, and I get basically the same error. Find another screenshot from another try: Any ideas what might be happening? NOTES: I checked the md5sum of the iso file to be e235b63c02644e219b7bf3668f479c9e *ubuntu-12.04.1-desktop-i386.iso. I did the 'Test' on the laptop where I created the USB drive, and it loads up correctly. The desktop computer in question is an old AMD Duron 1800MHz with 512MB RAM. I ran a memtest on the computer, and all went fine.

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  • How well do free-to-open-source-projects policies work in practice?

    - by Steve314
    In comparison with an open source license and requesting donations, is a free-for-open-source-projects (or free for non-commercial developers) closed source and otherwise commercial project likely to get more license fees? Or just to alienate potential users? Assume the project has value to programmers - I'm looking for generalizations here, though specific examples comparing existing projects will be very interesting. What I have in mind involves code generating programming utilities. And one issue I can think of, either way, is a near total inability to enforce any license restrictions. After all, I can't go around the internet demanding that everyone show me their source code just in case!

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  • High Availability for IaaS, PaaS and SaaS in the Cloud

    - by BuckWoody
    Outages, natural disasters and unforeseen events have proved that even in a distributed architecture, you need to plan for High Availability (HA). In this entry I'll explain a few considerations for HA within Infrastructure-as-a-Service (IaaS), Platform-as-a-Service (PaaS) and Software-as-a-Service (SaaS). In a separate post I'll talk more about Disaster Recovery (DR), since each paradigm has a different way to handle that. Planning for HA in IaaS IaaS involves Virtual Machines - so in effect, an HA strategy here takes on many of the same characteristics as it would on-premises. The primary difference is that the vendor controls the hardware, so you need to verify what they do for things like local redundancy and so on from the hardware perspective. As far as what you can control and plan for, the primary factors fall into three areas: multiple instances, geographical dispersion and task-switching. In almost every cloud vendor I've studied, to ensure your application will be protected by any level of HA, you need to have at least two of the Instances (VM's) running. This makes sense, but you might assume that the vendor just takes care of that for you - they don't. If a single VM goes down (for whatever reason) then the access to it is lost. Depending on multiple factors, you might be able to recover the data, but you should assume that you can't. You should keep a sync to another location (perhaps the vendor's storage system in another geographic datacenter or to a local location) to ensure you can continue to serve your clients. You'll also need to host the same VM's in another geographical location. Everything from a vendor outage to a network path problem could prevent your users from reaching the system, so you need to have multiple locations to handle this. This means that you'll have to figure out how to manage state between the geo's. If the system goes down in the middle of a transaction, you need to figure out what part of the process the system was in, and then re-create or transfer that state to the second set of systems. If you didn't write the software yourself, this is non-trivial. You'll also need a manual or automatic process to detect the failure and re-route the traffic to your secondary location. You could flip a DNS entry (if your application can tolerate that) or invoke another process to alias the first system to the second, such as load-balancing and so on. There are many options, but all of them involve coding the state into the application layer. If you've simply moved a state-ful application to VM's, you may not be able to easily implement an HA solution. Planning for HA in PaaS Implementing HA in PaaS is a bit simpler, since it's built on the concept of stateless applications deployment. Once again, you need at least two copies of each element in the solution (web roles, worker roles, etc.) to remain available in a single datacenter. Also, you need to deploy the application again in a separate geo, but the advantage here is that you could work out a "shared storage" model such that state is auto-balanced across the world. In fact, you don't have to maintain a "DR" site, the alternate location can be live and serving clients, and only take on extra load if the other site is not available. In Windows Azure, you can use the Traffic Manager service top route the requests as a type of auto balancer. Even with these benefits, I recommend a second backup of storage in another geographic location. Storage is inexpensive; and that second copy can be used for not only HA but DR. Planning for HA in SaaS In Software-as-a-Service (such as Office 365, or Hadoop in Windows Azure) You have far less control over the HA solution, although you still maintain the responsibility to ensure you have it. Since each SaaS is different, check with the vendor on the solution for HA - and make sure you understand what they do and what you are responsible for. They may have no HA for that solution, or pin it to a particular geo, or perhaps they have a massive HA built in with automatic load balancing (which is often the case).   All of these options (with the exception of SaaS) involve higher costs for the design. Do not sacrifice reliability for cost - that will always cost you more in the end. Build in the redundancy and HA at the very outset of the project - if you try to tack it on later in the process the business will push back and potentially not implement HA. References: http://www.bing.com/search?q=windows+azure+High+Availability  (each type of implementation is different, so I'm routing you to a search on the topic - look for the "Patterns and Practices" results for the area in Azure you're interested in)

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  • Lenovo z470 getting hot, after 12.04 install

    - by Rodrigo
    When I was using Windows 7 my notebook temperature was very good, it stayed very cool. After I installed 12.04, my notebook base is hot all the time, I cannot even put my hands on it for a long time. My notebook has a 2nd generation Intel i5 processor. I installed Jupiter and it shows 72 Degrees Celsius constantly. Anyone got a fix for this? I don't want to go back to windows but if I do not find any solution I will have to do it. I'd be very grateful for any help.

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  • Mouse and keyboard stop working after suspend or screensaver lock

    - by LEo
    If I leave the computer and let it run into screensaver and lock the screen, the mouse left click won't go back to work. If I suspend the computer, the keyboard won't get back to work. It started after upgrading to Ubuntu 11.04. Any tips to solve this problem? The follwing lines I got on dmesg after the problem happened [30536.564415] psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1 [30536.565725] psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1 [30536.568466] psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1 [30536.569790] psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1 [30536.571123] psmouse.c: TouchPad at isa0060/serio1/input0 lost sync at byte 1 [30536.571126] psmouse.c: issuing reconnect request and that after I tried to plug again my USB mouse: [31570.040088] usb 6-1: USB disconnect, address 2 [31573.490095] usb 6-1: new low speed USB device using uhci_hcd and address 3 [31573.687376] input: Microsoft Basic Optical Mouse as /devices/pci0000:00/0000:00:1d.1/usb6/6-1/6-1:1.0/input/input12 [31573.687544] generic-usb 0003:045E:0084.0002: input,hidraw0: USB HID v1.10 Mouse [Microsoft Basic Optical Mouse] on usb-0000:00:1d.1-1/input0

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  • Designing a simple snake A.I

    - by DillPixel
    I've looked at some stuff online regarding this specific topic, and a lot of the info that I read involved graphs and path finding. I really don't want to get involved in something too complex & out of my level, and also I don't need my snake to be that intelligent (it will be a large board with the snake not growing in size on every munch). How could you structure a simpler AI for the snake that gets the job done relatively well? I would be able to get the snake to move towards the food item correctly, but my issue is that I'm not sure how to deal with the snake colliding with itself. Say the snake has a look ahead, and it finds that its tail is in the way, it could change direction, but what happens next? Any ideas on how to tackle this? Should the snake build an instruction set from every square, or should it think on the go?

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  • Split screen and other issues on Ubuntu 11.10 with ATI graphics card

    - by garus
    Ever since updating my Ubuntu 11.04 to 11.10 I experience issues with graphics. The biggest is the "split screen" effect where my desktop is shifted to the right, resulting in having Unity bar in the middle of the screen. As shown here: http://i.imgur.com/I8nmZ.jpg This changes from boot to boot, sometimes it's on the left, sometimes in the middle. What I tried: Removing fglrx drivers completely Installing post-update version of them, but installation is broken ATM in the Ubuntu, so no go. No one is even trying to fix it (bug report https://bugs.launchpad.net/ubuntu/+source/nvidia-common/+bug/873058 and a couple of duplicates out there) Also using the open source "radeon" driver results in the same (I have a better successful boot ratio with this one, proprietary rarely lets me boot) Other artifacts are: serious screen tearing weird lines flickering in random places lagginess Did anyone experience that? My specs: Ubuntu 11.10 AMD Radeon HD 6950 1GB

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  • Render 3d object to 2d surface (embedded system)

    - by Martin Berger
    i am working on an embedded system of a sort, and in some free time i would like to test its drawing capabilities. System in question is ARM Cortex M3 microcontroller attached to EasyMX Stellaris board. And i have a small 320x240 TFT screen :) Now, i have some free time each day and i want to create rotating cube. Micro C PRO for ARM doesnt have 3d drawing capabilities, which means it must be done in software. From the book Introduction to 3D Game Programming with DirectX 10 i know matrix algebra for transformations but that is cool when you have DirectX to set camera right. I gues i could make 2d object to rotate, but how would i go with 3d one? Any ideas and examples are welcome. Although i would prefer advices. I'd like to understand this.

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  • Switching from abstract class to interface

    - by nischayn22
    I have an abstract class which has all abstract methods except one which constructs objects of the subclasses. Now my mentor asked me to move this abstract class to an interface. Having an interface is no problem except with the method used to construct subclass objects. Where should this method go now? Also, I read somewhere that interfaces are more efficient than abstract classes. Is this true? Here's an example of my classes abstract class Animal { //many abstract methods getAnimalobject(some parameter) { return //appropriate subclass } } class Dog extends Animal {} class Elephant extends Animal {}

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  • what do I need to do to get started with a website? [closed]

    - by omar
    I am a student and I have made websites for some companies before but now I would like to make a generic website for myself but dont know how to get started as I never had to deal with hosting or bandwidth before. I am looking to make a website that will provide users with information about me. In the future I might add things such as ordering or buying products but for now the idea is to provide information only. I was told not to go for any webhoster outside of Canada as I might risk the confidential integrity of my users or myself. I have no idea where to get started or what I need. I now also have to deal with possible security issues or security holes I may leave in my website creation... So my question here is: What is a good and reliable webhosting company that can be trusted to some degree?

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  • Using branches for a mini project or module of project: Good practice?

    - by TheLQ
    In my repo I have 3 closely related mini projects: 1 server and 2 clients. They are all quite small (<3 files each). Since they are so small and so closely related I just dropped them in folders in one single repo. However now that I know I can't clone a single directory in my VCS of choice (Mercurial), I'm considering splitting them up. However I'm confused about general best practice: Is it okay to put different small projects in different branches, or should they all go in different repos? I'm currently leaning towards branching since I can't easily splice out the file history of the different projects but then your using a feature in a way it wasn't meant to be used.

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  • No HDMI sound output on Thinkpad X1

    - by nickf
    I'm having problems getting my sound to output via HDMI to my TV. When I go to Sound Settings, the HDMI device does not appear. ~$ aplay -l **** List of PLAYBACK Hardware Devices **** card 0: PCH [HDA Intel PCH], device 0: CONEXANT Analog [CONEXANT Analog] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 3: HDMI 0 [HDMI 0] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 7: HDMI 1 [HDMI 1] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: PCH [HDA Intel PCH], device 8: HDMI 2 [HDMI 2] Subdevices: 1/1 Subdevice #0: subdevice #0 I don't know if the video information is helpful, but anyway: ~$ sudo lshw -C video *-display description: VGA compatible controller product: 2nd Generation Core Processor Family Integrated Graphics Controller vendor: Intel Corporation physical id: 2 bus info: pci@0000:00:02.0 version: 09 width: 64 bits clock: 33MHz capabilities: msi pm vga_controller bus_master cap_list rom configuration: driver=i915 latency=0 resources: irq:46 memory:d0000000-d03fffff memory:c0000000-cfffffff ioport:5000(size=64) Any suggestions for me?

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  • How do I learn algorithms and data structures?

    - by sushil bharwani
    this is in continuation to my previous question where i asked is it necessary to learn algorithm and datastructures. I feel yes it is. Now when i work in a enviornment where i wont ever get the chance to learn it by experimenting or practically or in any assignment. What is the right approach like the right books, right kind of problems, right kind of resources that i can go through to give six months or a year or two to learn it. And also mould my mind in a way that it can relate problems to datastructures and algos.

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  • What would most games benefit from having?

    - by Phil
    I think I've seen "questions" like this on stackoverflow but sorry if I'm overstepping any bounds. Inspired by my recent question and all the nice answers (Checklist for finished game?) I think every gamedev out there has something he/she thinks that almost every game should have. That knowledge is welcome here! So this is probably going to be an inspirational subjective list of some sorts and the point is that anyone reading this question will see a point or two that they've overlooked in their own development and might benefit from adding. I think a good example might be: "some sort of manual or help section. Of course it should be proportional to how advanced the game is. Some users won't need it and won't go looking for it but the other ones that do will become very frustrated if they can't remember how to do something specific that should be in the manual". A bad example might be "good gameplay". Of course every game benefits from this but the answer is not very helpful.

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  • Recommended hardware for developing ios games?

    - by Matthew
    I know you have to have mac os x to use xcode and thus to develop/compile apps for the iphone. And I'm not exactly wanting to go the hackintosh way, so I'm looking at buying a used mac. What specs are recommended. If I buy a cheap mac mini that has only 1gb of ram would that be enough? (I'm not talking about using that to create the graphics/audio, I'll use my normal windows/ubuntu pc for that). I'm just talking about being able to use xcode and write applications. I'm trying to spend the least amount I can without running into problems developing the app.

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  • Removing AppPrincipals from Office365

    - by Sahil Malik
    SharePoint, WCF and Azure Trainings: more information So here is an annoying issue. If I have your AppPrincipal and secret, I can party as you! But as we go through our usual dev cycles, we create these ApplicationIDs. Hell Visual Studio will create them for us, to make things easy!The problem is, many a developer, and some a ITOgre, may leave these AppPrincipalIds sitting there and not clean them up when they are done playing. You can look for currently registered App Principals at https://yourtenant/_layouts/15/appprincipals.aspx The problem is, that URL shows you App Principals registered AND currently in use. Currently NOT in use App Principals are NOT shown on that page. The same issue applies on premises also, even though here I am talking specifically about Office 365. Getting rid of these in On-Prem is easy, just use the Object model (server side). Read full article ....

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  • Performance triage

    - by Dave
    Folks often ask me how to approach a suspected performance issue. My personal strategy is informed by the fact that I work on concurrency issues. (When you have a hammer everything looks like a nail, but I'll try to keep this general). A good starting point is to ask yourself if the observed performance matches your expectations. Expectations might be derived from known system performance limits, prototypes, and other software or environments that are comparable to your particular system-under-test. Some simple comparisons and microbenchmarks can be useful at this stage. It's also useful to write some very simple programs to validate some of the reported or expected system limits. Can that disk controller really tolerate and sustain 500 reads per second? To reduce the number of confounding factors it's better to try to answer that question with a very simple targeted program. And finally, nothing beats having familiarity with the technologies that underlying your particular layer. On the topic of confounding factors, as our technology stacks become deeper and less transparent, we often find our own technology working against us in some unexpected way to choke performance rather than simply running into some fundamental system limit. A good example is the warm-up time needed by just-in-time compilers in Java Virtual Machines. I won't delve too far into that particular hole except to say that it's rare to find good benchmarks and methodology for java code. Another example is power management on x86. Power management is great, but it can take a while for the CPUs to throttle up from low(er) frequencies to full throttle. And while I love "turbo" mode, it makes benchmarking applications with multiple threads a chore as you have to remember to turn it off and then back on otherwise short single-threaded runs may look abnormally fast compared to runs with higher thread counts. In general for performance characterization I disable turbo mode and fix the power governor at "performance" state. Another source of complexity is the scheduler, which I've discussed in prior blog entries. Lets say I have a running application and I want to better understand its behavior and performance. We'll presume it's warmed up, is under load, and is an execution mode representative of what we think the norm would be. It should be in steady-state, if a steady-state mode even exists. On Solaris the very first thing I'll do is take a set of "pstack" samples. Pstack briefly stops the process and walks each of the stacks, reporting symbolic information (if available) for each frame. For Java, pstack has been augmented to understand java frames, and even report inlining. A few pstack samples can provide powerful insight into what's actually going on inside the program. You'll be able to see calling patterns, which threads are blocked on what system calls or synchronization constructs, memory allocation, etc. If your code is CPU-bound then you'll get a good sense where the cycles are being spent. (I should caution that normal C/C++ inlining can diffuse an otherwise "hot" method into other methods. This is a rare instance where pstack sampling might not immediately point to the key problem). At this point you'll need to reconcile what you're seeing with pstack and your mental model of what you think the program should be doing. They're often rather different. And generally if there's a key performance issue, you'll spot it with a moderate number of samples. I'll also use OS-level observability tools to lock for the existence of bottlenecks where threads contend for locks; other situations where threads are blocked; and the distribution of threads over the system. On Solaris some good tools are mpstat and too a lesser degree, vmstat. Try running "mpstat -a 5" in one window while the application program runs concurrently. One key measure is the voluntary context switch rate "vctx" or "csw" which reflects threads descheduling themselves. It's also good to look at the user; system; and idle CPU percentages. This can give a broad but useful understanding if your threads are mostly parked or mostly running. For instance if your program makes heavy use of malloc/free, then it might be the case you're contending on the central malloc lock in the default allocator. In that case you'd see malloc calling lock in the stack traces, observe a high csw/vctx rate as threads block for the malloc lock, and your "usr" time would be less than expected. Solaris dtrace is a wonderful and invaluable performance tool as well, but in a sense you have to frame and articulate a meaningful and specific question to get a useful answer, so I tend not to use it for first-order screening of problems. It's also most effective for OS and software-level performance issues as opposed to HW-level issues. For that reason I recommend mpstat & pstack as my the 1st step in performance triage. If some other OS-level issue is evident then it's good to switch to dtrace to drill more deeply into the problem. Only after I've ruled out OS-level issues do I switch to using hardware performance counters to look for architectural impediments.

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