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  • If a library doesn't provide all my needs, how should I proceed?

    - by 9a3eedi
    I'm developing an application involving math and physics models, and I'd like to use a Math library for things like Matrices. I'm using C#, and so I was looking for some libraries and found Math.NET. I'm under the impression, from past experience, that for math, using a robust and industry-approved third party library is much better than writing your own code. It seems good for many purposes, but it does not provide support for Quaternions, which I need to use as a type. Also, I need some functions in Vector and Matrix that also aren't provided, such as rotation matrices and vector rotation functions, and calculating cross products. At the same time, it provides a lot of functions/classes that I simply do not need, which might mean a lot of unnecessary bloat and complexity. At this rate, should I even bother using the library? Should I write my own math library? Or is it a better idea to stick to the third party library and somehow wrap around it? Perhaps I should make a subclass of the Matrix and Vector type of the library? But isn't that considered bad style? I've also tried looking for other libraries but unfortunately I couldn't find anything suitable.

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  • How do you KISS?

    - by Conor
    The KISS principle is a highly quoted design mantra. The aim of this principle is to stamp out unnecessary complexity on a project. This is a good thing, saving time, energy and money. It can lead to a relatively stress free implementation and a simple, elegant, maintainable end product. A lot of discussion on KISS provides mechanisms to simplify requirements, design and implementation. Things that spring to mind include: avoid scope creep; simple obvious design and code; minimal run-time dependencies; refactoring to maintain simplicity; etc. However there are a lot of implicit things that we do to KISS. Examples: small team sizes; minimal management layers; tidy desk; mastery of a single IDE; clear concise error messages; scripts to automate/encapsulate tasks; etc Why KISS practices do you apply? How have they been of benefit? I'm especially interested in non-obvious practices.

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  • The year ahead, 2011.

    - by andrewstopford
    When I look back at last years look at 2010 my blogging rate has not changed much (I suspect this is largely down to using Twitter a lot) but my interests this year have developed a lot further. My view on 2010 would be that Microsoft would commit more to OSS, while I wanted to see more hires from that audience and more projects on Outercurve foundation instead there has been support for JQuery and Gems (aka NuGet). I would love to see more from Microsoft on the OSS front in 2011, Outercurve could become like the Apache foundation with enough support. Staying on the Microsoft front I predict that 2011 will bring the following. C# 5.0 will go RTM (still no MOP though) The next release of VS will go alpha or early beta MS MVC 4.0 (I think by Mix time) and maybe this release will get a command line. I also suspect that Microsoft will want to target the tablet market with WP7 in 2011 (Mix 2011 maybe...). I also predict the following Java will fork with Apache\Google. Oracle will then take them to court and the whole thing will boil right through 2011 (Java have had enough court cases, come on guys). Java and the JVM will sadly not move forward at all in 2011. Android will cause Apple a serious headache, both the smartphone and tablet market will see figures cut from Apple share. By the end of 2011 the current 70% apple market share will be 40-50%. As the features, performance and price of Android devices gets ever better Apple will be left out in the open. Lastly after 7 years I intend to move this blog away from weblogs. In 2011 I will be exploring Java, Ruby\Rails and Android and such subjects don't make sense to talk about it here. See you in 2011.

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  • PHP frameworks - should I use them?

    - by 30secondstosam
    First of all let me explain who I am: I am a PHP Developer working for a company developing their CMS which handles online stores, data feeds and other content like blogs. I have been programming for 6 years and 4 of those have been in PHP. (I used to be a C# developer). My question is regarding PHP frameworks. I see so many jobs asking for zend, cakephp and other MVC types of frameworks. However, even as an experienced developer I have never used a PHP framework. Should I start learning? If so where do I even start as there are so many. I am about to re-write so much of my work's CMS and I'm wondering whether I could help myself a lot by using a framework. What do people think? Considering I will be re-writing a lot of the online store stuff... I am experienced in OO and I have used the .NET framework in the past. Thanks in advance for the replies.

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  • guidline for promoting a web forum or portal

    - by Hafiz
    I am a web application developer, have developed a lot of sites, portal and apps for clients. Now I want to have own such sites that with which I can do business. But I don't know what are steps to do so. What I know is make a site or portal. But what after that? There are lot of people having so much traffic on sites built with some simple open source. Many of them are forums. I also wanted to start a forum and a web portal. I can develop that or can have open source. But what after that? Content entry and SEO? Is it all to promote a portal or site? Do SEO nowadays work ? or it is all about marketing and advertising? I have no idea about that so please tell what you guys suggest. thanks for every one's opinion in advance.

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  • How to understand computer science as a whole?

    - by MrCellophane
    I am a college student in Computer Science, I have been studying CS for a long time. But even till today, I still feel so confused about a lot of things. First of all, I have solid foundation in alg, data structure, and OOP, but I don't have a clear understanding of the whole system of the subject. I studied database, alg, data structure, OOP, network, software engineering, OS, and a lot of courses. I know what they are, but I don't know how to connect them together. Is there a way to have a clear understanding of the architecture of the subject? And is there a way to know what technology is used to do what? For example, in interviews, when people ask me alg, data str, Java, OS or any other specific field, I could answer, but when they ask some other very general about the field, I have no idea. Well, I know my question maybe a little bit confusing, but what my situation is I don't even know how to ask a clear question. I don't know my question, it's totally a mess in my head. Is there a way to make it clear?

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  • Shooting Print Quality Pictures with a Camera Phone [Video]

    - by Jason Fitzpatrick
    Camera phones get a lot of grief for being underpowered but in this video tutorial the crew at SLR Lounge shows how basic technique and a good eye overcome all. Last year over at the photo blog FStoppers they put together a video showing off how you could use the iPhone as a fashion camera–essentially arguing that the camera wasn’t as important as the photographer. A lot of people said “Well yeah, but you had professional models and thousands of dollars in lighting equipment!” in reaction to the video. In turn the crew at SLR Lounge decided to make their own video showing that using only an iPhone camera and two reflectors (as well as an attractive but informal model). It of course helps to have some side kicks to help hold up your reflectors but the point still stands about modern camera phones being perfectly capable of good photos. The SLR Lounge iPhone Photo Shoot – A Follow Up Tribute to The FStoppers [YouTube] What is a Histogram, and How Can I Use it to Improve My Photos?How To Easily Access Your Home Network From Anywhere With DDNSHow To Recover After Your Email Password Is Compromised

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  • Web application design with distributed servers

    - by Bonn
    I want to build a web application/server with this structure: main-server sub-server transaction-server (create, update, delete) view-server (view, search) authentication-server documents-server reporting-server library-server e-learning-server The main-server acts as host server for sub-server. I can add many sub-servers and connect it to main-server (via plug-play interface maybe), then it can begin querying data from another sub-servers (which has been connected to the main-server). The sub-servers can be anywhere as long as connected to internet. The main-server can manage all sub-servers which are connected to it (query data, setting permission between sub-servers, etc). The purpose is simple, the web application will be huge as the company grows, so I want to distribute it into small connected plug-able servers. My question is, does the structure above already have a standardized method? or are there any different views? what are the technologies needed? I need a lot of researches before the execution plan begin. thanks a lot.

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  • Groovy Refactoring in NetBeans

    - by Martin Janicek
    Hi guys, during the NetBeans 7.3 feature development, I spend quite a lot of time trying to get some basic Groovy refactoring to the game. I've implemented find usages and rename refactoring for some basic constructs (class types, fields, properties, variables and methods). It's certainly not perfect and it will definitely need a lot fixes and improvements to get it hundred percent reliable, but I need to start somehow :) I would like to ask all of you to test it as much as possible and file a new tickets to the cases where it doesn't work as expected (e.g. some occurrences which should be in usages isn't there etc.) ..it's really important for me because I don't have real Groovy project and thus I can test only some simple cases. I can promise, that with your help we can make it really useful for the next release. Also please be aware that the current version is focusing only on the .groovy files. That means it won't find any usages from the .java files (and the same applies for finding usages from java files - it won't find any groovy usages). I know it's not ideal, but as I said.. we have to start somehow and it wasn't possible to make it all-in-one, so only other option was to wait for the NetBeans 7.4. I'll focus on better Java-Groovy integration in the next release (not only in refactoring, but also in navigation, code completion etc.) BTW: I've created a new component with surprising name "Refactoring" in our bugzilla[1], so please put the reported issues into this category. [1] http://netbeans.org/bugzilla/buglist.cgi?product=groovy;component=Refactoring

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  • As a developer, how do I learn sales? [closed]

    - by Dan Abramov
    I quit the company I was working for to pursuit an opportunity as a startup, and I believe in our product. I'm sure it's going to be great if we attract some customers first to keep going. (I don't want funding.) Our product is targeted at private schools and courses, and helps organize the mess other LMSs introduce. The problem is, our team is basically just me and I have very little idea about sales and marketing. I can do reasonably good copywriting but I'm sure I can do better—and being nervous or too techy in a real world conversation with the client doesn't help. I want to get better, in fact, a lot better at negotiating with clients and pitching my product. I did look for some “sales articles” on the web, and a lot of what I found is plain bullshit on SEO-engineered websites promoting books or $5000 courses. What I need instead is a developer's perspective on how to sale a product you think is great. What are typical programmer's mistakes and misconceptions about sales, and how to avoid them? How do you evolve into a reasonably great salesman? I can't believe it's in the mindset and unlearnable. Your own experience, combined with great articles available on the web is most welcome. To Future Readers The question got closed because it is not a good fit for this site. I found some helpful tips in a similar question asked on a sister StackExchange site about startups: I'm a terrible salesperson. What can I do about it?

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  • Who should be the architect in an agile project?

    - by woni
    We are developing the agile way for a few months now and I have some troubles understanding the agile manifesto as interpreted by my colleagues. The project we are developing is a framework for future projects and will be reused many times in the next years. Code is only written to fulfill the needs of the current user story. The product owner tells us what to do, but not how to do it. What would be right, in my opinion, because he is not implicitly a programmer. The project advanced and in my eyes it messed up a little bit. After I recognized an assembly that was responsible for 3 concerns (IoC-Container, communication layer and project internal things), I tried to address this to my colleagues. They answered that this would be the result of applying YAGNI, because know one told them to respect that functionalities have to be split up in different assemblies for further use. In my opinion no one has to tell us that we should respect the Separation of Concerns principle. On the other side, they mentioned to prefer YAGNI over SoC because it is less effort to implement and therefore faster and cheaper. We had changing requirements a lot at the beginning of the project and ended up in endless refactoring sessions, because to much has to be adapted. Is it better to make such rather simple design decisions up front, even there is no need in the current situation, or do we have to change a lot in the later progress of the project?

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  • Setting up podcasting for a non-tech user

    - by Force Flow
    I have a user who wants to start making podcasts, but they only have basic skills when it comes to technology. So, I was trying to get a process together that would be easy for them to follow. To upload files (the mp3's and rss feed files), I have an explorer shortcut for their FTP space. To record the podcast, I was going to either use audacity or PodProducer. For the RSS feed, I was looking for a podcast RSS generator of some sort. In my search for this, I've come across a lot of dead links and a lot of paid tools, so I haven't come up with anything too useful. Is there a free, reliable webservice or windows-based tool available that folks like to use?

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  • Architecture a for a central renderer rather than self-rendering

    - by The Communist Duck
    For the architectural side of rendering, there's two main ways: having each object render itself, and having a single renderer which renders everything. I'm currently aiming for the second idea, for the following reasons: The list can be sorted to only use shaders once. Else each object would have to bind the shader, because it's not sure if it's active. The objects could be sorted and grouped. Easier to swap APIs. With a few macro lines, it can be easy to swap between a DirectX renderer and an OpenGL renderer (not a reason for my project, but still a good point) Easier to manage rendering code Of course, if anyone has strong recommendations for the first method, I will listen to them. But I was wondering how make this work. First idea The renderer has a list of pointers to the renderable components of each entity, which register themselves on RenderCompoent creation. However, I'm worrying that this may end up as a lot of extra pointer weight. But I can sort the list of pointers every so often. Second idea The entire list of entities is passed to the renderer each render call. The renderer then sorts the list (each call, or maybe once?) and gets what it wants. That's a lot of passing and/or sorting, however. Other ideas ??? PROFIT Anyone got ideas? Thank you.

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  • Outlook Prompting for password from Exchange server in domain environment

    - by jherlitz
    We are running exchange 2007 in a domain environment. We have mostly outlook 2003 clients, but in process of upgrading to outlook 07 over the next couple of weeks. Some users (both 03 & 07) are constantly getting prompted to enter their credentials. The 07 client I was working on this morning states "needs password" in the bottom right corner. It is also speratic, as it will work fine most days but not some other days. The user I was working with this morning, has been working fine. Now it just started up today. I have been googling this, and have found lot's of information, but nothing that has helped yet. A lot of the information out there is for outlook users using a external email account. Being they already logged into the domain, these users should not be prompted for their credentials. Any advice out there?

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  • crippling repeating "pciehp card not present" notifications

    - by Nanne
    When using ubuntu (12.04, both installed and on a live usb) I get a lot of these messages: pciehp 0000:00:1c.5:pcie04: Card not present on Slot(37) pciehp 0000:00:1c.5:pcie04: Card present on Slot(37) And with a lot I mean about 20 per second. This has a crippling effect, and I would like to get rid of it :) The computer is a packard bell easynote BG48-U-100 DC. I tip I picked up from some fedora/redhat error here was to look at lspci -vnn. I have pasted the part about "00:1c.5" here: http://pastebin.com/0sfsiqW2 For what good it may do, here is the lsmod of my machine: http://pastebin.com/DQZy1kAL From that first pastebin I think to conclude that it has to do with the module shpchp, which seems to me (aka: google) to have something to do with ACPI. That's as far as I've come in disecting this. Can anyone help me along further? What can I do, check etc? I did see this topic but my intentions are not to surpress the error message: I know how to do this (from that topic ;) ), but I'm looking for a real sollution. Finding the problem on the internet does suspect me to believe it is neither an ubuntu specific nor a packard-bell specific problem.If you google the problem it seems that is present on several other distribution/hardware combo's as well, and it looks like the advice is to remove one of the drivers? I have no clue as to which driver I should look at and and what would be the effect of just removing it. I have seen this topic which is old-ish, but describes my problem and is about a similar computer. The solution in this topic was to compile a new kernel using a spanish guide, which seems a bit extreme to me, so I'm kinda hoping for a better solution than that.

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  • Publishing a game -- any way to target both WP7 and Win8 Store?

    - by Rei Miyasaka
    I'm at a dilemma which seems should soon become an important issue for a lot of developers. If I build a game in XNA, I won't be able to publish it on the Windows 8 Store, as it would be a classic application -- and classic applications can't be sold on the store. If I build a game in Metro DirectX, I would be able to sell it on the Store, but porting it to Windows Phone would involve porting it to Reach XNA, which in fact would likely involve more effort even than porting to OS X or Android -- both of which support C++. Of all the WinRT API that is supported on C++/JS/.NET, DirectX can only be programmed from C++. It's also unlikely that Microsoft will update Windows 7 or Vista to support the new DirectX features, although that would make the Metro DirectX the first new version of DirectX to stop supporting the immediate predecessor OS. If I build a game in Pre-Win8 DirectX 9/10/11, I won't be able to sell it on the Windows Store or Windows Phone, but I could sell it on something like Steam. It would also involve the most amount of manual plumbing. In fact, DirectWrite, despite being part of DirectX 11, doesn't talk to Direct3D. I'm getting really tired of all these restrictions -- artificial and otherwise -- and I'm coming to a point where I'm considering switching to a platform with a less fragmented API, like Android or Mac/iOS. As far as bringing a game into market goes, excluding the actual market share of any platforms that I might consider, what other factors would help me in making a decision? Just a few years ago this question was a lot easier to answer: if you were primarily concerned with Windows platforms, all you had to answer was whether you wanted DirectX, XNA, or something like SlimDX. If you made the wrong decision, no biggie -- all you really would have lost is XBox and the fairly small Windows Phone market.

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  • Do you keep your ideas secret? and why?

    - by MainMa
    I believe any programmer has several ideas that she/he considers as innovative or at least valuable. It may be an idea of a new product which will make this world better or a new development approach, etc. But a great idea must be implemented and promoted/advertised. This requires a lot of work (proofs of concept, prototypes, technology previews, etc.) and a lot of money (appropriate advertisement, marketing, etc.). So months later, the idea stays in our heads, but nothing else is done, because it's difficult, long and expensive, sometimes even impossible for a single developer. On the other hand, it would be painful to share our ideas, and see a medium-size company which has enough resources making something useful from it and having success and money. So what do you do with your ideas you can hardly implement or patent? Do you talk freely about them in discussion boards and with other developers? Do you keep them like a precious thing without never talking about them to anybody? If you keep your ideas, why are you doing so? Is it just because you hope that one day, you will be able to implement them and have a huge success, while you know very well by experience that it's an utopia?

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  • How to target just one search engine and optimise for that

    - by mickburkejnr
    I've been dabbling with SEO a lot in the last 6 months, and one thing that has surprised me is the disparity between Google and Bing in the way they deliver results. A website ranked for a specific keyword/phrase on Google may rank 3rd on the first page, but using the same keyword/phrase on Bing will display the same website but ranked 15th for the exact same keyword/phrase. I came up with the idea to increase traffic to my website by targetting Bing instead of Google for several reasons. The biggest one is that while it's not the biggest search provider, people still use it, and I feel that if other websites have been "neglected" and not optimised for Bing my website would stand a better chance of getting near the top of their search rankings. The question is though how would I do this? A lot of the SEO advice on the internet is generic, but I can't help feeling it's Google orientated for obvious reasons. How could I optimise my website to be Bing friendly, rather than Google friendly? I know it sounds like suicide as I'm taking myself out of the Google mindset, but I feel it could work wonders for traffic to the site.

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  • Inheritance vs containment while extending a large legacy project

    - by Flot2011
    I have got a legacy Java project with a lot of code. The code uses MVC pattern and is well structured and well written. It also has a lot of unit tests and it is still actively maintained (bug fixing, minor features adding). Therefore I want to preserve the original structure and code style as much as possible. The new feature I am going to add is a conceptual one, so I have to make my changes all over the code. In order to minimize changes I decided not to extend existing classes but to use containment: class ExistingClass { // .... existing code // my code adding new functionality private ExistingClassExtension extension = new ExistingClassExtension(); public ExistingClassExtension getExtension() {return extension;} } ... // somewhere in code ExistingClass instance = new ExistingClass(); ... // when I need a new functionality instance.getExtension().newMethod1(); All functionality that I am adding is inside a new ExistingClassExtension class. Actually I am adding only these 2 lines to each class that needs to be extended. By doing so I also do not need to instantiate new, extended classes all over the code and I may use existing tests to make sure there is no regression. However my colleagues argue that in this situation doing so isn't a proper OOP approach, and I need to inherit from ExistingClass in order to add a new functionality. What do you think? I am aware of numerous inheritance/containment questions here, but I think my question is different.

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  • How can I make permanent death in a MUD seem acceptable and fair to players?

    - by Luke Laupheimer
    I have considered writing a MUD for years, and I have a lot of ideas my friends think are really cool (and that's how I'd hope to get anywhere -- word of mouth). Thing is, there's one thing I have always wanted, that my friends and strangers hated: permanent death. Now, the emotional response I get to this is visceral revulsion, every time. I'm pretty sure I am the only person that wants this, or if I'm not, I'm a tiny minority. Now, the reason I want it is because I want the actions of the players to matter. Unlike a lot of other MUDs, which have a set of static city-states and social institutions etc, I want the things my players do, should I get any, to actually change the situation. And that includes killing people. If you kill someone, you didn't send them to time out, you killed them. What happens when you kill people? They go away. They don't come back in half an hour to smack talk you some more. They're gone. Forever. By making death non-permanent, you make death not matter. It would be similar if a climax to a character's arc is getting a speeding ticket. It cheapens it. Non-permanent death cheapens death. How can I: 1) Convince my players (and random people!) that this is actually a good idea?, or 2) Find some other way to make death and violence matter as much as it does in real life (except within the game, of course) sans character deletion? What alternatives are there out there?

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  • How to manage and estimate unstructured requirements received from customers

    - by user20358
    A lot of the times I receive a software system's requirements from our customers in a very unstructured format. It is usually a bunch of "product development" guys from the customer's who come up with these "proposed solutions" to the business problems they have. While they are the experts at the business domain, a lot of the times they don't have the solutions right. This results in multiple versions of the same requirement mixing up of two requirements into one a few versions of the requirement later down the line, the requirements which were combined together get separated out again, each taking with it some of the new additions How do you work with such requirements coming in and sort them out into proper use cases and before development begins? What tools can we use to track a particular requirement's history, from the first time it was conceived till the time it gets crystallized into a proper use case? Estimating work against requirements received in such a fashion is a nightmare which ends up in making mistakes in understanding the requirement correctly and estimating the effort against it correctly. Any tips, tools, tricks to make this activity more manageable? I'm just trying to get some insights from someone more experienced than I am in requirements management and effort estimation.

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  • Entity system in Lua, communication with C++ and level editor. Need advice.

    - by Notbad
    Hi!, I know this is a really difficult subject. I have been reading a lot this days about Entity systems, etc... And now I'm ready to ask some questions (if you don't mind answering them) because I'm really messed. First of all, I have a 2D basic editor written in Qt, and I'm in the process of adding entitiy edition. I want the editor to be able to receive RTTI information from entities to change properties, create some logic being able to link published events to published actions (Ex:A level activate event throws a door open action), etc... Because all of this I guess my entity system should be written in scripting, in my case Lua. In the other hand I want to use a component based design for my entities, and here starts my questions: 1) Should I define my componentes en C++? If I do this en C++ won't I loose all the RTTI information I want for my editor?. In the other hand, I use box2d for physics, if I define all my components in script won't it be a lot of work to expose third party libs to lua? 2) Where should I place the messa system for my game engine? Lua? C++?. I'm tempted to just have C++ object to behave as servers, offering services to lua business logic. Things like physics system, rendering system, input system, World class, etc... And for all the other things, lua. Creation/Composition of entities based on components, game logic, etc... Could anyone give any insight on how to accomplish this? And what aproach is better?. Thanks in advance, HexDump.

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  • Programming habits, patterns, and standards that have developed out of appeal to tradition/by mistake? [closed]

    - by user828584
    Being self-taught, the vast majority of what I know about programming has come from reading other peoples' code on websites like this. I'm starting to wonder if I've developed bad or otherwise pointless habits from other people, or even just made invalid assumptions. For example, in javascript, void 0 is used in a lot of places, and until I saw this, I just assumed it was necessary and that 0 had some significance. Also, the http header, referer is misspelled but hasn't been changed because it would break a lot of applications. Also mentioned in Code Complete 2: The architecture should describe the motivations for all major decisions. Be wary of “we’ve always done it that way” justifications. One story goes that Beth wanted to cook a pot roast according to an award-winning pot roast recipe handed down in her husband’s family. Her husband, Abdul, said that his mother had taught him to sprinkle it with salt and pepper, cut both ends off, put it in the pan, cover it, and cook it. Beth asked, “Why do you cut both ends off?” Abdul said, “I don’t know. I’ve always done it that way. Let me ask my mother.” He called her, and she said, “I don’t know. I’ve always done it that way. Let me ask your grandmother.” She called his grandmother, who said, “I don’t know why you do it that way. I did it that way because it was too big to fit in my pan.” What are some other examples of this?

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  • Have You Checked Our BI Publisher Channel at Youtube ?

    - by kanichiro.nishida
    These days, more and more people watching video online rather than reading. Steve Jobs once said people don’t read anymore. Well, I love books and still read a lot either on books, magazine, iPad, MacbookPro, or whatever the medium shows me letters! But I have to admit, sometimes it’s much easier to understand especially something like How-To by just watching video clips than reading it. And this is why we started our BI Publisher Channel at Youtube last summer. Since then we have uploaded over 10 video clips so far and and now we’re gearing up to add more and more clips. Now, we’re in a middle of finishing up our work for the next 11G 1st patchset release, which should be coming soon and will have a lot of great new features that I can’t wait to talk to you guys about. And of course we’re preparing introduction and How-Top clips. So please subscribe the BI Publisher channel now if you haven’t done yet and stay tuned for the new clips! http://www.youtube.com/user/bipublisher Also, we’d love to hear your comments for each clip, so please don’t forget leaving your comments there after you watch!

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  • The Importance of Fully Specifying a Problem

    - by Alan
    I had a customer call this week where we were provided a forced crashdump and asked to determine why the system was hung. Normally when you are looking at a hung system, you will find a lot of threads blocked on various locks, and most likely very little actually running on the system (unless it's threads spinning on busy wait type locks). This vmcore showed none of that. In fact we were seeing hundreds of threads actively on cpu in the second before the dump was forced. This prompted the question back to the customer: What exactly were you seeing that made you believe that the system was hung? It took a few days to get a response, but the response that I got back was that they were not able to ssh into the system and when they tried to login to the console, they got the login prompt, but after typing "root" and hitting return, the console was no longer responsive. This description puts a whole new light on the "hang". You immediately start thinking "name services". Looking at the crashdump, yes the sshds are all in door calls to nscd, and nscd is idle waiting on responses from the network. Looking at the connections I see a lot of connections to the secure ldap port in CLOSE_WAIT, but more interestingly I am seeing a few connections over the non-secure ldap port to a different LDAP server just sitting open. My feeling at this point is that we have an either non-responding LDAP server, or one that is responding slowly, the resolution being to investigate that server. Moral When you log a service ticket for a "system hang", it's great to get the forced crashdump first up, but it's even better to get a description of what you observed to make to believe that the system was hung.

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