Search Results

Search found 9779 results on 392 pages for 'ezine articles'.

Page 379/392 | < Previous Page | 375 376 377 378 379 380 381 382 383 384 385 386  | Next Page >

• Seven Random Thoughts on JavaOne

  - by HecklerMark

  As most people reading this blog may know, last week was JavaOne. There are a lot of summary/recap articles popping up now, and while I didn't want to just "add to pile", I did want to share a few observations. Disclaimer: I am an Oracle employee, but most of these observations are either externally verifiable or based upon a collection of opinions from Oracle and non-Oracle attendees alike. Anyway, here are a few take-aways: The Java ecosystem is alive and well, with a breadth and depth that is impossible to adequately describe in a short post...or a long post, for that matter. If there is any one area within the Java language or JVM that you would like to - or need to - know more about, it's well-represented at J1. While there are several IDEs that are used to great effect by the developer community, NetBeans is on a roll. I lost count how many sessions mentioned or used NetBeans, but it was by far the dominant IDE in use at J1. As a recent re-convert to NetBeans, I wasn't surprised others liked it so well, only how many. OpenJDK, OpenJFX, etc. Many developers were understandably concerned with the change of sponsorship/leadership when Java creator and longtime steward Sun Microsystems was acquired by Oracle. The read I got from attendees regarding Oracle's stewardship was almost universally positive, and the push for "openness" is deep and wide within the current Java environs. Few would probably have imagined it to be this good, this soon. Someone observed that "Larry (Ellison) is competitive, and he wants to be the best...so if he wants to have a community, it will be the best community on the planet." Like any company, Oracle is bound to make missteps, but leadership seems to be striking an excellent balance between embracing open efforts and innovating in competitive paid offerings. JavaFX (2.x) isn't perfect or comprehensive, but a great many people (myself included) see great potential, are developing for it, and are really excited about where it is and where it may be headed. This is another part of the Java ecosystem that has impressive depth for being so new (JavaFX 1.x aside). If you haven't kicked the tires yet, give it a try! You'll be surprised at how capable and versatile it is, and you'll probably catch yourself smiling while coding again.  :-) JavaEE is everywhere. Not exactly a newsflash, but there is a lot of buzz around EE still/again/anew. Sessions ranged from updated component specs/technologies to Websockets/HTML5, from frameworks to profiles and application servers. Programming "server-side" Java isn't confined to the server (as you no doubt realize), and if you still consider JavaEE a cumbersome beast, you clearly haven't been using the last couple of versions. Download GlassFish or the WebLogic Zip distro (or another JavaEE 6 implementation) and treat yourself. JavaOne is not inexpensive, but to paraphrase an old saying, "If you think that's expensive, you should try ignorance." :-) I suppose it's possible to attend J1 and learn nothing, but you'd have to really work at it! Attending even a single session is bound to expand your horizons and make you approach your code, your problem domain, differently...even if it's a session about something you already know quite well. The various presenters offer vastly different perspectives and challenge you to re-think your own approach(es). And finally, if you think the scheduled sessions are great - and make no mistake, most are clearly outstanding - wait until you see what you pick up from what I like to call the "hallway sessions". Between the presentations, people freely mingle in the hallways, go to lunch and dinner together, and talk. And talk. And talk. Ideas flow freely, sparking other ideas and the "crowdsourcing" of knowledge in a way that is hard to imagine outside of a conference of this magnitude. Consider this the "GO" part of a "BOGO" (Buy One, Get One) offer: you buy the ticket to the "structured" part of JavaOne and get the hallway sessions at no additional charge. They're really that good. If you weren't able to make it to JavaOne this year, you can still watch/listen to the sessions online by visiting the JavaOne course catalog and clicking the media link(s) in the right column - another demonstration of Oracle's commitment to the Java community. But make plans to be there next year to get the full benefit! You'll be glad you did. All the best,Mark P.S. - I didn't mention several other exciting developments in areas like the embedded space and the "internet of things" (M2M), robotics, optimization, and the cloud (among others), but I think you get the idea. JavaOne == brainExpansion;  Hope to see you there next year!

  Read the article

• On Reflector Pricing

  - by Nick Harrison

  I have heard a lot of outrage over Red Gate's decision to charge for Reflector. In the interest of full disclosure, I am a fan of Red Gate. I have worked with them on several usability tests. They also sponsor Simple Talk where I publish articles. They are a good company. I am also a BIG fan of Reflector. I have used it since Lutz originally released it. I have written my own add-ins. I have written code to host reflector and use its object model in my own code. Reflector is a beautiful tool. The care that Lutz took to incorporate extensibility is amazing. I have never had difficulty convincing my fellow developers that it is a wonderful tool. Almost always, once anyone sees it in action, it becomes their favorite tool. This wide spread adoption and usability has made it an icon and pivotal pillar in the DotNet community. Even folks with the attitude that if it did not come out of Redmond then it must not be any good, still love it. It is ironic to hear everyone clamoring for it to be released as open source. Reflector was never open source, it was free, but you never were able to peruse the source code and contribute your own changes. You could not even use Reflector to view the source code. From the very beginning, it was never anyone's intention for just anyone to examine the source code and make their own contributions aside from the add-in model. Lutz chose to hand over the reins to Red Gate because he believed that they would be able to build on his original vision and keep the product viable and effective. He did not choose to make it open source, hoping that the community would be up to the challenge. The simplicity and elegance may well have been lost with the "design by committee" nature of open source. Despite being a wonderful and beloved tool, Reflector cannot be an easy tool to maintain. Maybe because it is so wonderful and beloved, it is even more difficult to maintain. At any rate, we have high expectations. Reflector must continue to be able to reasonably disassemble every language construct that the framework and core languages dream up. We want it to be fast, and we also want it to continue to be simple to use. No small order. Red Gate tried to keep the core product free. Sadly there was not enough interest in the Pro version to subsidize the rest of the expenses. $35 is a reasonable cost, more than reasonable. I have read the blog posts and forum posts complaining about the time associated with getting the expense approved. I have heard people complain about the cost being unreasonable if you are a developer from certain countries. Let's do the math. How much of a productivity boost is Reflector? How many hours do you think it saves you in a typical project? The next question is a little easier if you are a contractor or a consultant, but what is your hourly rate? If you are not a contractor, you can probably figure out an hourly rate. How long does it take to get a return on your investment? The value added proposition is not a difficult one to make. I have read people clamoring that Red Gate sucks and is evil. They complain about broken promises and conflicts of interest. Relax! Red Gate is not evil. The world is not coming to an end. The sun will come up tomorrow. I am sure that Red Gate will come up with options for volume licensing or site licensing for companies that want to get a licensed copy for their entire team. Don't panic, and I am sure that many great improvements are on the horizon. Switching the UI to WPF and including a tabbed interface opens up lots of possibilities.

  Read the article

• Add Widget via Action in Toolbar

  - by Geertjan

  The question of the day comes from Vadim, who asks on the NetBeans Platform mailing list: "Looking for example showing how to add Widget to Scene, e.g. by toolbar button click." Well, the solution is very similar to this blog entry, where you see a solution provided by Jesse Glick for VisiTrend in Boston: https://blogs.oracle.com/geertjan/entry/zoom_capability Other relevant articles to read are as follows: http://netbeans.dzone.com/news/which-netbeans-platform-action http://netbeans.dzone.com/how-to-make-context-sensitive-actions Let's go through it step by step, with this result in the end, a solution involving 4 classes split (optionally, since a central feature of the NetBeans Platform is modularity) across multiple modules: The Customer object has a "name" String and the Droppable capability has a method "doDrop" which takes a Customer object: public interface Droppable {    void doDrop(Customer c);} In the TopComponent, we use "TopComponent.associateLookup" to publish an instance of "Droppable", which creates a new LabelWidget and adds it to the Scene in the TopComponent. Here's the TopComponent constructor: public CustomerCanvasTopComponent() {    initComponents();    setName(Bundle.CTL_CustomerCanvasTopComponent());    setToolTipText(Bundle.HINT_CustomerCanvasTopComponent());    final Scene scene = new Scene();    final LayerWidget layerWidget = new LayerWidget(scene);    Droppable d = new Droppable(){        @Override        public void doDrop(Customer c) {            LabelWidget customerWidget = new LabelWidget(scene, c.getTitle());            customerWidget.getActions().addAction(ActionFactory.createMoveAction());            layerWidget.addChild(customerWidget);            scene.validate();        }    };    scene.addChild(layerWidget);    jScrollPane1.setViewportView(scene.createView());    associateLookup(Lookups.singleton(d));} The Action is displayed in the toolbar and is enabled only if a Droppable is currently in the Lookup: @ActionID(        category = "Tools",        id = "org.customer.controler.AddCustomerAction")@ActionRegistration(        iconBase = "org/customer/controler/icon.png",        displayName = "#AddCustomerAction")@ActionReferences({    @ActionReference(path = "Toolbars/File", position = 300)})@NbBundle.Messages("AddCustomerAction=Add Customer")public final class AddCustomerAction implements ActionListener {    private final Droppable context;    public AddCustomerAction(Droppable droppable) {        this.context = droppable;    }    @Override    public void actionPerformed(ActionEvent ev) {        NotifyDescriptor.InputLine inputLine = new NotifyDescriptor.InputLine("Name:", "Data Entry");        Object result = DialogDisplayer.getDefault().notify(inputLine);        if (result == NotifyDescriptor.OK_OPTION) {            Customer customer = new Customer(inputLine.getInputText());            context.doDrop(customer);        }    }} Therefore, when the Properties window, for example, is selected, the Action will be disabled. (See the Zoomable example referred to in the link above for another example of this.) As you can see above, when the Action is invoked, a Droppable must be available (otherwise the Action would not have been enabled). The Droppable is obtained in the Action and a new Customer object is passed to its "doDrop" method. The above in pictures, take note of the enablement of the toolbar button with the red dot, on the extreme left of the toolbar in the screenshots below: The above shows the JButton is only enabled if the relevant TopComponent is active and, when the Action is invoked, the user can enter a name, after which a new LabelWidget is created in the Scene. The source code of the above is here: http://java.net/projects/nb-api-samples/sources/api-samples/show/versions/7.3/misc/WidgetCreationFromAction Note: Showing this as an MVC example is slightly misleading because, depending on which model object ("Customer" and "Droppable") you're looking at, the V and the C are different. From the point of view of "Customer", the TopComponent is the View, while the Action is the Controler, since it determines when the M is displayed. However, from the point of view of "Droppable", the TopComponent is the Controler, since it determines when the Action, i.e., which is in this case the View, displays the presence of the M.

  Read the article

• My Feelings About Microsoft Surface

  - by Valter Minute

  Advice: read the title carefully, I’m talking about “feelings” and not about advanced technical points proved in a scientific and objective way I still haven’t had a chance to play with a MS Surface tablet (I would love to, of course) and so my ideas just came from reading different articles on the net and MS official statements. Remember also that the MVP motto begins with “Independent” (“Independent Experts. Real World Answers.”) and this is just my humble opinion about a product and a technology. I know that, being an MS MVP you can be called an “MS-fanboy”, I don’t care, I hope that people can appreciate my opinion, even if it doesn’t match theirs. The “Surface” brand can be confusing for techies that knew the “original” surface concept but I think that will be a fresh new brand name for most of the people out there. But marketing department are here to confuse people… so I can understand this “recycle” of an existing name. So Microsoft is entering the hardware arena… for me this is good news. Microsoft developed some nice hardware in the past: the xbox, zune (even if the commercial success was quite limited) and, last but not least, the two arc mices (old and new model) that I use and appreciate. In the past Microsoft worked with OEMs and that model lead to good and bad things. Good thing (for microsoft, at least) is market domination by windows-based PCs that only in the last years has been reduced by the return of the Mac and tablets. Google is also moving in the hardware business with its acquisition of Motorola, and Apple leveraged his control of both the hardware and software sides to develop innovative products. Microsoft can scare OEMs and make them fly away from windows (but where?) or just lead the pack, showing how devices should be designed to compete in the market and bring back some of the innovation that disappeared from recent PC products (look at the shelves of your favorite electronics store and try to distinguish a laptop between the huge mass of anonymous PCs on displays… only Macs shine out there…). Having to compete with MS “official” hardware will force OEMs to develop better product and bring back some real competition in a market that was ruled only by prices (the lower the better even when that means low quality) and no innovative features at all (when it was the last time that a new PC surprised you?). Moving into a new market is a big and risky move, but with Windows 8 Microsoft is playing a crucial move for its future, trying to be back in the innovation run against apple and google. MS can’t afford to fail this time. I saw the new devices (the WinRT and Pro) and the specifications are scarce, misleading and confusing. The first impression is that the device looks like an iPad with a nice keyboard cover… Using “HD” and “full HD” to define display resolution instead of using the real figures and reviving the “ClearType” brand (now dead on Win8 as reported here and missed by people who hate to read text on displays, like myself) without providing clear figures (couldn’t you count those damned pixels?) seems to imply that MS was caught by surprise by apple recent “retina” displays that brought very high definition screens on tablets.Also there are no specifications about the processors used (even if some sources report NVidia Tegra for the ARM tablet and i5 for the x86 one) and expected battery life (a critical point for tablets and the point that killed Windows7 x86 based tablets). Also nothing about the price, and this will be another critical point because other platform out there already provide lots of applications and have a good user base, if MS want to enter this market tablets pricing must be competitive. There are some expansion ports (SD and USB), so no fixed storage model (even if the specs talks about 32-64GB for RT and 128-256GB for pro). I like this and don’t like the apple model where flash memory (that it’s dirt cheap used in thumdrives or SD cards) is as expensive as gold (or cocaine to have a more accurate per gram measurement) when mounted inside a tablet/phone. For big files you’ll be able to use external media and an SD card could be used to store files that don’t require super-fast SSD-like access times, I hope. To be honest I really don’t like the marketplace model and the limitation of Windows RT APIs (no local database? from a company that based a good share of its success on VB6+Access!) and lack of desktop support on the ARM (even if the support is here and has been used to port office). It’s a step toward the consumer market (where competitors are making big money), but may impact enterprise (and embedded) users that may not appreciate Windows 8 new UI or the limitations of the new app model (if you aren’t connected you are dead ). Not having compatibility with the desktop will require brand new applications and honestly made all the CPU cycles spent to convert .NET IL into real machine code in the past like a huge waste of time… as soon as a new processor architecture is supported by Windows you still have to rewrite part of your application (and MS is pushing HTML5+JS and native code more than .NET in my perception). On the other side I believe that the development experience provided by Visual Studio is still miles (or kilometres) ahead of the competition and even the all-uppercase menu of VS2012 hasn’t changed this situation. The new metro UI got mixed reviews. On my side I should say that is very pleasant to use on a touch screen, I like the minimalist design (even if sometimes is too minimal and hides stuff that, in my opinion, should be visible) but I should also say that using it with mouse and keyboard is like trying to pick your nose with boxing gloves… Metro is also very interesting for embedded devices where touch screen usage is quite common and where having an application taking all the screen is the norm. For devices like kiosks, vending machines etc. this kind of UI can be a great selling point. I don’t need a new tablet (to be honest I’m pretty happy with my wife’s iPad and with my PC), but I may change my opinion after having a chance to play a little bit with those new devices and understand what’s hidden under all this mysterious and generic announcements and specifications!

  Read the article

• Rules for Naming

  - by PointsToShare

  © 2011 By: Dov Trietsch. All rights reserved Naming Documents (or is it “Document, Naming”?) Tis but thy name that is my enemy; Thou art thyself, though not a Montague. What's Montague? It is nor hand, nor foot, Nor arm, nor face, nor any other part Belonging to a man. O, be some other name! What's in a name? That which we call a rose By any other name would smell as sweet; So Romeo would, were he not Romeo call'd, Retain that dear perfection which he owes Without that title. Romeo, doff thy name And for that name which is no part of thee Take all myself.  Shakespeare – Romeo and Juliet Act II, Scene 2 We normally only use the bold portion of the famous Shakespearean quote above, but it is really out of context. As the play unfolds, we learn that a name is all too powerful. Indeed it is because of their names that the doomed lovers die. There might be life and death in a name (BTW, when I wrote this monogram, I was in Hatfield, PA. Remember the Hatfields and the McCoys?) This is a bit extreme, but in the field of Knowledge Management (KM) names are of the utmost importance as well. When I write an article about managing SharePoint sites, how should I name it? “Managing a site” or “Site, managing”? Nine times out of ten I’d opt for the latter. Almost everything we do is “Managing” so to make life easier for a person looking for meaningful content, we title our articles starting with the differentiator rather than the common factor. As a rule of thumb, we start the name with the noun rather than the verb. It is not what we do that is the primary key; it is what we do it to. So, answer this – is it a “rule of thumb” or a “thumb rule?” This is tough. A lot of what we do when naming is a judgment call. Both thumb and rule are nouns, albeit concrete and abstract (more about this later), but to most people “thumb rule” is meaningless while “rule of thumb” is an idiom. The difference between knowledge and information is that knowledge is meaningful information placed in context. Thus I elect the “rule of thumb”. It is the more meaningful title. Abstract and Concrete are relative terms. Many nouns (and verbs) that are abstract to a commoner, are concrete to a practitioner of one profession or another and may even have different concrete meanings in different professional jargons. Think about “running”. To an executive it means running a business, to a marathoner its meaning is much more literal. Generally speaking, we store and disseminate knowledge within a practice more than we do it in general. Even dictionaries encyclopedias define terms as they apply to different audiences. The rule of thumb is to put the more concrete first, but within the audience’s jargon. Even the title of this monogram is a question. Do I name it “Naming Documents” or “Documents, Naming”? Well, my own rule of thumb (“Here he goes again!?”) states that the latter is better because it starts with a noun, but this is a document about naming more than it about documents. The rules of naming also apply to graphs and charts, excel spreadsheets, and so on. Thus, I vote for the former.  A better title could have been “Naming Objects” only the word “Object” is a bit too abstract. How about just “Naming” or “Naming, rules of”? You get the drift. One of the ways to resolve all of this is to store the documents in Knowledge-Bases, which may become the subjects of a future punditry. Knowledge bases use keywords to describe their content.  Use a Metadata store for the keywords to at least attempt some common grounds. Here is another general rule (rule of thumb?!!) – put at least the one keyword in the title. Use subtitles. Here is an example: Migrating documents – Screening, cleaning, and organizing our knowledge. The main keyword is “documents”, next is “migrating”, other keywords also appear in the subtitle. They are “screening”, “cleaning”, and “organizing”. Any questions? Send me an amply named document by email: [email protected]

  Read the article

• Are IE9 really good ?

  - by anirudha

  IE9 started a campaign for kill IE6 from the core because they know that IE6 is a big trouble or  problem for them for promote 9 version of IE. so they started a campaign for killing IE6. next time they kill IE 7 , 8,9 whenever they found this old version have a big problem for them to promote next version of IE.   Why they not make a update system who automatically update the browser and tell user to restart and update goes installed in the user system. well IE9 should learn from all other that they have very well design auto-update system who never give user in trouble that your browser goes old. Chrome and Firefox both update themselves and say user restart to enjoy another good version. in IE6 a big problem is that updates. no one sure that they installed new version of IE6 without any hassles and update goes install without any problem because they really know or care about “you need this to install this and this for this” so they thing “why I update IE whenever I am unsure that my browser goes update and I have no problem again” so they do nothing because their work done with no problem because common person used high profile application who work even in IE6. so they do nothing.    IE6 countdown website have designed a banner for warn or force user to upgrade to next version of IE. well there is no good reason for put the banner on website some of reason are:-   Windows 7 comes with pre-installed IE8 and Vista comes with upgrade version them IE6 so that is sure that you force a user who have Windows XP [luna] and if they want to upgrade IE then they can get IE8 not version 9 because IE9 is design for Windows 7 or Vista Service pack 2. so What is the use of update when user still have a outdate version too because IE8 is old version and not have any capability of HTML5 so forcing user by using the banner have no sense. I am not know why they all listed on website put the banner on their own website. it’s good that you offer user what they want instead of giving them a outdate version of IE again. My means to give a user list of browser they can try to enhance their browser experience instead of only IE.   IE9 build upon WPF and they spent more time on using WPF in IE instead of making user experience browser.  many thing is designed wrongly in IE first thing is tabs. the tabs in chrome are bigger and easily to move and same in Firefox even not have smooth tabbing. IE have same tabbing as chrome have but leak a point that it’s too small. if you really  want to move then sometime they create a problem that they going elsewhere from the current instance of IE.   Chrome have a big buttons, tabs and menu to enhance browser experience and Firefox have a good feature that you can make them bigger or small. you can put the icon for add-ons on the toolbar for easily use but IE have no relation with customization so we never can thinking about that.   When chrome provide lot’s of extensions and a  webstore for browser application and same feature in Firefox can be seen then there is no plugin in IE. really you can see their IE addons Website where no plugin listed for web development. even in the category or tag. as a response from many blog there is new for developer that new version of IE9 developer tool. well IE9 have three new tabs a blogger tell on their blog. when I trying them I found many thing but I still unable to edit the Css from the HTML tab and no plugin I found I can get to enhance IE9 web development. something more other provide never IE9 give me like personas , customization , browser extension or any other they used to tell a small thing customization  .   IE9 still have some problem with JavaScript that when I use Firefox and chrome and logout in both then my cookie is deleted but in IE it’s not done. it’s show me that IE9 still have different from other not for good thing even some bad thing too. When I trying to read a article that is written in Hindi using Unicode font I found that they show many thing misspelled. there is three Sha in Hindi but they all goes wrong in IE. the misprint thing is not that the writing  for the articles goes wrong. it’s problem or browser to rendering a font. the Firefox and chrome not give me this problem even opera render the font in italic style by decrease the font-size but all those work perfect.   in Pwn2Own the apple’s safari  and IE9 both are hacked. this is a awesome news for whose who thing that  open-source is lose in  Security and close-source is highly-secured software. well this is not a good parameter for talking about software. it’s should depend how much application tested and used. because more testing and more use of application make them better.   I  appreciate IE to making their new version 9 and good luck for them. there is a another matter that I personally found nothing on them.

  Read the article

• How to fix Ubuntu 12.04.3 boot to black screen full of errors in white text, after upgrading on dell inspiron 1501

  - by Ibuntu

  I am running a Dell Inspiron 1501 I use Linux only. No Microsoft or Apple operating systems (or really anything closed-source). I've only been using Linux for a little over a year but I'm starting to gain a comfortable level of familiarity with the system and terminology. I've been having some issues with Quantel Quetzal and Raring Ringtail, especially with older hardware, so I opted to install Ubuntu 12.04.3 Precise Pangolin on the Inspiron 1501. I checked my MD5 sum after downloading my ISO and all was good. I have in fact used this iso/dvd to install Precise Pangolin successfully on a few other systems (some of which are even older than this laptop). Install goes fine. The wireless card doesn't work out of the box but this is a known issue which is fairly easy to fix. So, first thing I did was open up a terminal and run sudo apt-get update && sudo apt-get upgrade which, part way through, crashed (I assume lightdm and possibly X) and took me to a black screen filled with white lines of text that were either errors or just the ouputs of commands. The reason I say that is because I was unable to gleam any useful information from the output on the screen. I did take a picture however and will post a link. After that, every time I boot the system it goes right to that black screen posting all the error messages or output in white text. I never get a purple Ubuntu splash, so from what I can tell after reading this wiki article: https://wiki.ubuntu.com/X/Troubleshooting/BlankScreen That means that after the kernel is selected, it is unable to correctly implement the settings it needs. If the purple splash never shows, the frame buffer was never set correctly right? This leads me to believe that it could be a kernel issue? The wiki suggested to try and pinpoint the issue by rolling back kernels until I find one that works. Is this my best option? I think I'm going to give it a try anyways and will let everyone know if I am able to solve the issue this way. I have since done a few reinstalls and some trouble-shooting including a couple hours scouring the net for anyone with any kind of similar issue. Most of the issues I could find involved getting a black screen after login and none of them said anything about any information output on this black screen. My reinstalls have taught me that there is no issue updating, but as soon as I run sudo apt-get upgrade my system goes to the black screen and every time I boot it up it does the same thing. The only way to fix is by reinstall. I never get any ability to log in. After a hard power off to the laptop (because I cannot use ctrl+alt+del to reboot) when it boots again it goes to the grub boot menu and I can select between regular boot, recovery mode and the two memtest options. I never tried the memtest options but the other two both lead to the same black screen. Some people having a black/blank screen issue claim to have fixed it by using 12.10 or 13.04 but I believe they were having a different issue where they got a black/blank screen after logging in. I think I will still give these images a try, but mostly figured I would just wait another day or two for 13.10. Other things I figured I would try from the following three articles: After logging in, there's a black screen and my cursor, nothing else! in Ubuntu 12.10 Black Screen on Login After Upgrading to 12.04 I can't get to the login screen include opening a terminal using ctrl+alt+f1 and trying a variety of reseting unity, x settings, lightdm (or switching to gdm); but I doubt this will work or that I will even be able to access a terminal. I'm pretty sure the whole system is stuck after it loads the last line on the black screen. I will try these things and post more information when I have. Hopefully someone has an idea in the meantime and I will keep checking back trying to find a solution. Thank you. Here are 3 different pictures of the error message. I had to take with my phone: http://ubuntuone.com/album/0TBBkxmVajJIQQtoN9mVdN

  Read the article

• Deduping your redundancies

  - by nospam(at)example.com (Joerg Moellenkamp)

  Robin Harris of Storagemojo pointed to an interesting article about about deduplication and it's impact to the resiliency of your data against data corruption on ACM Queue. The problem in short: A considerable number of filesystems store important metadata at multiple locations. For example the ZFS rootblock is copied to three locations. Other filesystems have similar provisions to protect their metadata. However you can easily proof, that the rootblock pointer in the uberblock of ZFS for example is pointing to blocks with absolutely equal content in all three locatition (with zdb -uu and zdb -r). It has to be that way, because they are protected by the same checksum. A number of devices offer block level dedup, either as an option or as part of their inner workings. However when you store three identical blocks on them and the devices does block level dedup internally, the device may just deduplicated your redundant metadata to a block stored just once that is stored on the non-voilatile storage. When this block is corrupted, you have essentially three corrupted copies. Three hit with one bullet. This is indeed an interesting problem: A device doing deduplication doesn't know if a block is important or just a datablock. This is the reason why I like deduplication like it's done in ZFS. It's an integrated part and so important parts don't get deduplicated away. A disk accessed by a block level interface doesn't know anything about the importance of a block. A metadata block is nothing different to it's inner mechanism than a normal data block because there is no way to tell that this is important and that those redundancies aren't allowed to fall prey to some clever deduplication mechanism. Robin talks about this in regard of the Sandforce disk controllers who use a kind of dedup to reduce some of the nasty effects of writing data to flash, but the problem is much broader. However this is relevant whenever you are using a device with block level deduplication. It's just the point that you have to activate it for most implementation by command, whereas certain devices do this by default or by design and you don't know about it. However I'm not perfectly sure about that ? given that storage administration and server administration are often different groups with different business objectives I would ask your storage guys if they have activated dedup without telling somebody elase on their boxes in order to speak less often with the storage sales rep. The problem is even more interesting with ZFS. You may use ditto blocks to protect important data to store multiple copies of data in the pool to increase redundancy, even when your pool just consists out of one disk or just a striped set of disk. However when your device is doing dedup internally it may remove your redundancy before it hits the nonvolatile storage. You've won nothing. Just spend your disk quota on the the LUNs in the SAN and you make your disk admin happy because of the good dedup ratio However you can just fall in this specific "deduped ditto block"trap when your pool just consists out of a single device, because ZFS writes ditto blocks on different disks, when there is more than just one disk. Yet another reason why you should spend some extra-thought when putting your zpool on a single LUN, especially when the LUN is sliced and dices out of a large heap of storage devices by a storage controller. However I have one problem with the articles and their specific mention of ZFS: You can just hit by this problem when you are using the deduplicating device for the pool. However in the specifically mentioned case of SSD this isn't the usecase. Most implementations of SSD in conjunction with ZFS are hybrid storage pools and so rotating rust disk is used as pool and SSD are used as L2ARC/sZIL. And there it simply doesn't matter: When you really have to resort to the sZIL (your system went down, it doesn't matter of one block or several blocks are corrupt, you have to fail back to the last known good transaction group the device. On the other side, when a block in L2ARC is corrupt, you simply read it from the pool and in HSP implementations this is the already mentioned rust. In conjunction with ZFS this is more interesting when using a storage array, that is capable to do dedup and where you use LUNs for your pool. However as mentioned before, on those devices it's a user made decision to do so, and so it's less probable that you deduplicating your redundancies. Other filesystems lacking acapability similar to hybrid storage pools are more "haunted" by this problem of SSD using dedup-like mechanisms internally, because those filesystem really store the data on the the SSD instead of using it just as accelerating devices. However at the end Robin is correct: It's jet another point why protecting your data by creating redundancies by dispersing it several disks (by mirror or parity RAIDs) is really important. No dedup mechanism inside a device can dedup away your redundancy when you write it to a totally different and indepenent device.

  Read the article

• Local LINQtoSQL Database For Your Windows Phone 7 Application

  - by Tim Murphy

  There aren’t many applications that are of value without having some for of data store.  In Windows Phone development we have a few options.  You can store text directly to isolated storage.  You can also use a number of third party libraries to create or mimic databases in isolated storage.  With Mango we gained the ability to have a native .NET database approach which uses LINQ to SQL.  In this article I will try to bring together the components needed to implement this last type of data store and fill in some of the blanks that I think other articles have left out. Defining A Database The first things you are going to need to do is define classes that represent your tables and a data context class that is used as the overall database definition.  The table class consists of column definitions as you would expect.  They can have relationships and constraints as with any relational DBMS.  Below is an example of a table definition. First you will need to add some assembly references to the code file. using System.ComponentModel;using System.Data.Linq;using System.Data.Linq.Mapping; You can then add the table class and its associated columns.  It needs to implement INotifyPropertyChanged and INotifyPropertyChanging.  Each level of the class needs to be decorated with the attribute appropriate for that part of the definition.  Where the class represents the table the properties represent the columns.  In this example you will see that the column is marked as a primary key and not nullable with a an auto generated value. You will also notice that the in the column property’s set method It uses the NotifyPropertyChanging and NotifyPropertyChanged methods in order to make sure that the proper events are fired. [Table]public class MyTable: INotifyPropertyChanged, INotifyPropertyChanging{ public event PropertyChangedEventHandler PropertyChanged; private void NotifyPropertyChanged(string propertyName) { if(PropertyChanged != null) { PropertyChanged(this, new PropertyChangedEventArgs(propertyName)); } } public event PropertyChangingEventHandler PropertyChanging; private void NotifyPropertyChanging(string propertyName) { if(PropertyChanging != null) { PropertyChanging(this, new PropertyChangingEventArgs(propertyName)); } } private int _TableKey; [Column(IsPrimaryKey = true, IsDbGenerated = true, DbType = "INT NOT NULL Identity", CanBeNull = false, AutoSync = AutoSync.OnInsert)] public int TableKey { get { return _TableKey; } set { NotifyPropertyChanging("TableKey"); _TableKey = value; NotifyPropertyChanged("TableKey"); } } The last part of the database definition that needs to be created is the data context.  This is a simple class that takes an isolated storage location connection string its constructor and then instantiates tables as public properties. public class MyDataContext: DataContext{ public MyDataContext(string connectionString): base(connectionString) { MyRecords = this.GetTable<MyTable>(); } public Table<MyTable> MyRecords;} Creating A New Database Instance Now that we have a database definition it is time to create an instance of the data context within our Windows Phone app.  When your app fires up it should check if the database already exists and create an instance if it does not.  I would suggest that this be part of the constructor of your ViewModel. db = new MyDataContext(connectionString);if(!db.DatabaseExists()){ db.CreateDatabase();} The next thing you have to know is how the connection string for isolated storage should be constructed.  The main sticking point I have found is that the database cannot be created unless the file mode is read/write.  You may have different connection strings but the initial one needs to be similar to the following. string connString = "Data Source = 'isostore:/MyApp.sdf'; File Mode = read write"; Using you database Now that you have done all the up front work it is time to put the database to use.  To make your life a little easier and keep proper separation between your view and your viewmodel you should add a couple of methods to the viewmodel.  These will do the CRUD work of your application.  What you will notice is that the SubmitChanges method is the secret sauce in all of the methods that change data. private myDataContext myDb;private ObservableCollection<MyTable> _viewRecords;public ObservableCollection<MyTable> ViewRecords{ get { return _viewRecords; } set { _viewRecords = value; NotifyPropertyChanged("ViewRecords"); }}public void LoadMedstarDbData(){ var tempItems = from MyTable myRecord in myDb.LocalScans select myRecord; ViewRecords = new ObservableCollection<MyTable>(tempItems);}public void SaveChangesToDb(){ myDb.SubmitChanges();}public void AddMyTableItem(MyTable newScan){ myDb.LocalScans.InsertOnSubmit(newScan); myDb.SubmitChanges();}public void DeleteMyTableItem(MyTable newScan){ myDb.LocalScans.DeleteOnSubmit(newScan); myDb.SubmitChanges();} Updating existing database What happens when you need to change the structure of your database?  Unfortunately you have to add code to your application that checks the version of the database which over time will create some pollution in your codes base.  On the other hand it does give you control of the update.  In this example you will see the DatabaseSchemaUpdater in action.  Assuming we added a “Notes” field to the MyTable structure, the following code will check if the database is the latest version and add the field if it isn’t. if(!myDb.DatabaseExists()){ myDb.CreateDatabase();}else{ DatabaseSchemaUpdater dbUdater = myDb.CreateDatabaseSchemaUpdater(); if(dbUdater.DatabaseSchemaVersion < 2) { dbUdater.AddColumn<MyTable>("Notes"); dbUdater.DatabaseSchemaVersion = 2; dbUdater.Execute(); }} Summary This approach does take a fairly large amount of work, but I think the end product is robust and very native for .NET developers.  It turns out to be worth the investment. del.icio.us Tags: Windows Phone,Windows Phone 7,LINQ to SQL,LINQ,Database,Isolated Storage

  Read the article

• StreamInsight 2.1 Released

  - by Roman Schindlauer

  The wait is over—we are pleased to announce the release of StreamInsight 2.1. Since the release of version 1.2, we have heard your feedbacks and suggestions and based on that we have come up with a whole new set of features. Here are some of the highlights: A New Programming Model – A more clear and consistent object model, eliminating the need for complex input and output adapters (though they are still completely supported). This new model allows you to provision, name, and manage data sources and sinks in the StreamInsight server. Tight integration with Reactive Framework (Rx) – You can write reactive queries hosted inside StreamInsight as well as compose temporal queries on reactive objects. High Availability – Check-pointing over temporal streams and multiple processes with shared computation. Here is how simple coding can be with the 2.1 Programming Model: class Program {     static void Main(string[] args)     {         using (Server server = Server.Create("Default"))         {             // Create an app             Application app = server.CreateApplication("app");             // Define a simple observable which generates an integer every second             var source = app.DefineObservable(() =>                 Observable.Interval(TimeSpan.FromSeconds(1)));             // Define a sink.             var sink = app.DefineObserver(() =>                 Observer.Create<long>(x => Console.WriteLine(x)));             // Define a query to filter the events             var query = from e in source                         where e % 2 == 0                         select e;             // Bind the query to the sink and create a runnable process             using (IDisposable proc = query.Bind(sink).Run("MyProcess"))             {                 Console.WriteLine("Press a key to dispose the process...");                 Console.ReadKey();             }         }     } }   That’s how easily you can define a source, sink and compose a query and run it. Note that we did not replace the existing APIs, they co-exist with the new surface. Stay tuned, you will see a series of articles coming out over the next few weeks about the new features and how to use them. Come and grab it from our download center page and let us know what you think! You can find the updated MSDN documentation here, and we would appreciate if you could provide feedback to the docs as well—best via email to [email protected]. Moreover, we updated our samples to demonstrate the new programming surface. Regards, The StreamInsight Team

  Read the article

• StreamInsight 2.1 Released

  - by Roman Schindlauer

  The wait is over—we are pleased to announce the release of StreamInsight 2.1. Since the release of version 1.2, we have heard your feedbacks and suggestions and based on that we have come up with a whole new set of features. Here are some of the highlights: A New Programming Model – A more clear and consistent object model, eliminating the need for complex input and output adapters (though they are still completely supported). This new model allows you to provision, name, and manage data sources and sinks in the StreamInsight server. Tight integration with Reactive Framework (Rx) – You can write reactive queries hosted inside StreamInsight as well as compose temporal queries on reactive objects. High Availability – Check-pointing over temporal streams and multiple processes with shared computation. Here is how simple coding can be with the 2.1 Programming Model: class Program {     static void Main(string[] args)     {         using (Server server = Server.Create("Default"))         {             // Create an app             Application app = server.CreateApplication("app");             // Define a simple observable which generates an integer every second             var source = app.DefineObservable(() =>                 Observable.Interval(TimeSpan.FromSeconds(1)));             // Define a sink.             var sink = app.DefineObserver(() =>                 Observer.Create<long>(x => Console.WriteLine(x)));             // Define a query to filter the events             var query = from e in source                         where e % 2 == 0                         select e;             // Bind the query to the sink and create a runnable process             using (IDisposable proc = query.Bind(sink).Run("MyProcess"))             {                 Console.WriteLine("Press a key to dispose the process...");                 Console.ReadKey();             }         }     } }   That’s how easily you can define a source, sink and compose a query and run it. Note that we did not replace the existing APIs, they co-exist with the new surface. Stay tuned, you will see a series of articles coming out over the next few weeks about the new features and how to use them. Come and grab it from our download center page and let us know what you think! You can find the updated MSDN documentation here, and we would appreciate if you could provide feedback to the docs as well—best via email to [email protected]. Moreover, we updated our samples to demonstrate the new programming surface. Regards, The StreamInsight Team

  Read the article

• Run CGI in IIS 7 to work with GET without Requiring POST Request

  - by Mohamed Meligy

  I'm trying to migrate an old CGI application from an existing Windows 2003 server (IIS 6.0) where it works just fine to a new Windows 2008 server with IIS 7.0 where we're getting the following problem: After setting up the module handler and everything, I find that I can only access the CGI application (rdbweb.exe) file if I'm calling it via POST request (form submit from another page). If I just try to type in the URL of the file (issuing a GET request) I get the following error: HTTP Error 502.2 - Bad Gateway The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are "Exception EInOutError in module rdbweb.exe at 00039B44. I/O error 6. ". This is a very old application for one of our clients. When we tried to call the vendor they said we need to pay ~ $3000 annual support fee in order to start the talk about it. Of course I'm trying to avoid that! Note that: If we create a normal HTML form that submits to "rdbweb.exe", we get the CGI working normally. We can't use this as workaround though because some pages in the application link to "rdbweb.exe" with normal link not form submit. If we run "rdbweb.exe". from a Console (Command Prompt) Window not IIS, we get the normal HTML we'd typically expect, no problem. We have tried the following: Ensuring the CGI module mapped to "rdbweb.exe".in IIS has all permissions (read, write, execute) enabled and also all verbs are allowed not just specific ones, also tried allowing GET, POST explicitely. Ensuring the application bool has "enable 32 bit applications" set to true. Ensuring the website runs with an account that has full permissions on the "rdbweb.exe".file and whole website (although we know it "read", "execute" should be enough). Ensuring the machine wide IIS setting for "ISAPI and CGI Restrictions" has the full path to "rdbweb.exe".allowed. Making sure we have the latest Windows Updates (for IIS6 we found knowledge base articles stating bugs that require hot fixes for IIS6, but nothing similar was found for IIS7). Changing the module from CGI to Fast CGI, not working also Now the only remaining possibility we have instigated is the following Microsoft Knowledge Base article:http://support.microsoft.com/kb/145661 - Which is about: CGI Error: The specified CGI application misbehaved by not returning a complete set of HTTP headers. The headers it did return are: the article suggests the following solution: Modify the source code for the CGI application header output. The following is an example of a correct header: print "HTTP/1.0 200 OK\n"; print "Content-Type: text/html\n\n\n"; Unfortunately we do not have the source to try this out, and I'm not sure anyway whether this is the issue we're having. Can you help me with this problem? Is there a way to make the application work without requiring POST request? Note that on the old IIS6 server the application is working just fine, and I could not find any special IIS configuration that I may want to try its equivalent on IIS7.

  Read the article

• Kernel Mode Rootkit

  - by Pajarito

  On the other 3 computers in my family, I believe that we have a kernel-mode rootkit for windows. It appears that the same rootkit is on all of them. We think. We changed all the important passwords from my computer, running linux right now. On all of the infected computers is Symantic Endpoint Protection, because it's free from the university where my mom and dad work. In my opinion symantec is a piece of crap, seeing as it didn't even manager to delete the tracking cookies it found when I tried it on my own computer. The Computers and their set-ups: Computer A: Vista Business; symantec antivirus. runs it as admin, no password. IE8. no other security software other than what comes with windows. IE8 security settings the default Computer B: XP Home Premium; symantec antivirus. runs as normal user, no password, admin account with weak password, spybot, uses IE8 with default settings, sometimes Firefox Computer C: XP Home Premium; symantec antivirus. runs as normal user, no password, admin account with weak password, uses IE8 with default settings, no other security programs except what came with windows This is what's happening. Cut and pasted from my dad's forum post. -- When I scanned my laptop (Dell XPS M1330 with Windows Vista Small Business), Symantec Endpoint Protection hangs for a while, perhaps 10 seconds or so, on some of the following files 9129837.exe, hide_evr2.sys, VirusRemoval.vbs, NewVirusRemoval.vbs, dll.dll, alsmt.ext, and _epnt.sys. It does this if a run a scan that I set up to run on a new thumbnail drive and it does this even if the thumbnail is not plugged in. It doesn't seem to do this if I scan only the C: drive. I've check for problems with symantec endpoint protection and also with Microsoft Security Essentials and Malwarebytes Anti-Malware. They found nothing and I can't find anything by searching for hidden files. Next I tried microsoft's rootkitrevealer. It (rootkitrevealer) finds 279660 (or so) discrepancies and the interface is so glitchy after that I can't really figure out what is going on. The screen is squirrely. The rootkitrevealer pulls up many files in the folder \programdata\applicationdata and there are numberous appended \applicationdata on the end of that as well. -- As you can see, what we did was install MSE and MBAM and scan with both of them. Nothing but a tracking cookie. Then I took over and ran rootkitrevealer.exe from MicroSoft from a flash drive. It found a bunch of discrepancies, but only about 20 or so where security related, the rest being files that you just couldn't see from Windows Explorer. I couldn't see whether of not the files list above, the ones that the scan was hanging on, where in the list. The other thing is, I have no idea what to do about the things the scan comes up with. Then we checked the other computers and they do the same thing when you scan with Symantec. The people at the university seen to think that dad might not have a virus, but 2 of the computers slowed down noticably AND IE8 started acting all funny. None of my family is very computer oriented, and 2 of the possible causes for the rootkit are: -My dad bought a new flash drive, which shipped with a data security executable on it -My dad has to download lots of articles for his work Those are the only things that stand out, but it could have been anything. We are currently backing up our data, and I'll post again after trying IceSword 1.22. I just looked at my dad's forum topic, and someone recommended GMER. I'll try that too.

  Read the article

• How Hacker Can Access VPS CentOS 6 content?

  - by user2118559

  Just want to understand. Please, correct mistakes and write advices Hacker can access to VPS: 1. Through (using) console terminal, for example, using PuTTY. To access, hacker need to know port number, username and password. Port number hacker can know scanning open ports and try to login. The only way to login as I understand need to know username and password. To block (make more difficult) port scanning, need to use iptables configure /etc/sysconfig/iptables. I followed this https://www.digitalocean.com/community/articles/how-to-setup-a-basic-ip-tables-configuration-on-centos-6 tutorial and got *nat :PREROUTING ACCEPT [87:4524] :POSTROUTING ACCEPT [77:4713] :OUTPUT ACCEPT [77:4713] COMMIT *mangle :PREROUTING ACCEPT [2358:200388] :INPUT ACCEPT [2358:200388] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [2638:477779] :POSTROUTING ACCEPT [2638:477779] COMMIT *filter :INPUT DROP [1:40] :FORWARD ACCEPT [0:0] :OUTPUT ACCEPT [339:56132] -A INPUT -m state --state RELATED,ESTABLISHED -j ACCEPT -A INPUT -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG NONE -j DROP -A INPUT -p tcp -m tcp ! --tcp-flags FIN,SYN,RST,ACK SYN -m state --state NEW -j DROP -A INPUT -p tcp -m tcp --tcp-flags FIN,SYN,RST,PSH,ACK,URG FIN,SYN,RST,PSH,ACK,URG -j DROP -A INPUT -i lo -j ACCEPT -A INPUT -p tcp -m tcp --dport 80 -j ACCEPT -A INPUT -p tcp -m tcp --dport 110 -j ACCEPT -A INPUT -p tcp -m tcp --dport 22 -j ACCEPT -A INPUT -s 11.111.11.111/32 -p tcp -m tcp --dport 22 -j ACCEPT -A INPUT -p tcp -m tcp --dport 21 -j ACCEPT -A INPUT -s 11.111.11.111/32 -p tcp -m tcp --dport 21 -j ACCEPT COMMIT Regarding ports that need to be opened. If does not use ssl, then seems must leave open port 80 for website. Then for ssh (default 22) and for ftp (default 21). And set ip address, from which can connect. So if hacker uses other ip address, he can not access even knowing username and password? Regarding emails not sure. If I send email, using Gmail (Send mail as: (Use Gmail to send from your other email addresses)), then port 25 not necessary. For incoming emails at dynadot.com I use Email Forwarding. Does it mean that emails “does not arrive to VPS” (before arriving to VPS, emails are forwarded, for example to Gmail)? If emails does not arrive to VPS, then seems port 110 also not necessary. If use only ssl, must open port 443 and close port 80. Do not understand regarding port 3306 In PuTTY with /bin/netstat -lnp see Proto Recv-Q Send-Q Local Address Foreign Address State PID/Program name tcp 0 0 0.0.0.0:3306 0.0.0.0:* LISTEN 992/mysqld As understand it is for mysql. But does not remember that I have opened such port (may be when installed mysql, the port is opened automatically?). Mysql is installed on the same server, where all other content. Need to understand regarding port 3306 2. Also hacker may be able access console terminal through VPS hosting provider Control Panel (serial console emergency access). As understand only using console terminal (PuTTY, etc.) can make “global” changes (changes that can not modify with ftp). 3. Hacker can access to my VPS exploiting some hole in my php code and uploading, for example, Trojan. Unfortunately, faced situation that VPS was hacked. As understand it was because I used ZPanel. On VPS ( \etc\zpanel\panel\bin) ) found one php file, that was identified as Trojan by some virus scanners (at virustotal.com). Experimented with the file on local computer (wamp). And appears that hacker can see all content of VPS, rename, delete, upload etc. From my opinion, if in PuTTY use command like chattr +i /etc/php.ini then hacker could not be able to modify php.ini. Is there any other way to get into VPS?

  Read the article

• Amazon EC2 Instance - m1.medium Ubuntu 12.04 - Started to crash three days ago

  - by Joy

  The environment: Amazon EC2 Instance - m1.medium Ubuntu 12.04 Apache 2.2.22 - Running a Drupal Site Using MySQL DB Server RAM info: ~$ free -gt total used free shared buffers cached Mem: 3 1 2 0 0 0 -/+ buffers/cache: 0 2 Swap: 0 0 0 Total: 3 1 2 Hard drive info: Filesystem Size Used Avail Use% Mounted on /dev/xvda1 7.9G 4.7G 2.9G 62% / udev 1.9G 8.0K 1.9G 1% /dev tmpfs 751M 180K 750M 1% /run none 5.0M 0 5.0M 0% /run/lock none 1.9G 0 1.9G 0% /run/shm /dev/xvdb 394G 199M 374G 1% /mnt The problem About two days ago the site started failing becaue the MySQL server was shut down by Apache with the following message: kernel: [2963685.664359] [31716] 106 31716 226946 22748 0 0 0 mysqld kernel: [2963685.664730] Out of memory: Kill process 31716 (mysqld) score 23 or sacrifice child kernel: [2963685.664764] Killed process 31716 (mysqld) total-vm:907784kB, anon-rss:90992kB, file-rss:0kB kernel: [2963686.153608] init: mysql main process (31716) killed by KILL signal kernel: [2963686.169294] init: mysql main process ended, respawning That states that the VM was occupying 0.9GB, but my Ram has 2GB free, so 1GB was still left free. I understand that in Linux applications can allocate more memory than physically available. I don't know if this is the problme, it's the first time that it has started to happen. Obviously, the MySQL server tries to restart, but there's no memory for it apparently and it won't restart. Here is its error log: Plugin 'FEDERATED' is disabled. The InnoDB memory heap is disabled Mutexes and rw_locks use GCC atomic builtins Compressed tables use zlib 1.2.3.4 Initializing buffer pool, size = 128.0M InnoDB: mmap(137363456 bytes) failed; errno 12 Completed initialization of buffer pool Fatal error: cannot allocate memory for the buffer pool Plugin 'InnoDB' init function returned error. Plugin 'InnoDB' registration as a STORAGE ENGINE failed. Unknown/unsupported storage engine: InnoDB [ERROR] Aborting [Note] /usr/sbin/mysqld: Shutdown complete I simply restarted the Mysql service. About two hours later it happened again. I restarted it. Then it happened again 9 hours later. So then I thought of the MaxClients parameter of apache.conf, so I went to check it out. It was set at 150. I decided to drop it down to 60. As so: <IfModule mpm_prefork_module> ... MaxClients 60 </IfModule> <IfModule mpm_worker_module> ... MaxClients 60 </IfModule> <IfModule mpm_event_module> ... MaxClients 60 </IfModule> Once I did that, I had the apache2 service restart and it all went smoothly for 3/4 of a day. Since at night the MySQL service shut down once again, but this time it wasn't killed by the Apache2 service. Instead it called the OOM-Killer with the following message: kernel: [3104680.005312] mysqld invoked oom-killer: gfp_mask=0x201da, order=0, oom_adj=0, oom_score_adj=0 kernel: [3104680.005351] [<ffffffff81119795>] oom_kill_process+0x85/0xb0 kernel: [3104680.548860] init: mysql main process (30821) killed by KILL signal Now I'm out of ideas. Some articles state that the ideal thing to do is change the kernel behaviour with the following (include it to the file /etc/sysctl.conf ) vm.overcommit_memory = 2 vm.overcommit_ratio = 80 So no overcommits will take place. I'm wondering if this is the way to go? Keep in mind I'm no server administrator, I have basic knowldege. Thanks a bunch in advance.

  Read the article

• Disable Windows 8 edge gestures/hot corners for multi-touch applications while running in full screen

  - by Bondye

  I have a full screen AS3 game maby with Adobe AIR that runs in Windows 7. In this game it may not be easy to exit (think about kiosk mode, only exit by pressing esc and enter a password). Now I want this game to run in Windows 8. The game is working like expected but the anoying things are these edge gestures/hot corners (left, top, right, bottom) and the shortcuts. I've read articles but none helped me. People talk about registery edits, but I dont get this working + the user needs to restart his/hers computer. I want to open my game, turn off gestures/hot corners and when the game closes the gestures/hot corners need to come back available again. I have seen some applications doing the same what I want to accomplish. I found this so I am able to detect the gestures. But how to ignore they're actions? I also read ASUS Smart Gestures but this is for the touch-pad. And I have tried Classic Shell but I need to disable the edge gestures/hot corners without such programs, just on-the-fly. I also found this but I don't know how to implement this. HRESULT SetTouchDisableProperty(HWND hwnd, BOOL fDisableTouch) { IPropertyStore* pPropStore; HRESULT hrReturnValue = SHGetPropertyStoreForWindow(hwnd, IID_PPV_ARGS(&pPropStore)); if (SUCCEEDED(hrReturnValue)) { PROPVARIANT var; var.vt = VT_BOOL; var.boolVal = fDisableTouch ? VARIANT_TRUE : VARIANT_FALSE; hrReturnValue = pPropStore->SetValue(PKEY_EdgeGesture_DisableTouchWhenFullscreen, var); pPropStore->Release(); } return hrReturnValue; } Does anyone know how I can do this? Or point me into the right direction? I have tried some in C# and C++, but I aint a skilled C#/C++ developer. Also the game is made in AS3 so it will be hard to implement this in C#/C++. I work on the Lenovo aio (All in one) with Windows 8.

  Read the article

• Runge-Kutta (RK4) integration for game physics

  - by Kai

  Gaffer on Games has a great article about using RK4 integration for better game physics. The implementation is straightforward but the math behind it confuses me. I understand derivatives and integrals on a conceptual level but I haven't manipulated equations in a long time. Here's the brunt of Gaffer's implementation: void integrate(State &state, float t, float dt) { Derivative a = evaluate(state, t, 0.0f, Derivative()); Derivative b = evaluate(state, t+dt*0.5f, dt*0.5f, a); Derivative c = evaluate(state, t+dt*0.5f, dt*0.5f, b); Derivative d = evaluate(state, t+dt, dt, c); const float dxdt = 1.0f/6.0f * (a.dx + 2.0f*(b.dx + c.dx) + d.dx); const float dvdt = 1.0f/6.0f * (a.dv + 2.0f*(b.dv + c.dv) + d.dv) state.x = state.x + dxdt * dt; state.v = state.v + dvdt * dt; } Can anybody explain in simple terms how RK4 works? Specifically, why are we averaging the derivatives at 0.0f, 0.5f, 0.5f, and 1.0f? How is averaging derivatives up to the 4th order different from doing a simple euler integration with a smaller timestep? After reading the accepted answer below, and several other articles, I have a grasp on how RK4 works. To answer my own questions: Can anybody explain in simple terms how RK4 works? RK4 takes advantage of the fact that we can get a much better approximation of a function if we use its higher-order derivatives rather than just the first or second derivative. That's why the Taylor series converges much faster than Euler approximations. (take a look at the animation on the right side of that page) Specifically, why are we averaging the derivatives at 0.0f, 0.5f, 0.5f, and 1.0f? The Runge-Kutta method is an approximation of a function that samples derivatives of several points within a timestep, unlike the Taylor series which only samples derivatives of a single point. After sampling these derivatives we need to know how to weigh each sample to get the closest approximation possible. An easy way to do this is to pick constants that coincide with the Taylor series, which is how the constants of a Runge-Kutta equation are determined. This article made it clearer for me: http://web.mit.edu/10.001/Web/Course%5FNotes/Differential%5FEquations%5FNotes/node5.html. Notice how (15) is the Taylor series expansion while (17) is the Runge-Kutta derivation. How is averaging derivatives up to the 4th order different from doing a simple euler integration with a smaller timestep? Mathematically it converges much faster than doing many Euler approximations. Of course, with enough Euler approximations we can gain equal accuracy to RK4, but the computational power needed doesn't justify using Euler.

  Read the article

• ASP.NET GridView second header row to span main header row

  - by Dana Robinson

  I have an ASP.NET GridView which has columns that look like this: | Foo | Bar | Total1 | Total2 | Total3 | Is it possible to create a header on two rows that looks like this? | | Totals | | Foo | Bar | 1 | 2 | 3 | The data in each row will remain unchanged as this is just to pretty up the header and decrease the horizontal space that the grid takes up. The entire GridView is sortable in case that matters. I don't intend for the added "Totals" spanning column to have any sort functionality. Edit: Based on one of the articles given below, I created a class which inherits from GridView and adds the second header row in. namespace CustomControls { public class TwoHeadedGridView : GridView { protected Table InnerTable { get { if (this.HasControls()) { return (Table)this.Controls[0]; } return null; } } protected override void OnDataBound(EventArgs e) { base.OnDataBound(e); this.CreateSecondHeader(); } private void CreateSecondHeader() { GridViewRow row = new GridViewRow(0, -1, DataControlRowType.Header, DataControlRowState.Normal); TableCell left = new TableHeaderCell(); left.ColumnSpan = 3; row.Cells.Add(left); TableCell totals = new TableHeaderCell(); totals.ColumnSpan = this.Columns.Count - 3; totals.Text = "Totals"; row.Cells.Add(totals); this.InnerTable.Rows.AddAt(0, row); } } } In case you are new to ASP.NET like I am, I should also point out that you need to: 1) Register your class by adding a line like this to your web form: <%@ Register TagPrefix="foo" NameSpace="CustomControls" Assembly="__code"%> 2) Change asp:GridView in your previous markup to foo:TwoHeadedGridView. Don't forget the closing tag. Another edit: You can also do this without creating a custom class. Simply add an event handler for the DataBound event of your grid like this: protected void gvOrganisms_DataBound(object sender, EventArgs e) { GridView grid = sender as GridView; if (grid != null) { GridViewRow row = new GridViewRow(0, -1, DataControlRowType.Header, DataControlRowState.Normal); TableCell left = new TableHeaderCell(); left.ColumnSpan = 3; row.Cells.Add(left); TableCell totals = new TableHeaderCell(); totals.ColumnSpan = grid.Columns.Count - 3; totals.Text = "Totals"; row.Cells.Add(totals); Table t = grid.Controls[0] as Table; if (t != null) { t.Rows.AddAt(0, row); } } } The advantage of the custom control is that you can see the extra header row on the design view of your web form. The event handler method is a bit simpler, though.

  Read the article

• How to assess a job offer with stock options? [closed]

  - by seas

  Cannot help expressing my curiosity about this issue. First of all, Russia, a country, I live in, as far as I understand, is a virgin land on this matter. Motivation is purely developed here and options are not existed at all. So, I am absolutely not aware about this. I roughly understand the mechanism of options. And, as far as I understand, the major white spot in the whole that story, how much will a singe share cost. How much will I get from all those N x 1000 options? I see two ways one can get money from the business: 1. Business goes IPO !!! 2. Business is sold as a whole to another owner. Next way is rather questionable about getting money: 3. Business goes without IPO "forever" (a generation would rather die before it IPO). I am also interested some explanations about situation ?3. Situation ?1 is clear - market decides everything, you either wait for stock price you satisfied or sell everything now. But topic is rather about ?2 - business is sold to another business. I am considering the following model: I am well payed specialist with company X. Somebody, with a company Y makes me an offer. Y is a startup. They cannot offer me much money and cannot overbid my salary, but they grow fast and hope to be bought soon. Instead of money, they offer me N x 1000 options. My problem is "how to assess this offer against my current, stable and well-payed job"? Are there any average cost of virtual share during selling one company to another? Are there any average stock price companies prefer to go to IPO? Are there any barriers against spreading the value of sock before selling the company or IPO (hiring too much people with options package too fast will decrease each package value, I mean)? Are there any good articles with explanations? Is all that somehow written in the law?

  Read the article

• Single Sign On for a Web App

  - by Jeremy Goodell

  I have been trying to understand how this problem is solved for over a month now. I really need to come up with a general approach that works -- I'm basically the only resource who can do it. I have a theory, but I'm just not sure it's the easiest (or correct) approach and I haven't been able to find any information to support my ideas. Here's the scenario: 1) You have a complex web application that offers secure content on a subscription basis. 2) Users are required to log in to your application with user name and password. 3) You sell to large corporations, which already have a corporate authentication technology (for example, Active Directory). 4) You would like to integrate with the corporate authentication mechanism to allow their users to log onto your Web App without having to enter their user name and password. Now, any solution you come up with will have to provide a mechanism for: adding new users removing users changing user information allowing users to log in Ideally, all these would happen "automagically" when the corporate customer made the corresponding changes to their own authentication. Now, I have a theory that the way to do this (at least for Active Directory) would be for me to write a client-side app that integrates with the customer's Active Directory to track the targeted changes, and then communicate those changes to my Web App. I think that if this communication were done via Web Services offered by my web app, then it would maintain an unhackable level of security, which would obviously be a requirement for these corporate customers. I've found some information about a Microsoft product called Active Directory Federation Service (ADFS) which may or may not be the right approach for me. It seems to be a bit bulky and have some requirements that might not work for all customers. For other existing ID scenarios (like Athens and Shibboleth), I don't think a client application is necessary. It's probably just a matter of tying into the existing ID services. I would appreciate any advice anyone has on anything I've mentioned here. In particular, if you can tell me if my theory is correct about providing a client-side app that communicates with server-side Web Services, or if I'm totally going in the wrong direction. Also, if you could point me at any web sites or articles that explain how to do this, I'd really appreciate it. My research has not turned up much so far. Finally, if you could let me know of any Web applications that currently offer this service (particularly as tied to a corporate Active Directory), I would be very grateful. I am wondering if other B2B Web app's like salesforce.com, or hoovers.com offer a similar service for their corporate customers. I hate being in the dark and would greatly appreciate any light you can shed ... Jeremy

  Read the article

• availability of Win32_MountPoint and Win32_Volume on Windows XP?

  - by SteveC

  From the MSDN articles I've found -- http://msdn.microsoft.com/en-us/library/aa394515(v=VS.85).aspx -- Win32_Volume and Win32_MountPoint aren't available on Windows XP. However, I'm developing a C# app on Windows XP (64bit), and I can get to those WMI classes just fine. Users of my app will be on Windows XP sp2 with .Net 3.5 sp1. Googling around, I can't determine whether I can count on this or not. Am I successful on my system because of one or more of the following: - windows xp service pack 2? - visual studio 2008 sp1 was installed? - .Net 3.5 sp1? Should I use something other than WMI to get at the volume/mountpoint info? Below is sample code that's working... public static Dictionary<string, NameValueCollection> GetAllVolumeDeviceIDs() { Dictionary<string, NameValueCollection> ret = new Dictionary<string, NameValueCollection>(); // retrieve information from Win32_Volume try { using (ManagementClass volClass = new ManagementClass("Win32_Volume")) { using (ManagementObjectCollection mocVols = volClass.GetInstances()) { // iterate over every volume foreach (ManagementObject moVol in mocVols) { // get the volume's device ID (will be key into our dictionary) string devId = moVol.GetPropertyValue("DeviceID").ToString(); ret.Add(devId, new NameValueCollection()); //Console.WriteLine("Vol: {0}", devId); // for each non-null property on the Volume, add it to our NameValueCollection foreach (PropertyData p in moVol.Properties) { if (p.Value == null) continue; ret[devId].Add(p.Name, p.Value.ToString()); //Console.WriteLine("\t{0}: {1}", p.Name, p.Value); } // find the mountpoints of this volume using (ManagementObjectCollection mocMPs = moVol.GetRelationships("Win32_MountPoint")) { foreach (ManagementObject moMP in mocMPs) { // only care about adding directory // Directory prop will be something like "Win32_Directory.Name=\"C:\\\\\"" string dir = moMP["Directory"].ToString(); // find opening/closing quotes in order to get the substring we want int first = dir.IndexOf('"') + 1; int last = dir.LastIndexOf('"'); string dirSubstr = dir.Substring(first , last - first); // use GetFullPath to normalize/unescape any extra backslashes string fullpath = Path.GetFullPath(dirSubstr); ret[devId].Add(MOUNTPOINT_DIRS_KEY, fullpath); } } } } } } catch (Exception ex) { Console.WriteLine("Problem retrieving Volume information from WMI. {0} - \n{1}",ex.Message,ex.StackTrace); return ret; } return ret; }

  Read the article

• C# Monte Carlo Incremental Risk Calculation optimisation, random numbers, parallel execution

  - by m3ntat

  My current task is to optimise a Monte Carlo Simulation that calculates Capital Adequacy figures by region for a set of Obligors. It is running about 10 x too slow for where it will need to be in production and number or daily runs required. Additionally the granularity of the result figures will need to be improved down to desk possibly book level at some stage, the code I've been given is basically a prototype which is used by business units in a semi production capacity. The application is currently single threaded so I'll need to make it multi-threaded, may look at System.Threading.ThreadPool or the Microsoft Parallel Extensions library but I'm constrained to .NET 2 on the server at this bank so I may have to consider this guy's port, http://www.codeproject.com/KB/cs/aforge_parallel.aspx. I am trying my best to get them to upgrade to .NET 3.5 SP1 but it's a major exercise in an organisation of this size and might not be possible in my contract time frames. I've profiled the application using the trial of dotTrace (http://www.jetbrains.com/profiler). What other good profilers exist? Free ones? A lot of the execution time is spent generating uniform random numbers and then translating this to a normally distributed random number. They are using a C# Mersenne twister implementation. I am not sure where they got it or if it's the best way to go about this (or best implementation) to generate the uniform random numbers. Then this is translated to a normally distributed version for use in the calculation (I haven't delved into the translation code yet). Also what is the experience using the following? http://quantlib.org http://www.qlnet.org (C# port of quantlib) or http://www.boost.org Any alternatives you know of? I'm a C# developer so would prefer C#, but a wrapper to C++ shouldn't be a problem, should it? Maybe even faster leveraging the C++ implementations. I am thinking some of these libraries will have the fastest method to directly generate normally distributed random numbers, without the translation step. Also they may have some other functions that will be helpful in the subsequent calculations. Also the computer this is on is a quad core Opteron 275, 8 GB memory but Windows Server 2003 Enterprise 32 bit. Should I advise them to upgrade to a 64 bit OS? Any links to articles supporting this decision would really be appreciated. Anyway, any advice and help you may have is really appreciated.

  Read the article

• CruiseControl.Net Publisher email failing to send e-mail

  - by CrimsonX

  So here's my problem: I cannot seem to be able to configure CruiseControl.NET to send out an e-mail to me when a build occurs. I copied the example from the documentation and filled it in with my own values. http://confluence.public.thoughtworks.org/display/CCNET/Email+Publisher Here's the relevant section of ccnet.config below <publishers> <merge> <files> <file>C:\Build\Temp\*.xml</file> </files> </merge> <xmllogger logDir="buildlogs" /> <statistics> <statisticList> <statistic /> </statisticList> </statistics> <email includeDetails="TRUE" mailhostUsername="user" mailhostPassword="password" useSSL="TRUE"> <from>[email protected]</from> <mailhost>mail.mycompanysmtpserver.com</mailhost> <users> <user name="MyName Lastname" group="buildmaster" address="[email protected]" /> </users> <groups> <group name="buildmaster"> <notifications> <notificationType>Always</notificationType> </notifications> </group> </groups> <modifierNotificationTypes> <NotificationType>Failed</NotificationType> <NotificationType>Fixed</NotificationType> </modifierNotificationTypes> <subjectSettings> <subject buildResult="StillBroken" value="Build is still broken for {CCNetProject}" /> </subjectSettings> </email> </publishers> I have had a successful CruiseControl.NET server configured for some time, and it successfully updates people through CCTray, but I need to add e-mail support as well. I've already looked at the relevant StackOverflow articles like this one and many more and tried my hand at googling the solution but I dont know what I could be doing wrong. The only other thing that I'd like to validate is that I can send/receive e-mails using my username/password with the SMTP server I received from IT (my mail works properly) but I just followed the steps on testing an SMTP server here and everything looks fine http://support.microsoft.com/kb/153119 Anyone have any ideas as to why I'm getting this problem, or how to troubleshoot it further?

  Read the article

• Tactics for using PHP in a high-load site

  - by Ross

  Before you answer this I have never developed anything popular enough to attain high server loads. Treat me as (sigh) an alien that has just landed on the planet, albeit one that knows PHP and a few optimisation techniques. I'm developing a tool in PHP that could attain quite a lot of users, if it works out right. However while I'm fully capable of developing the program I'm pretty much clueless when it comes to making something that can deal with huge traffic. So here's a few questions on it (feel free to turn this question into a resource thread as well). Databases At the moment I plan to use the MySQLi features in PHP5. However how should I setup the databases in relation to users and content? Do I actually need multiple databases? At the moment everything's jumbled into one database - although I've been considering spreading user data to one, actual content to another and finally core site content (template masters etc.) to another. My reasoning behind this is that sending queries to different databases will ease up the load on them as one database = 3 load sources. Also would this still be effective if they were all on the same server? Caching I have a template system that is used to build the pages and swap out variables. Master templates are stored in the database and each time a template is called it's cached copy (a html document) is called. At the moment I have two types of variable in these templates - a static var and a dynamic var. Static vars are usually things like page names, the name of the site - things that don't change often; dynamic vars are things that change on each page load. My question on this: Say I have comments on different articles. Which is a better solution: store the simple comment template and render comments (from a DB call) each time the page is loaded or store a cached copy of the comments page as a html page - each time a comment is added/edited/deleted the page is recached. Finally Does anyone have any tips/pointers for running a high load site on PHP. I'm pretty sure it's a workable language to use - Facebook and Yahoo! give it great precedence - but are there any experiences I should watch out for? Thanks, Ross

  Read the article

• What Is The Best Database For Delphi Desktop Applications That Supports Stored Procedures?

  - by Cape Cod Gunny

  I started with Turbo Pascal 3, went to TP5, Bought TP6 called Borland the next day and downgraded to TP5.5. Bought Delphi 3, and now have Delphi 5 Enterprise. I sort of lost interest in writing code about 4-5 years ago for two reasons; Spent all day writing ASP & SQL for someone else. PC Techniques magazine went away. I've got a few programs in the shareware market that are solid performers but are in need of serious updating. I love Delphi or did when it was Borland (before Borland bought DBase and all the other crap), I'd like to salvage as much of my D5E code as possible but I doubt I can. I plan on upgrading to Delphi 2010. My next software release needs to interact with a database. I'm very proficient with MS Sql and like to put all of the database code in stored procedures. What is the best database choice that interacts well with Delphi, allows stored procedures and is so easy to deploy that even the Geico gecko could deploy it? 10/25/2009 18:53 PM EST Re-Opened After Reading Install Docs for Delphi 2010 I downloaded a trial version of Delphi 2010 and unzipped the install. I've been reading the install docs included in the package. I started with the install.htm inside the zip package. install.htm wisely tells you to see the following two articles: Installation Notes: http://edn.embarcadero.com/article/39754 Release Notes: http://edn.embarcadero.com/article/39758 the release notes state the following... MSSQL driver requires the installation of the SQL Native Client. SQL Native Client 2008 is required for dbxmss.dll. SQL Native Client 2005 is required for dbxmss9.dll I checked my machine to see if SQL Native Client is installed. Nope. I wasn't done reading the docs so I made a note to install SQL Native Client. I googled dbxmss.dll and dbxmss9.dll and found a very interesting thread on the Embarcadero forums. read thread here. After reading this thread and some careful thought I don't think I will be using Microsoft SQL Express. I can't rely on my customers having the right drivers installed. So, I'm back to looking for a different solution. If I'm selling a $40 product to the general masses I need to have a bulletproof solution that doesn't require my brand new customer to update their machine before my software will work.

  Read the article

< Previous Page | 375 376 377 378 379 380 381 382 383 384 385 386  | Next Page >