Search Results

Search found 6587 results on 264 pages for 'slow motion'.

Page 138/264 | < Previous Page | 134 135 136 137 138 139 140 141 142 143 144 145  | Next Page >

  • Are Chromebooks the New Netbooks, and What Does That Mean?

    - by Chris Hoffman
    Netbooks — small, cheap, slow laptops — were once very popular. They fell out of favor — people bought them because they seemed cheap and portable, but the actual experience was lackluster. Most netbooks now sit unused. Windows netbooks have vanished from stores today, but there’s a new super-cheap laptop — the Chromebook. Chromebook sales numbers are impressive, but their usage statistics tell a different story. Are Chromebooks just the new netbook? The Problem With Netbooks Netbooks seemed appealing, especially in an age before tablets and lightweight ultrabooks. You could buy a netbook for $200 or so and have a portable device that let you get on the Internet. The name “netbook” spelled that out — it was a portable device for getting on the ‘net. They weren’t really that great. The original netbook was a lightweight Asus Eee PC that ran Linux alone and had a small amount of fast flash storage. Netbooks eventually ran heavier Windows XP operating systems — Windows Vista was out, but it was just too bloated to run on netbooks. Manufacturers added slow magnetic hard drives, bloatware, and even DVD drives! They couldn’t run most Windows software very well. The build quality was poor and their keyboards were tiny and cramped. People liked the idea of a lightweight device that let them get on the Internet and loved the cheap price, but the actual experience wasn’t great. Chromebook Sales Chromebook sales numbers seem surprisingly high. NPD reported that Chromebooks were 21% of all notebooks sold in the US in 2013. If you combine laptop and tablet sales into a single statistic, Chromebooks were 9.6% of all those devices sold. That’s 2/3 as many Chromebooks sold as iPads in the US! Of Amazon’s best-selling laptop computers, two of the top three are Chromebooks. These definitely look like successful products. Unlike netbooks, Chromebooks are taking off in a big way in the education market. Many schools are buying Chromebooks for their students instead of more expensive Windows laptops. They’re easier to manage and lock down than Windows laptops, but — more importantly for cash-strapped schools — they’re very cheap. Netbooks never had this sort of momentum in schools. Chromebook Usage Statistics Here’s where the rosy picture of Chromebooks starts to become more realistic. StatCounter’s browser usage statistics show how widely used different operating systems are. For example, Windows 7 has the highest share with 35.71% of web activity in April, 2014. The chart doesn’t even show Chrome OS at all, although there is an “Other” number near the bottom. Click the Download Data link to download a CSV file and we can view more detailed information. Chrome OS only accounted for 0.38% of web usage in April, 2014. Desktop Linux, which people often shrug at, accounted for 1.52% in the same month. To its credit, Chrome OS usage has increased. Chromebooks were widely mocked back in November, 2013 when the sales numbers came out. After all, they only accounted for 0.11% of web usage globally in November, 2013! But Chrome OS numbers have been improving: Nov, 2013: 0.11% Dec, 2013: 0.22% Jan, 2014: 0.31% Feb, 2014: 0.35% Mar, 2014: 0.36% Apr, 2014: 0.38% Chrome OS is climbing, but it’s definitely still in the “Other” category. It isn’t as high as we’d expect to see it with those types of sales numbers. Chromebooks vs. Netbooks Chromebooks are more limited devices than traditional PCs. You can do quite a few things, but you have to do it all using Chrome or Chrome apps. Most people won’t be enabling developer mode and installing a Linux desktop. You don’t have access to the powerful desktop software available for Windows and even Mac OS X. On the other hand, these Chromebooks are less compromised than netbooks in many ways. They come with a lightweight operating system designed for portable, mobile devices. They don’t come packed with any bloatware, like the bloatware you’ll find on competing Windows PCs and the original netbooks. They’re cheaper because the manufacturer doesn’t have to pay for a Windows license. There’s no need for antivirus software weighing the operating system down. They’re larger than the original netbooks, with many of them being 11.6-inches instead of the original 8-inch bodies many older netbooks came with. They have larger, more comfortable keyboards and fast solid-state storage. Really, Chromebooks are what netbooks wanted to be. People didn’t buy netbooks to use typical Windows software — they just wanted a lightweight PC. Of course, for many people, the real successor to netbooks is tablets. If all you want is a portable device to throw in a bag so you can get online, maybe a tablet is better. Where Does This Leave Chromebooks? So, are Chromebooks the new netbooks? It’s a bit early to answer that question. Chromebooks are definitely not out of the competition — their sales look good and their usage share is increasing. On the other hand, Chrome OS is still pretty far behind. They’re not catching fire like tablets did. Maybe netbooks were just before their time and Chromebooks were what they were always meant to be. Just as Microsoft’s Windows XP tablets failed, Windows XP netbooks also failed. Tablets took off with a more refined operating system on better hardware years later. “Netbooks” — or Chromebooks — are now taking off with a more purpose-built operating system on better hardware, too. It’s hard to count Chromebooks out because they provide a much better experience than netbooks ever did. If you’re one of the people who wants to use old Windows desktop apps on your portable laptop, you may think netbooks were better — but most people don’t want that. But maybe people either want a full desktop PC experience or a full mobile tablet experience. Is there a place for a laptop with a keyboard that can only view websites? We’ll have to wait and see. Image Credit: Kevin Jarret on Flickr, Clive Darra on Flickr, Sean Freese on Flickr

    Read the article

  • Developing Schema Compare for Oracle (Part 1)

    - by Simon Cooper
    SQL Compare is one of Red Gate's most successful SQL Server tools; it allows developers and DBAs to compare and synchronize the contents of their databases. Although similar tools exist for Oracle, they are quite noticeably lacking in the usability and stability that SQL Compare is known for in the SQL Server world. We could see a real need for a usable schema comparison tools for Oracle, and so the Schema Compare for Oracle project was born. Over the next few weeks, as we come up to release of v1, I'll be doing a series of posts on the development of Schema Compare for Oracle. For the first post, I thought I would start with the main pitfalls that we stumbled across when developing the product, especially from a SQL Server background. 1. Schemas and Databases The most obvious difference is that the concept of a 'database' is quite different between Oracle and SQL Server. On SQL Server, one server instance has multiple databases, each with separate schemas. There is typically little communication between separate databases, and most databases are no more than about 1000-2000 objects. This means SQL Compare can register an entire database in a reasonable amount of time, and cross-database dependencies probably won't be an issue. It is a quite different scene under Oracle, however. The terms 'database' and 'instance' are used interchangeably, (although technically 'database' refers to the datafiles on disk, and 'instance' the running Oracle process that reads & writes to the database), and a database is a single conceptual entity. This immediately presents problems, as it is infeasible to register an entire database as we do in SQL Compare; in my Oracle install, using the standard recommended options, there are 63975 system objects. If we tried to register all those, not only would it take hours, but the client would probably run out of memory before we finished. As a result, we had to allow people to specify what schemas they wanted to register. This decision had quite a few knock-on effects for the design, which I will cover in a future post. 2. Connecting to Oracle The next obvious difference is in actually connecting to Oracle – in SQL Server, you can specify a server and database, and off you go. On Oracle things are slightly more complicated. SIDs, Service Names, and TNS A database (the files on disk) must have a unique identifier for the databases on the system, called the SID. It also has a global database name, which consists of a name (which doesn't have to match the SID) and a domain. Alternatively, you can identify a database using a service name, which normally has a 1-to-1 relationship with instances, but may not if, for example, using RAC (Real Application Clusters) for redundancy and failover. You specify the computer and instance you want to connect to using TNS (Transparent Network Substrate). The user-visible parts are a config file (tnsnames.ora) on the client machine that specifies how to connect to an instance. For example, the entry for one of my test instances is: SC_11GDB1 = (DESCRIPTION = (ADDRESS_LIST = (ADDRESS = (PROTOCOL = TCP)(HOST = simonctest)(PORT = 1521)) ) (CONNECT_DATA = (SID = 11gR1db1) ) ) This gives the hostname, port, and SID of the instance I want to connect to, and associates it with a name (SC_11GDB1). The tnsnames syntax also allows you to specify failover, multiple descriptions and address lists, and client load balancing. You can then specify this TNS identifier as the data source in a connection string. Although using ODP.NET (the .NET dlls provided by Oracle) was fine for internal prototype builds, once we released the EAP we discovered that this simply wasn't an acceptable solution for installs on other people's machines. Due to .NET assembly strong naming, users had to have installed on their machines the exact same version of the ODP.NET dlls as we had on our build server. We couldn't ship the ODP.NET dlls with our installer as the Oracle license agreement prohibited this, and we didn't want to force users to install another Oracle client just so they can run our program. To be able to list the TNS entries in the connection dialog, we also had to locate and parse the tnsnames.ora file, which was complicated by users with several Oracle client installs and intricate TNS entries. After much swearing at our computers, we eventually decided to use a third party Oracle connection library from Devart that we could ship with our program; this could use whatever client version was installed, parse the TNS entries for us, and also had the nice feature of being able to connect to an Oracle server without having any client installed at all. Unfortunately, their current license agreement prevents us from shipping an Oracle SDK, but that's a bridge we'll cross when we get to it. 3. Running synchronization scripts The most important difference is that in Oracle, DDL is non-transactional; you cannot rollback DDL statements like you can on SQL Server. Although we considered various solutions to this, including using the flashback archive or recycle bin, or generating an undo script, no reliable method of completely undoing a half-executed sync script has yet been found; so in this case we simply have to trust that the DBA or developer will check and verify the script before running it. However, before we got to that stage, we had to get the scripts to run in the first place... To run a synchronization script from SQL Compare we essentially pass the script over to the SqlCommand.ExecuteNonQuery method. However, when we tried to do the same for an OracleConnection we got a very strange error – 'ORA-00911: invalid character', even when running the most basic CREATE TABLE command. After much hair-pulling and Googling, we discovered that Oracle has got some very strange behaviour with semicolons at the end of statements. To understand what's going on, we need to take a quick foray into SQL and PL/SQL. PL/SQL is not T-SQL In SQL Server, T-SQL is the language used to interface with the database. It has DDL, DML, control flow, and many other nice features (like Turing-completeness) that you can mix and match in the same script. In Oracle, DDL SQL and PL/SQL are two completely separate languages, with different syntax, different datatypes and different execution engines within the instance. Oracle SQL is much more like 'pure' ANSI SQL, with no state, no control flow, and only the basic DML commands. PL/SQL is the Turing-complete language, but can only do DML and DCL (i.e. BEGIN TRANSATION commands). Any DDL or SQL commands that aren't recognised by the PL/SQL engine have to be passed back to the SQL engine via an EXECUTE IMMEDIATE command. In PL/SQL, a semicolons is a valid token used to delimit the end of a statement. In SQL, a semicolon is not a valid token (even though the Oracle documentation gives them at the end of the syntax diagrams) . When you execute the command CREATE TABLE table1 (COL1 NUMBER); in SQL*Plus the semicolon on the end is a command to SQL*Plus to execute the preceding statement on the server; it strips off the semicolon before passing it on. SQL Developer does a similar thing. When executing a PL/SQL block, however, the syntax is like so: BEGIN INSERT INTO table1 VALUES (1); INSERT INTO table1 VALUES (2); END; / In this case, the semicolon is accepted by the PL/SQL engine as a statement delimiter, and instead the / is the command to SQL*Plus to execute the current block. This explains the ORA-00911 error we got when trying to run the CREATE TABLE command – the server is complaining about the semicolon on the end. This also means that there is no SQL syntax to execute more than one DDL command in the same OracleCommand. Therefore, we would have to do a round-trip to the server for every command we want to execute. Obviously, this would cause lots of network traffic and be very slow on slow or congested networks. Our first attempt at a solution was to wrap every SQL statement (without semicolon) inside an EXECUTE IMMEDIATE command in a PL/SQL block and pass that to the server to execute. One downside of this solution is that we get no feedback as to how the script execution is going; we're currently evaluating better solutions to this thorny issue. Next up: Dependencies; how we solved the problem of being unable to register the entire database, and the knock-on effects to the whole product.

    Read the article

  • Top 10 Browser Productivity Tips

    - by Renso
    Originally posted on: http://geekswithblogs.net/renso/archive/2013/10/14/top-10-browser-productivity-tips.aspxYou don’t have to be a geek to be a productive browser user. The tips below have been selected by actions users take most of the time to navigate a web-site but use long-standing keyboard or mouse actions to get them done, when there are keyboard short-cuts you can use instead. Since you hands are already on the keyboard it is almost always faster to sue a keyboard shortcut to get something done that you usually used the mouse for. For example right-clicking on something to copy it and then doing to same for pasting something is very time consuming, keyboard shortcuts have been created that simplify the task. All it takes are a few memory brain cells to remember them. Here are the tips, in no particular order:   Tip 1 Hold down the spacebar on your keyboard to page to the end of your web page rather than using your mouse. This is really a slow way of doing it. If you want to page one page at a time, hit the spacebar once, and again to page again. But if you want to page all the way to the end of the web page simply hit Ctrl+End (that is hold down the Ctrl key and hit the End button on your keyboard). To get to the top of your web page, simply hit Ctrl + Home to go all the way to the top of your web page. Tip 2 Where are my downloads? Some folks run downloads again-and-again because they do not know where the last one went and they do not see the popup, or browser note on their web page in the footer, etc. Simply hit Ctrl+J. Works in most browsers. Tip 3 Selecting a US state from a drop down box. Don’t use the mouse, takes just way too long to scroll. When you tab to the drop down box or click on it with your mouse, simply hit the first character of the state and it will be selected. For Texas for example hit the letter “T” twice on your keyboard to get to it. The same concept can be applied to any drop down box that is alphabetical or numerically sorted. Tip 4 Fixing spelling errors. All modern-day browsers support this now. You see the red wavy lines underscoring a word, yes it is a spelling error. How do you fix it? Don’t overtype it or try and fix it manually, fist right-click on it and a list of suggestions comes up. If it does not show up, like my name “Renso” and you know how to spell your name as in this example, look further down the list of options (the little window popup that appears when you right click) and you should see an option to “Add to Dictionary”. Be warned, when you add it, it only adds it to the browser you’re using’s dictionary. If you use Google Chrome, Firefox and IE, each one will have their own list. Tip 5 So you have trouble seeing the text on the screen. Or you are looking at a photo, for example in Facebook. You want to zoom in to read better or zoom into a photo a bit more. Hit Ctrl++ (hold down Ctrl key and hit the plus key – actually it’s the equal key but it is easier to remember that it is plus for bigger). Hit the minus to zoom out. Now you can’t remember what the original size was since you were so excited to hit it 20 times, or was that 21… Simply hit Ctrl+0 (that is zero) and it will reset it to the default. Tip 6 So you closed a couple of tabs in your browser. Suddenly you remember something you wanted to double-check something on one of the tabs, you cannot remember the URL ad the tab is gone forever, or is it? Simply hit Ctrl+Shift+t and it will bring back your tabs one by one each time you click the T. This has also been a great way for me to quickly close some tabs because I don’t want my boss to see I’m shopping and then hitting Ctrl+Shift+t to quickly get it back and complete my check-put and purchase. Or, for parents, when you walk into your daughter’s room and you see she quickly clicks and closes a window/tab in here browser. Not to worry my little darling, daddy will Ctrl+Shift+t and see what boys on Facebook you were talking too… Tip 7 The web browser is frozen on your PC/Laptop/Whatever, in this example it may be your Internet Explorer browser. I don’t mention Firefox or Chrome here because it probably never happens in their world. You cannot close it, it won’t respond to anything you have done s far except for the next step you are about to take, which is throw your two-day old coffee on your keyboard. This happens especially on sites that want to force you to complete a purchase order. Hit Ctrl+Alt+Del on your keyboard on any version of windows, select TASK MANAGER. In the  First Tab, which is the Process Tab, look for the item in question. In this example you should see Internet Explorer. Right-click it and select “End Task”. It will force the thread out of memory and terminate that process. You can of course do this with any program running under your account. Tip 8 This is a personal favorite of mine. To select words in the paragraph without using the mouse. You don’t want to select one character at a time like when you use the Ctrl+arrows as it can be very slow if you want to select a lot of text. You also want to select whole words. Simply use the Ctrl+Shift_arrow (right or left depending which direction you want to go. Tip 9 I was a bit reluctant to add this one, but being in the professional services industry still come across many-a-folk that simply can’t copy-and-paste them-all text or images that reside on them screens, y’all. Ctrl+c to copy and Ctrl+v to paste it. Works a lot faster than using the mouse. You may be asking: “Well why in the devil did they not use Ctrl+p for paste…. because that is for printing. This is of course not limited to the browser world, it applies to almost any piece of software running on PC or Mac. Go try it on an image on your browser, right-click it and select copy. Open a word document and Ctrl+v to paste the image in there. Please consider copyright laws. Tip 10 Getting rid of annoying ads. Now this only works when you load a web page, meaning when you get back to the same page later you will have to do this again and you will need to learn a tool to do it, WELL WORTH IT. For example, I use GrooveShark to listen to music but I don’t like the ads they show. Install a tool like Firebug for Firefox or use the Ctrl+Shift+I on Chrome to bring up the developer toolbar. Shows at the bottom of the page. With Firefox, once you have installed Firebug as an add-on, a yellow bug should appear on the top right-hand-side of your browser, click on it to display the developer toolbar. You will need to learn how to use it, but once you know how to select an item/section on the window (usually just right-click the add you don’t want to see and select “Inspect Element”, the developer toolbar will appear (if not already there)) and then simply hit delete and it will remove the add from the screen. If you don’t know HTML you may need to play with it a bit, but once you understand how it works can open up a whole new world for you on how web pages actually work. If you can think of any others that have saved you a ton of time please let me know so I can add them to a top 99 list.

    Read the article

  • HTG Explains: Why Does Rebooting a Computer Fix So Many Problems?

    - by Chris Hoffman
    Ask a geek how to fix a problem you’ve having with your Windows computer and they’ll likely ask “Have you tried rebooting it?” This seems like a flippant response, but rebooting a computer can actually solve many problems. So what’s going on here? Why does resetting a device or restarting a program fix so many problems? And why don’t geeks try to identify and fix problems rather than use the blunt hammer of “reset it”? This Isn’t Just About Windows Bear in mind that this soltion isn’t just limited to Windows computers, but applies to all types of computing devices. You’ll find the advice “try resetting it” applied to wireless routers, iPads, Android phones, and more. This same advice even applies to software — is Firefox acting slow and consuming a lot of memory? Try closing it and reopening it! Some Problems Require a Restart To illustrate why rebooting can fix so many problems, let’s take a look at the ultimate software problem a Windows computer can face: Windows halts, showing a blue screen of death. The blue screen was caused by a low-level error, likely a problem with a hardware driver or a hardware malfunction. Windows reaches a state where it doesn’t know how to recover, so it halts, shows a blue-screen of death, gathers information about the problem, and automatically restarts the computer for you . This restart fixes the blue screen of death. Windows has gotten better at dealing with errors — for example, if your graphics driver crashes, Windows XP would have frozen. In Windows Vista and newer versions of Windows, the Windows desktop will lose its fancy graphical effects for a few moments before regaining them. Behind the scenes, Windows is restarting the malfunctioning graphics driver. But why doesn’t Windows simply fix the problem rather than restarting the driver or the computer itself?  Well, because it can’t — the code has encountered a problem and stopped working completely, so there’s no way for it to continue. By restarting, the code can start from square one and hopefully it won’t encounter the same problem again. Examples of Restarting Fixing Problems While certain problems require a complete restart because the operating system or a hardware driver has stopped working, not every problem does. Some problems may be fixable without a restart, though a restart may be the easiest option. Windows is Slow: Let’s say Windows is running very slowly. It’s possible that a misbehaving program is using 99% CPU and draining the computer’s resources. A geek could head to the task manager and look around, hoping to locate the misbehaving process an end it. If an average user encountered this same problem, they could simply reboot their computer to fix it rather than dig through their running processes. Firefox or Another Program is Using Too Much Memory: In the past, Firefox has been the poster child for memory leaks on average PCs. Over time, Firefox would often consume more and more memory, getting larger and larger and slowing down. Closing Firefox will cause it to relinquish all of its memory. When it starts again, it will start from a clean state without any leaked memory. This doesn’t just apply to Firefox, but applies to any software with memory leaks. Internet or Wi-Fi Network Problems: If you have a problem with your Wi-Fi or Internet connection, the software on your router or modem may have encountered a problem. Resetting the router — just by unplugging it from its power socket and then plugging it back in — is a common solution for connection problems. In all cases, a restart wipes away the current state of the software . Any code that’s stuck in a misbehaving state will be swept away, too. When you restart, the computer or device will bring the system up from scratch, restarting all the software from square one so it will work just as well as it was working before. “Soft Resets” vs. “Hard Resets” In the mobile device world, there are two types of “resets” you can perform. A “soft reset” is simply restarting a device normally — turning it off and then on again. A “hard reset” is resetting its software state back to its factory default state. When you think about it, both types of resets fix problems for a similar reason. For example, let’s say your Windows computer refuses to boot or becomes completely infected with malware. Simply restarting the computer won’t fix the problem, as the problem is with the files on the computer’s hard drive — it has corrupted files or malware that loads at startup on its hard drive. However, reinstalling Windows (performing a “Refresh or Reset your PC” operation in Windows 8 terms) will wipe away everything on the computer’s hard drive, restoring it to its formerly clean state. This is simpler than looking through the computer’s hard drive, trying to identify the exact reason for the problems or trying to ensure you’ve obliterated every last trace of malware. It’s much faster to simply start over from a known-good, clean state instead of trying to locate every possible problem and fix it. Ultimately, the answer is that “resetting a computer wipes away the current state of the software, including any problems that have developed, and allows it to start over from square one.” It’s easier and faster to start from a clean state than identify and fix any problems that may be occurring — in fact, in some cases, it may be impossible to fix problems without beginning from that clean state. Image Credit: Arria Belli on Flickr, DeclanTM on Flickr     

    Read the article

  • DBA Best Practices - A Blog Series: Episode 1 - Backups

    - by Argenis
      This blog post is part of the DBA Best Practices series, on which various topics of concern for daily database operations are discussed. Your feedback and comments are very much welcome, so please drop by the comments section and be sure to leave your thoughts on the subject. Morning Coffee When I was a DBA, the first thing I did when I sat down at my desk at work was checking that all backups had completed successfully. It really was more of a ritual, since I had a dual system in place to check for backup completion: 1) the scheduled agent jobs to back up the databases were set to alert the NOC in failure, and 2) I had a script run from a central server every so often to check for any backup failures. Why the redundancy, you might ask. Well, for one I was once bitten by the fact that database mail doesn't work 100% of the time. Potential causes for failure include issues on the SMTP box that relays your server email, firewall problems, DNS issues, etc. And so to be sure that my backups completed fine, I needed to rely on a mechanism other than having the servers do the taking - I needed to interrogate the servers and ask each one if an issue had occurred. This is why I had a script run every so often. Some of you might have monitoring tools in place like Microsoft System Center Operations Manager (SCOM) or similar 3rd party products that would track all these things for you. But at that moment, we had no resort but to write our own Powershell scripts to do it. Now it goes without saying that if you don't have backups in place, you might as well find another career. Your most sacred job as a DBA is to protect the data from a disaster, and only properly safeguarded backups can offer you peace of mind here. "But, we have a cluster...we don't need backups" Sadly I've heard this line more than I would have liked to. You need to understand that a cluster is comprised of shared storage, and that is precisely your single point of failure. A cluster will protect you from an issue at the Operating System level, and also under an outage of any SQL-related service or dependent devices. But it will most definitely NOT protect you against corruption, nor will it protect you against somebody deleting data from a table - accidentally or otherwise. Backup, fine. How often do I take a backup? The answer to this is something you will hear frequently when working with databases: it depends. What does it depend on? For one, you need to understand how much data your business is willing to lose. This is what's called Recovery Point Objective, or RPO. If you don't know how much data your business is willing to lose, you need to have an honest and realistic conversation about data loss expectations with your customers, internal or external. From my experience, their first answer to the question "how much data loss can you withstand?" will be "zero". In that case, you will need to explain how zero data loss is very difficult and very costly to achieve, even in today's computing environments. Do you want to go ahead and take full backups of all your databases every hour, or even every day? Probably not, because of the impact that taking a full backup can have on a system. That's what differential and transaction log backups are for. Have I answered the question of how often to take a backup? No, and I did that on purpose. You need to think about how much time you have to recover from any event that requires you to restore your databases. This is what's called Recovery Time Objective. Again, if you go ask your customer how long of an outage they can withstand, at first you will get a completely unrealistic number - and that will be your starting point for discussing a solution that is cost effective. The point that I'm trying to get across is that you need to have a plan. This plan needs to be practiced, and tested. Like a football playbook, you need to rehearse the moves you'll perform when the time comes. How often is up to you, and the objective is that you feel better about yourself and the steps you need to follow when emergency strikes. A backup is nothing more than an untested restore Backups are files. Files are prone to corruption. Put those two together and realize how you feel about those backups sitting on that network drive. When was the last time you restored any of those? Restoring your backups on another box - that, by the way, doesn't have to match the specs of your production server - will give you two things: 1) peace of mind, because now you know that your backups are good and 2) a place to offload your consistency checks with DBCC CHECKDB or any of the other DBCC commands like CHECKTABLE or CHECKCATALOG. This is a great strategy for VLDBs that cannot withstand the additional load created by the consistency checks. If you choose to offload your consistency checks to another server though, be sure to run DBCC CHECKDB WITH PHYSICALONLY on the production server, and if you're using SQL Server 2008 R2 SP1 CU4 and above, be sure to enable traceflags 2562 and/or 2549, which will speed up the PHYSICALONLY checks further - you can read more about this enhancement here. Back to the "How Often" question for a second. If you have the disk, and the network latency, and the system resources to do so, why not backup the transaction log often? As in, every 5 minutes, or even less than that? There's not much downside to doing it, as you will have to clear the log with a backup sooner than later, lest you risk running out space on your tlog, or even your drive. The one drawback to this approach is that you will have more files to deal with at restore time, and processing each file will add a bit of extra time to the entire process. But it might be worth that time knowing that you minimized the amount of data lost. Again, test your plan to make sure that it matches your particular needs. Where to back up to? Network share? Locally? SAN volume? This is another topic where everybody has a favorite choice. So, I'll stick to mentioning what I like to do and what I consider to be the best practice in this regard. I like to backup to a SAN volume, i.e., a drive that actually lives in the SAN, and can be easily attached to another server in a pinch, saving you valuable time - you wouldn't need to restore files on the network (slow) or pull out drives out a dead server (been there, done that, it’s also slow!). The key is to have a copy of those backup files made quickly, and, if at all possible, to a remote target on a different datacenter - or even the cloud. There are plenty of solutions out there that can help you put such a solution together. That right there is the first step towards a practical Disaster Recovery plan. But there's much more to DR, and that's material for a different blog post in this series.

    Read the article

  • DBA Best Practices - A Blog Series: Episode 1 - Backups

    - by Argenis
      This blog post is part of the DBA Best Practices series, on which various topics of concern for daily database operations are discussed. Your feedback and comments are very much welcome, so please drop by the comments section and be sure to leave your thoughts on the subject. Morning Coffee When I was a DBA, the first thing I did when I sat down at my desk at work was checking that all backups have completed successfully. It really was more of a ritual, since I had a dual system in place to check for backup completion: 1) the scheduled agent jobs to back up the databases were set to alert the NOC in failure, and 2) I had a script run from a central server every so often to check for any backup failures. Why the redundancy, you might ask. Well, for one I was once bitten by the fact that database mail doesn't work 100% of the time. Potential causes for failure include issues on the SMTP box that relays your server email, firewall problems, DNS issues, etc. And so to be sure that my backups completed fine, I needed to rely on a mechanism other than having the servers do the taking - I needed to interrogate the servers and ask each one if an issue had occurred. This is why I had a script run every so often. Some of you might have monitoring tools in place like Microsoft System Center Operations Manager (SCOM) or similar 3rd party products that would track all these things for you. But at that moment, we had no resort but to write our own Powershell scripts to do it. Now it goes without saying that if you don't have backups in place, you might as well find another career. Your most sacred job as a DBA is to protect the data from a disaster, and only properly safeguarded backups can offer you peace of mind here. "But, we have a cluster...we don't need backups" Sadly I've heard this line more than I would have liked to. You need to understand that a cluster is comprised of shared storage, and that is precisely your single point of failure. A cluster will protect you from an issue at the Operating System level, and also under an outage of any SQL-related service or dependent devices. But it will most definitely NOT protect you against corruption, nor will it protect you against somebody deleting data from a table - accidentally or otherwise. Backup, fine. How often do I take a backup? The answer to this is something you will hear frequently when working with databases: it depends. What does it depend on? For one, you need to understand how much data your business is willing to lose. This is what's called Recovery Point Objective, or RPO. If you don't know how much data your business is willing to lose, you need to have an honest and realistic conversation about data loss expectations with your customers, internal or external. From my experience, their first answer to the question "how much data loss can you withstand?" will be "zero". In that case, you will need to explain how zero data loss is very difficult and very costly to achieve, even in today's computing environments. Do you want to go ahead and take full backups of all your databases every hour, or even every day? Probably not, because of the impact that taking a full backup can have on a system. That's what differential and transaction log backups are for. Have I answered the question of how often to take a backup? No, and I did that on purpose. You need to think about how much time you have to recover from any event that requires you to restore your databases. This is what's called Recovery Time Objective. Again, if you go ask your customer how long of an outage they can withstand, at first you will get a completely unrealistic number - and that will be your starting point for discussing a solution that is cost effective. The point that I'm trying to get across is that you need to have a plan. This plan needs to be practiced, and tested. Like a football playbook, you need to rehearse the moves you'll perform when the time comes. How often is up to you, and the objective is that you feel better about yourself and the steps you need to follow when emergency strikes. A backup is nothing more than an untested restore Backups are files. Files are prone to corruption. Put those two together and realize how you feel about those backups sitting on that network drive. When was the last time you restored any of those? Restoring your backups on another box - that, by the way, doesn't have to match the specs of your production server - will give you two things: 1) peace of mind, because now you know that your backups are good and 2) a place to offload your consistency checks with DBCC CHECKDB or any of the other DBCC commands like CHECKTABLE or CHECKCATALOG. This is a great strategy for VLDBs that cannot withstand the additional load created by the consistency checks. If you choose to offload your consistency checks to another server though, be sure to run DBCC CHECKDB WITH PHYSICALONLY on the production server, and if you're using SQL Server 2008 R2 SP1 CU4 and above, be sure to enable traceflags 2562 and/or 2549, which will speed up the PHYSICALONLY checks further - you can read more about this enhancement here. Back to the "How Often" question for a second. If you have the disk, and the network latency, and the system resources to do so, why not backup the transaction log often? As in, every 5 minutes, or even less than that? There's not much downside to doing it, as you will have to clear the log with a backup sooner than later, lest you risk running out space on your tlog, or even your drive. The one drawback to this approach is that you will have more files to deal with at restore time, and processing each file will add a bit of extra time to the entire process. But it might be worth that time knowing that you minimized the amount of data lost. Again, test your plan to make sure that it matches your particular needs. Where to back up to? Network share? Locally? SAN volume? This is another topic where everybody has a favorite choice. So, I'll stick to mentioning what I like to do and what I consider to be the best practice in this regard. I like to backup to a SAN volume, i.e., a drive that actually lives in the SAN, and can be easily attached to another server in a pinch, saving you valuable time - you wouldn't need to restore files on the network (slow) or pull out drives out a dead server (been there, done that, it’s also slow!). The key is to have a copy of those backup files made quickly, and, if at all possible, to a remote target on a different datacenter - or even the cloud. There are plenty of solutions out there that can help you put such a solution together. That right there is the first step towards a practical Disaster Recovery plan. But there's much more to DR, and that's material for a different blog post in this series.

    Read the article

  • Slicing the EDG

    - by Antony Reynolds
    Different SOA Domain Configurations In this blog entry I would like to introduce three different configurations for a SOA environment.  I have omitted load balancers and OTD/OHS as they introduce a whole new round of discussion.  For each possible deployment architecture I have identified some of the advantages. Super Domain This is a single EDG style domain for everything needed for SOA/OSB.   It extends the standard EDG slightly but otherwise assumes a single “super” domain. This is basically the SOA EDG.  I have broken out JMS servers and Coherence servers to improve scalability and reduce dependencies. Key Points Separate JMS allows those servers to be kept up separately from rest of SOA Domain, allowing JMS clients to post messages even if rest of domain is unavailable. JMS servers are only used to host application specific JMS destinations, SOA/OSB JMS destinations remain in relevant SOA/OSB managed servers. Separate Coherence servers allow OSB cache to be offloaded from OSB servers. Use of Coherence by other components as a shared infrastructure data grid service. Coherence cluster may be managed by WLS but more likely run as a standalone Coherence cluster. Benefits Single Administration Point (1 Admin Server) Closely follows EDG with addition of application specific JMS servers and standalone Coherence servers for OSB caching and application specific caches. Coherence grid can be scaled independent of OSB/SOA. JMS queues provide for inter-application communication. Drawbacks Patching is an all or nothing affair. Startup time for SOA may be slow if large number of composites deployed. Multiple Domains This extends the EDG into multiple domains, allowing separate management and update of these domains.  I see this type of configuration quite often with customers, although some don't have OWSM, others don't have separate Coherence etc. SOA & BAM are kept in the same domain as little benefit is obtained by separating them. Key Points Separate JMS allows those servers to be kept up separately from rest of SOA Domain, allowing JMS clients to post messages even if other domains are unavailable. JMS servers are only used to host application specific JMS destinations, SOA/OSB JMS destinations remain in relevant SOA/OSB managed servers. Separate Coherence servers allow OSB cache to be offloaded from OSB servers. Use of Coherence by other components as a shared infrastructure data grid service. Coherence cluster may be managed by WLS but more likely run as a standalone Coherence cluster. Benefits Follows EDG but in separate domains and with addition of application specific JMS servers and standalone Coherence servers for OSB caching and application specific caches. Coherence grid can be scaled independent of OSB/SOA. JMS queues provide for inter-application communication. Patch lifecycle of OSB/SOA/JMS are no longer lock stepped. JMS may be kept running independently of other domains allowing applications to insert messages fro later consumption by SOA/OSB. OSB may be kept running independent of other domains, allowing service virtualization to continue independent of other domains availability. All domains use same OWSM policy store (MDS-WSM). Drawbacks Multiple domains to manage and configure. Multiple Admin servers (single view requires use of Grid Control) Multiple Admin servers/WSM clusters waste resources. Additional homes needed to enjoy benefits of separate patching. Cross domain trust needs setting up to simplify cross domain interactions. Startup time for SOA may be slow if large number of composites deployed. Shared Service Environment This model extends the previous multiple domain arrangement to provide a true shared service environment.This extends the previous model by allowing multiple additional SOA domains and/or other domains to take advantage of the shared services.  Only one non-shared domain is shown, but there could be multiple, allowing groups of applications to share patching independent of other application groups. Key Points Separate JMS allows those servers to be kept up separately from rest of SOA Domain, allowing JMS clients to post messages even if other domains are unavailable. JMS servers are only used to host application specific JMS destinations, SOA/OSB JMS destinations remain in relevant SOA/OSB managed servers. Separate Coherence servers allow OSB cache to be offloaded from OSB servers. Use of Coherence by other components as a shared infrastructure data grid service Coherence cluster may be managed by WLS but more likely run as a standalone Coherence cluster. Shared SOA Domain hosts Human Workflow Tasks BAM Common "utility" composites Single OSB domain provides "Enterprise Service Bus" All domains use same OWSM policy store (MDS-WSM) Benefits Follows EDG but in separate domains and with addition of application specific JMS servers and standalone Coherence servers for OSB caching and application specific caches. Coherence grid can be scaled independent of OSB/SOA. JMS queues provide for inter-application communication. Patch lifecycle of OSB/SOA/JMS are no longer lock stepped. JMS may be kept running independently of other domains allowing applications to insert messages fro later consumption by SOA/OSB. OSB may be kept running independent of other domains, allowing service virtualization to continue independent of other domains availability. All domains use same OWSM policy store (MDS-WSM). Supports large numbers of deployed composites in multiple domains. Single URL for Human Workflow end users. Single URL for BAM end users. Drawbacks Multiple domains to manage and configure. Multiple Admin servers (single view requires use of Grid Control) Multiple Admin servers/WSM clusters waste resources. Additional homes needed to enjoy benefits of separate patching. Cross domain trust needs setting up to simplify cross domain interactions. Human Workflow needs to be specially configured to point to shared services domain. Summary The alternatives in this blog allow for patching to have different impacts, depending on the model chosen.  Each organization must decide the tradeoffs for itself.  One extreme is to go for the shared services model and have one domain per SOA application.  This requires a lot of administration of the multiple domains.  The other extreme is to have a single super domain.  This makes the entire enterprise susceptible to an outage at the same time due to patching or other domain level changes.  Hopefully this blog will help your organization choose the right model for you.

    Read the article

  • Proxy cache zone static is unknown

    - by AnApprentice
    I'm working to setup a reverse proxy cache. In nginx.conf I added the following: location /blog { # Reverse Proxy # Cache the Blog Pages from Heroku proxy_cache STATIC; proxy_cache_valid 200 10m; proxy_cache_valid 404 1m; proxy_cache_use_stale error timeout invalid_header updating http_500 http_502 http_503 http_504; rewrite ^/blog$ /; rewrite ^/blog/(.*)$ /$1; proxy_pass http://whispering-retreat-1.herokuapp.com; break; } However when trying to restart nginx I received the following error: $ /opt/nginx/sbin/nginx -s stop nginx: [emerg] "proxy_cache" zone "STATIC" is unknown in /opt/nginx/conf/nginx.conf:182 Any ideas what's the problem is with using STATIC? I just want to cache the blog pages so it doesn't hit heroku every time which is horribly slow. Thanks

    Read the article

  • which performance counters mainly matter for windows server performance?

    - by Karl Cassar
    We have a website which is sometimes performing slowly, and / or completely hangs. I have setted up temporarily the default system performance data collector in Performance Monitor, to see if this can shed some light. However, the default Data Collector set collects a huge amount of counters, as well as generates huge logs files. Just 8 hours of data resulted in 4GB of data. Which performance counters matter the most, when judging server load? Also, is it a performance concern if one leaves such data-collectors running indefinitely? Obviously, I will not know when the server will experience slow performance, so I need the logs there so that I can check them out. Any other specific guidelines on monitoring server performance would be greatly appreciated. OS is a Windows Server 2008 R2 (Web Edition).

    Read the article

  • Home networking problem between power line communication and Ethernet

    - by pixeline
    My network runs through the electrical wiring of the house and is organised as such: Groundfloor: an ADSL+network switch, using DHCP (address : 172.19.3.1) (Mac) PCs connected via an electrical adapter (model: D-Link DHP-200) (1 per PC) First Floor: 1 switch (8 ports) connected via an electrical adapter (model: D-Link DHP-200) (address unknown) 2 Mac PCs connected (via RJ45 network wires) to that router using DHCP The Problem On the first floor, file tranfers between PCs are fast and perfect. But if I try to transfer files from or to a computer on the ground floor, the speed is slow and eventually the transfer dies out. The Question So I suspect the 1st floor switch is creating some kind of barrier (firewall?) preventing external PCs from accessing the PCs it is connected to? Am I right and if so, how could I disable that barrier?

    Read the article

  • High Tq values for HAProxy

    - by Will
    I just took over administration of a new environment. A known issue is that the environment is known for high response times (20+ seconds), so I figured I'd turn on haproxy logging and see what is going on. I figured I'd see slow load times in the app servers, but I'm actually seeing high Tq values in HAProxy. The HAProxy is on EC2 and is NOT behind ELB. Sep 5 14:22:00 haproxy-apps01 haproxy[24695]: 76.14.153.221:3371 [05/Sep/2012:14:21:49.780] http-in default_apps/fe04-c 10936/0/0/55/10991 200 488 - - ---- 111/111/0/1/0 0/0 "GET /event_times/next?callback=jQuery170189312373075111_1346854917562&_=1346854918453 HTTP/1.1" As you can see, this one has a Tq of about 10 seconds. Not all the Tq's are high (1+ seconds), but a good percentage of them are (approx 35%). Normally when I see this behavior, I'd expect there to be network issues, but this is an incredibly high percentage of visitors to be having an issue like this, so I'm wondering if anybody has seen this or have any hints on diagnosing if the issue could possibly be on this box?

    Read the article

  • I need to get VMWare Server running inside of a VMWare ESXi virtual machine

    - by Josh Moore
    Yes, I know running a virtual machine inside of a virtual machine is a bad idea. Yes, I know it will be very slow. However, our production system required VMs in VMWare server and I do not want to setup a real server for each of our developers for testing. I would like to be able to setup all of the VMWare servers (that mimic our production environment) on one ESXi server. I have found as much info as I can about this topic and I have tried what was suggested here and here. I have not been able to get any of these suggestions to work, I still get the VM cannot run inside of a VM error. If there are any other suggestions that anybody else have that would be great thanks.

    Read the article

  • NHibernate which cache to use for WinForms application

    - by chiccodoro
    I have a C# WinForms application with a database backend (oracle) and use NHibernate for O/R mapping. I would like to reduce communication to the database as much as possible since the network in here is quite slow, so I read about second level caching. I found this quite good introduction, which lists the following available cache implementations. I'm wondering which implementation I should use for my application. The caching should be simple, it should not significantly slow down the first occurrence of a query, and it should not take much memory to load the implementing assemblies. (With NHibernate and Castle, the application already takes up to 80 MB of RAM!) Velocity: uses Microsoft Velocity which is a highly scalable in-memory application cache for all kinds of data. Prevalence: uses Bamboo.Prevalence as the cache provider. Bamboo.Prevalence is a .NET implementation of the object prevalence concept brought to life by Klaus Wuestefeld in Prevayler. Bamboo.Prevalence provides transparent object persistence to deterministic systems targeting the CLR. It offers persistent caching for smart client applications. SysCache: Uses System.Web.Caching.Cache as the cache provider. This means that you can rely on ASP.NET caching feature to understand how it works. SysCache2: Similar to NHibernate.Caches.SysCache, uses ASP.NET cache. This provider also supports SQL dependency-based expiration, meaning that it is possible to configure certain cache regions to automatically expire when the relevant data in the database changes. MemCache: uses memcached; memcached is a high-performance, distributed memory object caching system, generic in nature, but intended for use in speeding up dynamic web applications by alleviating database load. Basically a distributed hash table. SharedCache: high-performance, distributed and replicated memory object caching system. See here and here for more info My considerations so far were: Velocity seems quite heavyweight and overkill (the files totally take 467 KB of disk space, haven't measured the RAM it takes so far because I didn't manage to make it run, see below) Prevalence, at least in my first attempt, slowed down my query from ~0.5 secs to ~5 secs, and caching didn't work (see below) SysCache seems to be for ASP.NET, not for winforms. MemCache and SharedCache seem to be for distributed scenarios. Which one would you suggest me to use? There would also be a built-in implementation, which of course is very lightweight, but the referenced article tells me that I "(...) should never use this cache provider for production code but only for testing." Besides the question which fits best into my situation I also faced problems with applying them: Velocity complained that "dcacheClient" tag not specified in the application configuration file. Specify valid tag in configuration file," although I created an app.config file for the assembly and pasted the example from this article. Prevalence, as mentioned above, heavily slowed down my first query, and the next time the exact same query was executed, another select was sent to the database. Maybe I should "externalize" this topic into another post. I will do that if someone tells me it is absolutely unusual that a query is slowed down so much and he needs further details to help me.

    Read the article

  • OpenCV : How to display webcam capture in windows form application?

    - by sneixum
    generally we display webcam or video motion in opencv windows with : CvCapture* capture = cvCreateCameraCapture(0); cvNamedWindow( "title", CV_WINDOW_AUTOSIZE ); cvMoveWindow("title",x,y); while(1) { frame = cvQueryFrame( capture ); if( !frame ) { break; } cvShowImage( "title", frame ); char c = cvWaitKey(33); if( c == 27 ) { break; } } i tried to use pictureBox that is successful to display image in windows form with this : pictureBox1-Image = gcnew System::Drawing::Bitmap( image-width,image-height,image-widthStep,System::Drawing::Imaging::PixelFormat::Undefined, ( System::IntPtr ) image- imageData); but when im trying to display captured image from video it wont works, here is the source : CvCapture* capture = cvCreateCameraCapture(0); while(1) { frame = cvQueryFrame( capture ); if( !frame ) { break; } pictureBox1->Image = gcnew System::Drawing::Bitmap( frame->width,frame->height,frame->widthStep,System::Drawing::Imaging::PixelFormat::Undefined, ( System::IntPtr ) frame-> imageData); char c = cvWaitKey(33); if( c == 27 ) { break; } } is there anyway to use windows form instead opencv windows to show video or webcam? or is there something wrong with my code? thanks for your help.. :)

    Read the article

  • Virus that tries to brute force attack Active Directory users (in alphabetical order)?

    - by Nate Pinchot
    Users started complaining about slow network speed so I fired up Wireshark. Did some checking and found many PCs sending packets similar to the following: (screenshot) http://imgur.com/45VlI.png I blurred out the text for the username, computer name and domain name (since it matches the internet domain name). Computers are spamming the Active Directory servers trying to brute force hack passwords. It will start with Administrator and go down the list of users in alphabetical order. Physically going to the PC finds no one anywhere near it and this behavior is spread across the network so it appears to be a virus of some sort. Scanning computers which have been caught spamming the server with Malwarebytes, Super Antispyware and BitDefender (this is the antivirus the client has) yields no results. This is an enterprise network with about 2500 PCs so doing a rebuild is not a favorable option. My next step is to contact BitDefender to see what help they can provide. Has anybody seen anything like this or have any ideas what it could possibly be?

    Read the article

  • How to install a Canon iRunner 210s

    - by Ssvarc
    A client has a Canon iRunner210S and is complaining about slow print speeds. I've searched for a install manual online but came up empty. A call to Canon technical referred me to their dealer network for service, as as informing me that there isn't a manual available on their website. Anyone know how to install these and/or have a link to a manual? The current setup has the printers on a LAN Manager printer port instead of on straight IP ports. Is this normal for this printer? And what exactly are Lan Manager ports (based on my research, they appear to be a way to authenticate a connection)?

    Read the article

  • Looking for a manual/how-to for installing a Canon iRunner 210s network printer

    - by Ssvarc
    A client has a Canon iRunner210S and is complaining about slow print speeds. I've searched for a install manual online but came up empty. A call to Canon technical referred me to their dealer network for service, as as informing me that there isn't a manual available on their website. Anyone know how to install these and/or have a link to a manual? The current setup has the printers on a LAN Manager printer port instead of on straight IP ports. Is this normal for this printer? And what exactly are Lan Manager ports (based on my research, they appear to be a way to authenticate a connection)?

    Read the article

  • Linux: setting up an elite/high-anonimity Web proxy on a dedicated server

    - by YellowSquirrel
    I'm renting a dedicated server which I'd like to use to "surf the Web": basically I want to always surf the Web from the same static IP (the one of my dedicated server). I can do it by running Xvnc/FreeNX on the dedicated server, but this is kinda slow and clumsy (I tried it). What are the steps needed to install an "elite/high-anonimity" Web proxy on a dedicated (Debian) Linux server knowing that my two requirements are: I'm the only person that needs access to the proxy all I want is that my broadband (dynamic) IP is completely hidden (I want to always surf from my dedicated server's IP). Note that using the static IP people can find my domains and my real name and I'm perfectly fine with that (actually it is what I want). What I don't want is people knowing from which dynamic IP (broadband) I'm connecting. What are the steps needed to do that? (basically I don't care about "anonimity", what I want is to appear to surf from a static IP and I think I need what is called an "elite" Web proxy to do that, but I'm not sure) Technical infos and sample configuration most welcome :)

    Read the article

  • Magento Community - Hosting :: Need Advice which sharing hosting will run magento fast

    - by user43353
    Hi, Need Advice which sharing hosting will run Magento Community fast or some other not expensive solution. This website will not have a lot of users, I only need that it will run fast for 100-20 users in same time. The problem with magento is database design that make this system very slow , also other staff not the best. I had hostmonster.com and justhost.com for previous website but it wasn't fast enough for single user that not located in USA (my customer areas: Asia, Africa). each action that involve database takes a lot of time. Thanks

    Read the article

  • Experience with MooseFS?

    - by brown.2179
    Anyone have any experience using MooseFS? I want an easy distributed storage platform to store static data archive of about 10 TB and serve it to 20-40 nodes. Also I want to be able to add storage as the archive grows without having to rebuild the filesystem. I don't care if it's a bit slow. I just want it to be simple and stable. Basically from what I can see for OS X it's between MooseFS and Gluster. Any other suggestions?

    Read the article

  • How to adjust and combine multiple lower quality photos into one better using FOSS?

    - by Vi
    I have multiple noisy photos (caputed without tripod) that needs to be adjusted (moved/rotated) and averaged. How it's better to do it in Linux with FOSS console-based programs? Current way is something like: mplayer mf://*.JPG -vo yuv4mpeg:file=qqq.yuv transcode -i qqq.yuv -y null -J stabilize=maxshift=500:fieldsize=100:fieldnum=6:stepsize=50:shakiness=10 transcode -i qqq.yuv -J transform=smoothing=100000:sharpen=0:optzoom=0 -y raw -o www.yuv mplayer www.yuv -vo pnm gm convert -average 0*.ppm q.ppm i.e.: Convert photos to video Apply Transcode's "Stabilize" filter Convert the video back to images Average the images. It works, but bad: photos still not perfectly adjusted and the whole sequence is very slow. What is better way of doing it?

    Read the article

  • Linux Kernel Messages: ata1.00: status: { DRDY ERR }

    - by PM
    I am receiving a lot of these messages. Is my HD going to die tomorrow morning? ata1: link is slow to respond, please be patient (ready=0) ata1: device not ready (errno=-16), forcing hardreset ata1: soft resetting link ata1: clearing spurious IRQ ata1: clearing spurious IRQ ata1: clearing spurious IRQ ata1.00: configured for UDMA/33 ata1: EH complete ata1.00: qc timeout (cmd 0xa0) ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x6 frozen ata1.00: cmd a0/00:00:00:00:00/00:00:00:00:00/a0 tag 0 cdb 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 res 51/20:03:00:00:00/00:00:00:00:00/a0 Emask 0x5 (timeout)

    Read the article

  • Simple animation using C#/Windows Forms

    - by clintp
    I need to knock out a quick animation in C#/Windows Forms for a Halloween display. Just some 2D shapes moving about on a solid background. Since this is just a quick one-off project I really don't want to install and learn an entire new set of tools for this. (DirectX dev kits, Silverlight, Flash, etc..) I also have to install this on multiple computers so anything beyond the basic .Net framework (2.0) would be a pain in the arse. For tools I've got VS2k8, 25 years of development experience, a wheelbarrow, holocaust cloak, and about 2 days to knock this out. I haven't done animation since using assembler on my Atari 130XE (hooray for page flipping and player/missile graphics!) Advice? Here's some of the things I'd like to know: I can draw on any empty widget (like a panel) by fiddling with it's OnPaint handler, right? That's how I'd draw a custom widget. Is there a better technique than this? Is there a page-flipping technique for this kind of thing in Windows Forms? I'm not looking for a high frame rate, just as little flicker/drawing as necessary. Thanks. Post Mortem Edit ... "a couple of coding days later" Well, the project is done. The links below came in handy although a couple of them were 404. (I wish SO would allow more than one reply to be marked "correct"). The biggest problem I had to overcome was flickering, and a persistent bug when I tried to draw on the form directly. Using the OnPaint event for the Form: bad idea. I never got that to work; lots of mysterious errors (stack overflows, or ArgumentNullExceptions). I wound up using a panel sized to fill the form and that worked fine. Using the OnPaint method is slow anyway. Somewhere online I read that building the PaintEventArgs was slow, and they weren't kidding. Lots of flickering went away when I abandoned this. Skip the OnPaint/Invalidate() and just paint it yourself. Setting all of the "double buffering" options on the form still left some flicker that had to be fixed. (And I found conflicting docs that said "set them on the control" and "set them on the form". Well controls don't have a .SetStyle() method.) I haven't tested without them, so they might be doing something (this is the form): this.SetStyle(ControlStyles.UserPaint, true); this.SetStyle(ControlStyles.OptimizedDoubleBuffer, true); this.SetStyle(ControlStyles.AllPaintingInWmPaint, true); So the workhorse of the code wound up looking like (pf is the panel control): void PaintPlayField() { Bitmap bufl = new Bitmap(pf.Width, pf.Height); using (Graphics g = Graphics.FromImage(bufl)) { g.FillRectangle(Brushes.Black, new Rectangle(0, 0, pf.Width, pf.Height)); DrawItems(g); DrawMoreItems(g); pf.CreateGraphics().DrawImageUnscaled(bufl, 0, 0); } } And I just called PaintPlayField from the inside of my Timer loop. No flicker at all.

    Read the article

  • RAIDZ vs RAID1+0

    - by Hiro2k
    Hi guys I just got 4 SSDs for my FreeNAS box. This server is only used to serve a single iSCSI extent to my Citrix XenServer pool and was wondering if I should setup them up in a RAIDZ or a RAID 1+0 configuration. This isn't used for anything in production, just for my test lab so I'm not sure which one is going to be better in this scenario. Will I see a major difference in speed or reliability? Currently the server has three 500GB Western Digital Blue drives and it's dog slow when I deploy a new version of our software on it, hence the upgrade.

    Read the article

  • Restoring Time Machine from two Macs onto one (new) mac

    - by Dan
    My parents used to have two Macs...a "iLamp-style" iMac for my Dad, and an iBook G4 for my Mom. A while back, I had setup the iMac to have an external Firewire Hard Drive for a Time Machine Volume, and backed up both the iMac and iBook to that drive. Recently, the iBook died and the iMac was really slow to work with. So my parents decided to replace the iBook with an iPad, and also purchased a Mac Mini. I need to help my parents get their data from their two computers (backed up by Time Machine) onto the same machine. Pretty much everything is identical between the two systems (same apps, etc), however, they both have individual email accounts and photos that they want to retain. Is it possible to do two Time Machine restores onto one computer?

    Read the article

< Previous Page | 134 135 136 137 138 139 140 141 142 143 144 145  | Next Page >