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  • Emailing Interviewer after interview regarding technical solution

    - by Raghav Shankar
    I had an interview yesterday where I was given a programming problem and I was asked to figure the optimal solution for it. I gave a solution that worked in linear time, but used 2 loops (not inner loops). At the end of the interview, the interviewer saw I was interested in solving the problem, so he said the optimal solution uses only one loop and has linear complexity and at the end of the interview I had asked for his card and he gave one to me. I think I might have figured out a solution and I was wondering if it's alright to email the recruiter thanking him for his time and also mentioning about the solution I had figured out?

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  • Some mail details about Orange Mauritius

    Being an internet service provider is not easy after all for a lot of companies. Luckily, there are quite some good international operators in this world. For example Orange Mauritius aka Mauritius Telecom aka Wanadoo(?) aka MyT here in Mauritius. The local circumstances give them a quasi-monopol position on fixed lines for telephony and therefore cable-based DSL internet connectivity. So far, not bad but as usual... the details. Just for the records, I am only using the services of Orange for mobile but friends and customers are bound, eh stuck, with other services of Orange Mauritius. And usually, being the IT guy, they get in touch with me to complain about problems or to ask questions on either their ADSL / MyT connection, mail services or whatever. Most of those issues are user-related and easily to solve by tweaking the configuration of their computer a little bit but sometimes it's getting weird. Using Orange ADSL... somewhere else Now, let's imagine we are an Orange ADSL customer for ages and we are using their mail services with our very own mail address like "[email protected]". We configured our mail client like Thunderbird, Outlook Express, Outlook or Windows Mail as publicly described, and we are able to receive and send emails like a champion. No problems at all, the world is green. Did I mention that we have a laptop? Ok, let's take our movable piece of information technology and visit a friend here on the island. Not surprising, he is also customer of Orange, so we can read and answer emails. But Orange is not the online internet service provider and one day, we happen to hang out with someone that uses Emtel via WiMAX or UMTS.. And the fun starts... We can still receive and read emails from our Orange mail account and the IT world is still bright but try to send mails to someone outside the domain "@intnet.mu" or "@orange.mu". Your mail client will deny sending mail with SMTP message 5.1.0 "blah not allowed". First guess, there is problem with the mail client, maybe magically the configuration changed over-night. But no it is still working at home... So, there is for sure a problem with the guy's internet connection. At least, it is his fault not to have Orange internet services, so it can not work properly... The Orange Mail FAQ After some more frustation we finally checkout the Orange Mail FAQ to see whether this (obviously?) common problem has been described already. Sorry, but those FAQ entries are even more confusing as it is not really clear how to handle this scenario. Best of all is that most of the entries are still refering to use servers of the domain "intnet.mu". I mean Orange will disable those systems in favour of the domain "orange.mu" in the near future and does not amend their FAQs. Come on, guys! Ok, settings for POP3 are there. Hm, what about the secure version POP3S? No signs at all... Even changing your mail client to use password encryption with STARTTLS is not allowed at all. Use "bow.intnet.mu" for incoming mail... Ahhh, pretty obvious host name. I mean, at least something like pop.intnet.mu or pop3.intnet.mu would have been more accurate. Funny of all, the hostname "pop.orange.mu" is accessible to receive your mail account. Alright, checking SMTP options for authentication or other like POP-before-SMTP or whatever well-known and established mechanism to send emails are described. I guess that spotting a whale or shark in Mauritian waters would be easier. Trial and error on SMTP settings reveal that neither STARTTLS or any other connection / password encryption is available. Using SSL/TLS on SMTP only reveals that there is no service answering your request. Calling customer service So, we have to bite into the bitter apple and get in touch with Orange customer service and complain/explain them our case and ask for advice. After some hiccups, we finally manage to get hold of someone competent in mail services and we receive the golden spoon of mail configuration made by Orange Mauritius: SMTP hostname: smtpauth.intnet.mu And the world of IT is surprisingly green again. Customer satisfaction? Dear Orange Mauritius, what's the problem with this information? Are you scared of mail spammer? Why isn't there any case in your FAQs? Ok, talking about your FAQs - simply said: they are badly outdated! Configure your mail client to use server name based in the domain intnet.mu but specify your account username with orange.mu as domain part. Although, that there are servers available on the domain orange.mu after all. So, why don't you provide current information like this: POP3 server name: pop.orange.muSMTP server name: smtp.orange.muSMTP authenticated: smtpauth.orange.mu It's not difficult, is it? In my humble opinion not really and you would provide clean, consistent and up-to-date information for your customers. This would produce less frustation and so less traffic on your customer service lines. Which after all, would improve the total user experience and satisfaction level on both sides. Without knowing these facts. Now, imagine you would take your laptop abroad and have to use other internet service providers to be able to be online... Calling your customer service would be unnecessary expensive!

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  • WPF: Reloading app parts to handle persistence as well as memory management.

    - by Ingó Vals
    I created a app using Microsoft's WPF. It mostly handles data reading and input as well as associating relations between data within specific parameters. As a total beginner I made some bad design decision ( not so much decisions as using the first thing I got to work ) but now understanding WPF better I'm getting the urge to refactor my code with better design principles. I had several problems but I guess each deserves it's own question for clarity. Here I'm asking for proper ways to handle the data itself. In the original I wrapped each row in a object when fetched from database ( using LINQ to SQL ) somewhat like Active Record just not active or persistence (each app instance had it's own data handling part). The app has subunits handling different aspects. However as it was setup it loaded everything when started. This creates several problems, for example often it wouldn't be neccesary to load a part unless we were specifically going to work with that part so I wan't some form of lazy loading. Also there was problem with inner persistance because you might create a new object/row in one aspect and perhaps set relation between it and different object but the new object wouldn't appear until the program was restarted. Persistance between instances of the app won't be huge problem because of the small amount of people using the program. While I could solve this now using dirty tricks I would rather refactor the program and do it elegantly, Now the question is how. I know there are several ways and a few come to mind: 1) Each aspect of the program is it's own UserControl that get's reloaded/instanced everytime you navigate to it. This ensures you only load up the data you need and you get some persistancy. DB server located on same LAN and tables are small so that shouldn't be a big problem. Minor drawback is that you would have to remember the state of each aspect so you wouldn't always start at beginners square. 2) Having a ViewModel type object at the base level of the app with lazy loading and some kind of timeout. I would then propegate this object down the visual tree to ensure every aspect is getting it's data from the same instance 3) Semi active record data layer with static load methods. 4) Some other idea What in your opinion is the most practical way in WPF, what does MVVM assume?

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  • HighPoint RocketRAID 62x Controller

    - by TeXnewbie
    I have the subject card recently installed in Ubuntu 12.04.1 LTS (GNU/Linux 3.2.0-31-generic x86_64). See partial lspci -vv listing below (complete listing played havoc with pre tags): 03:00.0 RAID bus controller: HighPoint Technologies, Inc. Device 0622 (rev 01) Subsystem: HighPoint Technologies, Inc. Device 0001 Control: I/O+ Mem+ BusMaster+ SpecCycle- MemWINV- VGASnoop- ParErr- Stepping- SERR- FastB2B- DisINTx- Latency: 0, Cache Line Size: 32 bytes Interrupt: pin A routed to IRQ 11 Region 0: I/O ports at 9c00 [size=8] Region 1: I/O ports at 9800 [size=4] Region 2: I/O ports at 9400 [size=8] Region 3: I/O ports at 9000 [size=4] Region 4: I/O ports at 8c00 [size=16] Region 5: Memory at fdbff000 (32-bit, non-prefetchable) [size=2K] Expansion ROM at fdbe0000 [disabled] [size=64K] Capabilities: I followed instructions I found at https://help.ubuntu.com/community/RocketRaid to compile the drivers for it, and although performing the process described there seemed to work fine with no noticeable errors, when I rebooted after performing that procedure I could not boot. During dkms steps, I noticed messages indicating that (If next boot fails, revert to initrd.img-3.2.0-31-generic.old-dkms image) update-initramfs................ so I booted using a Ubuntu 12.10 LiveDVD and reverted to the old-dkms initrd.img as suggested above, but this failed to repair the boot problem. Ultimately, I used https://help.ubuntu.com/community/Boot-Repair in Ubuntu-Secure-Remix to fix the boot problem and was able to boot normally again, but now with the newly generated initrd.img in place again (which now boots normally), when I modprobe the rr62x kernel module, I immediately get a hard crash with messages to console about a kernel paging request that seems to have caused the problem. I've tried on multiple occasions now to use the newly built kernel module so as to allow me to use an eSATA port multiplier plugged into the card, but to no avail. Any suggestions on fixes or workarounds (I've read that some of the HighPoint cards (2720SGL) seem to work as a host bus adapter and thus may not need a custom driver, but that seems not to be the case for mine) would be most appreciated. My goal is to use the card as described here and with software RAID mdadm utilities. If necessary, I can hand-copy the console messages after the hard crash into a follow-up message, but I obviously can't do a cut/paste. I'll gladly provide any other details that are needed, but not sure what those would be at this point, so I'll refrain from adding other details for now. Thanks in advance for any help.

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  • Dell Inspiron touchpad not working

    - by Bobby
    I own a Dell Inspiron on which I installed 12.04 on. Everything was working great up until a couple of weeks ago when the Touchpad stopped working. It doesn't show up in mouse/touchpad settings either. I was wondering if anyone has had the same problem with 12.04 and was able to fix it. I am a noob when it comes to computer code and stuff like that, so please try to keep the answer noob proof. Also, does anyone know if the guys behind Ubuntu will have an update to fix this problem?

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  • 3D Studio Max biped restrictions?

    - by meds
    I have a stock biped character in 3D studio max which has a jump animation. The problem I have with the jump animation is that there is actual y offset happening inside it which makes it awkward to play while the character is jumping since it's not only jumping in the game world but the jump animation is adding its own height offset. I'm tryuing to remove the jump animations height offset, so far I've found the root node and deleted all its key frames which has helped a bit. The problem I'm having now is that the character still has some height offset and if I try to lower it it has a fake 'ground' that isn't at 0 and the limbs sort of bend on the imaginary floor, si there a way to remove this restriction just for the jump animation? Here's what I mean: http://i.imgur.com/qoWIR.png Any idea for a fix? I'm using Unity 3D if that opens any other possibilities...

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  • Sales Manager: "Why is time-estimation so complex?"

    - by Tim
    A few days ago a sales manager asked me that question. But at this moment I didn't know a answer which he can understand. He isn't a programmer! At the moment I work on a product which is over 8 years old. Nobody thought about architecture or evolvability. I have a swamp of code in front of me every day which is not tested. Because of that, time estimates are very difficult for me. How I can describe that problem to an salesman? Not only my swamp-code-problem, but general!

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  • Facebook and Gmail stop working after 10 minutes

    - by Julia
    I have problem with facebook and gmail only: It works fine and lets me log in, view photos and videos, read new messages, etc. But after 5-10 minuets it doesn't load at all This webpage is not available. The webpage at http://www.facebook.com/ might be temporarily down or it may have moved permanently to a new web address. More information on this error Below is the original error message Error 101 (net::ERR_CONNECTION_RESET): Unknown error After deleting cookies this problem disappears for 5-10 minuets, then I get the same error. It happens with Google Chrome and Firefox. Ping works fine. I have checked System-Preferences-Network Proxy it sets on Default - "Direct Internet Connection". Then I have run test (chrome://net-internals/#tests) and got some FAIL results Use system proxy settings Disable IPv6 host resolving Probe for IPv6 host resolving IPv6 is disabled.

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  • Count unique visitors by group of visited places

    - by Mathieu
    I'm facing the problem of counting the unique visitors of groups of places. Here is the situation: I have visitors that can visit places. For example, that can be internet users visiting web pages, or customers going to restaurants. A visitor can visit as much places as he wishes, and a place can be visited by several visitors. A visitor can come to the same place several times. The places belong to groups. A group can obviously contain several places, and places can belong to several groups. Given that, for each visitor, we can have a list of visited places, how can I have the number of unique visitors per group of places? Example: I have visitors A, B, C and D; and I have places x, y and z. I have these visiting lists: [ A -> [x,x,y,x], B -> [], C -> [z,z], D -> [y,x,x,z] ] Having these number of unique visitors per place is quite easy: [ x -> 2, // A and D visited x y -> 2, // A and D visited y z -> 2 // C and D visited z ] But if I have these groups: [ G1 -> [x,y,z], G2 -> [x,z], G3 -> [x,y] ] How can I have this information? [ G1 -> 3, // A, C and D visited x or y or z G2 -> 3, // A, C and D visited x or z G3 -> 2 // A and D visited x or y ] Additional notes : There are so many places that it is not possible to store information about every possible group; It's not a problem if approximation are made. I don't need 100% precision. Having a fast algorithm that tells me that there were 12345 visits in a group instead of 12543 is better than a slow algorithm telling the exact number. Let's say there can be ~5% deviation. Is there an algorithm or class of algorithms that addresses this type of problem?

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  • Detecting if an object is following a path

    - by justin.m.chase
    I am attempting to take GPS data and track it on a map and see if it follows a given path. I have the path as a set of points and the GPS data streams in as a similar set of points. I am attempting to track the progression of the current position across the path and I am wondering if there are any well known algorithms for this. I have come up with my own that works ok but it is a complex enough problem that I would like to minimize the amount of re-inventing of the wheel that I do. What approach or algorithm would you recommend taking for this problem?

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  • Seek Steering Behavior with Target Direction for Group of Fighters

    - by SebastianStehle
    I am implementing steering algorithms with group management for spaceships (fighters). I select a leader and assign the target positions for the other spaceships based on the target position of the leader and an offset. This works well. But when my spaceships arrive they all have a different direction. I want them to keep to look in the same direction (target - start). I also want to combine this behavior with a minimum turning radius that is based on the speed. The only idea I have is to calculate a path for each spaceship with an point before the target position, so the ships have some time left to turn into the right position. But I dont know if this is a good idea. I guess there will be a lot of rare cases where this can cause a problem. So the question is, if anybody knows how to solve this problem and has some (simple code) or pseudocode for me or at least some good explanation.

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  • How can I simulate objects floating on water without a physics engine?

    - by user1075940
    In my game the water movement is done in a shader using Gerstner equations. The water movement looks realistic enough for a school project but I encounter serious problem when I wanted to do sailing on waves (similar to this). I managed to do collision with land by calculating quad's vertices and normals beneath ship, however same method can not be applied to water because XZ are displaced and Y is calculated in a shader :( How to approach this problem ? Is it possible to retrieve transformed grid from shader? Unfortunately no external physics libraries can be used.

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  • How can I prevent or diminish Nautilus freezing problems?

    - by Karthick Bala
    Hi, After upgrading the Ubuntu to 10.04 my Nautilus file manager gives lot of problem. Nautilus freezes after few minutes of start. I tried with Thunar, but I did not like that. Now I have Dolphin too, when Nautilus goes problem, then I start work with Dolphin. I do not like this. I want to work on Nautilus or equivalent one. I work with lot of images using GIMP and Inkscape. I tried many things including reinstalled the OS for 6 time in 4 months. I cannot leave Ubuntu, but I am limbing. Some body help me to fix it. Thanks in Advance.

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  • Is there a better approach in migrating SIT SVN to UAT SVN?

    - by huahsin68
    In web development, given a same piece of source code, and being deploy to SIT (system integration testing) SVN/WAS and UAT (user acceptance testing) SVN/WAS. Please take note that I am using Jenkins to build everything. I have already ensured the transition from SIT SVN to UAT SVN are sync by doing manual diff on the 2 directory. Usually I will ensure the SIT WAS is working fine then only deploy to UAT WAS. But now there is a problem show up in UAT WAS and it is working fine in SIT WAS. I am suspecting there is a migration fault happened between SIT SVN to UAT SVN. In such a given scenario, is there a better approach to handle this problem?

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  • Installing windows after ubuntu is installed (need to create ntfs partition too)

    - by Brent Roose
    I prefer Ubuntu to work on, but for some applications for school, I need windows. I've done some research and have a few problems: I only have one hard drive which is formatted as ext4, not ntfs. Many people say I have to use Gparted to create an ntfs partition to install windows on, the only problem is that I need to unmount my drive to do this, which isn't possible I think because I only have one. I thought about mounting my HDD as a slave on a windows laptop but I don't manage to partition it with windows partition manager, so I think I need some kind of tool. which one? next problem I'll probably have is that I won't be able to boot ubuntu after installing windows because grub will be removed from my MBR. are there any good guides around here? I've used some kind of tool before, but it crashed my whole HDD so I had to fully format it.

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  • Creating practically solvable 15 puzzle inputs

    - by Ashwin
    I am now developing a 15 puzzle game. I know the method to detect unsolvable puzzles. But unlike 8-puzzle, solution for 15-puzzle takes quite long time for some input states and can be solved within 5 seconds some other set of input states. Now the problem is that I cannot give the user(the player), a problem for which the solution takes more than 10 seconds(if he/she chooses to see the solution). So what I want is that when I initially shuffle the puzzle, I want to only present those puzzles which can be solved within 10 seconds. There must be some way to determine the hardness of the puzzle. I tried searching the net but could not find it. Does anyone know a way of determining the hardness of a puzzle? NOTE : I am using A* algorithm to find out the solution on a computer with 3GB RAM and 2.27GHZ processor.

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  • Can only run firefox 8.0 in safe mode [closed]

    - by Max Popp
    This is a recent problem but I have no idea what caused it: I can only run firefox in safe mode. Any other mode, I get a completely khaki, unresponsive screen, that I have to forcibly terminate. I have uninstalled firefox, and then re-installed it via synaptic. That didn't seem to work. The problem occurs in all the four user accounts I have defined in the ubuntu. I am running an ubuntu 11.10, amd64. My firefox is version 8.0.

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  • Apple Developer Enterprise Program?

    - by Gnial0id
    I'm building an iOS application for a client (not an enterprise but non-profit association with under than 500 employess), distributed in a free version and a "paid" one. The free version will be available with iTunes/AppStore, no problem with that. But about the paid one... the distribution my client wants is different. They want to distribute it to their clients as a bonus in their subscription, and so, to control this distribution. The first answer would be "iOS Developer Enterprise Program", but it's not an enterprise and have less than 500 employees. Will the fact that my client will distribute the app' with a subscription be a problem ? I spend a lot of time to read documentation, but it is not very clear. I'm a bit lost, I admit it. Any help would grateful.

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  • Flash doesn't work any more on 10.04

    - by Béné
    I have a very strange problem with flash on my 10.04 system. (An update to 12.04 is not an option, because the system is just too old and slow.) After a recent update flash has just stopped working altogether. Youtube just shows a white square, vimeo a black one. After a 10.04 reinstall the problem stays the same. Not even chrome displays flash content, just a message that shockwave flash could not be loaded. 'ubuntu-restricted-extras' 'flashplugin-nonfree' and 'flashplugin-installer' are all installed in version 11.2.202.238ubuntu0.10.04.1.

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  • Monitor blinking

    - by Shark
    Hi I have Ubuntu 10.04, my laptop is ASUS k50ij, intel duo t3000, 2gb ram, 320 HDD, intel gma 4500M video card. My problem is that a couple days ago my monitor had start blinking for a few seconds. Then it stops and begins the same behaviour let's say in next 2 hours. What am i missing here? Another funny problem is that when i give more or less brightness to monitor the pop up window shows and giving "Power information: Laptop battery is charged". When my brightness is lower the blinking increases and vice versa. thx for help

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  • Missing Indexes DMV Report, 3 billion Impact!

    - by Tara Kizer
    We’ve been having some major performance issues with one of the applications that I support.  The database is on SQL Server 2005 and is about 150GB in size.  We’ve identified a couple of issues already on the database side.  The first issue is that some query (or maybe several queries) is getting a bad execution plan at some point in time during the day.  When it occurs, database performance comes to a grinding halt.  We know it’s a bad execution plan as running DBCC FREEPROCCACHE immediately resolves the problem system-wide.  As we have not yet identified the problematic query, we’ve put a temporary solution in place that frees the procedure cache on an hourly basis via a SQL Agent job.  This is not ideal, but it is getting us through the day without a major problem.  We are actively working on identifying the problematic query and hope to disable the SQL Agent job soon. Earlier this week, we had a major slowdown for one of the processes of this application.  I was unable to find any database performance issues, but I continued to investigate it.  One of things that I typically do when investigating database performance issues is run the “Missing Indexes DMV Report” (that’s what I call it at least).  When analyzing the output of that report, I immediately dismiss anything under 1 million “Impact” as I want to target the “low-hanging fruit” initially.  When I ran the report earlier this week, I was shocked to find a suggested index with an impact of over 3 billion! Do I win a prize for the highest impact?  Has anyone seen a value higher than mine?  My exact value was 3154284120.67765. The performance issue from earlier this week ended up being an application problem, but it also brought to light a much needed index.  I had previously seen this index come up in that report but always with a much lower impact.  I had never considered it as the index’s selectivity is very low.  It’s a composite index with three columns.  The first column is not selective, the first two columns are not selective, and the three columns together are not selective.  In fact, no matter how I order it, the index will not be selective at all.  I briefly discussed this with Kimberly Tripp, and she said that this was okay for covering indexes.  Selectivity is irrelevant for a covering index.  She indicated that she’s even created indexes with gender as the first column in the index.  I’ve got lots to learn still!

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  • KDE Sometimes Glitches On Wakeup

    - by Mew
    Well, a picture is work 1k words: Looks bad, huh? I am using the 331-updates latest 331.67 drivers from NVidia's website on a Dell Latitude e6400. Everything else is up-to-date. This only happens when I resume from sleep, or I switch to a VT and back. It also doesn't ALWAYS happen, which I find odd. Graphics Card: Nvidia Quadro NVS160M UPDATE AFTER TESTING: This problem only exists with KDE (specifically QT). I can go into Unity or Mint or any non QT-based GUI and it works perfectly with no resume errors. UPDATE: This only happens when I use KWin (and KDE). I have upgraded to 14.04 and the problem is not occurring as frequently. Also, sometimes this effect doesn't happen, but instead the top menu bar simply goes out of focus with the rest of the screen goes blank.

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  • Fails to boot after upgrade, stuck on winbind package

    - by Praetorian
    I started the upgrade from 11.04 to 11.10 last night. Once it got the installing packages part I left the computer unattended the rest of the night. When I checked it this morning the screen was blank and I couldn't get it to turn on. So I cycled power, and now I get the "Ubuntu 11.10" screen with the dots underneath, but then it gets to a blank screen and nothing more. I can get to the command line in recovery mode; here's a list of the things I've tried so far sudo apt-get update - the very first repository it checked sat at 0% for a long time (network cable is plugged in), so I cancelled with Ctrl+C Thought it might be a problem with display drivers, so I tried sudo apt-get install nvidia-glx - this gave me an error saying dpkg has been interrupted, manually run sudo dpkg --configure -a sudo dpkg --configure -a this installed / updated a bunch of stuff but got stuck at Starting Winbind daemon winbind Restarted and tried sudo dpkg --configure -a again but it gets stuck at same Windbind step What else can I do to fix this problem?

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  • How to set up a one-man research in the difference between BDD and Waterfall?

    - by Martijn van der Maas
    Earlier, I asked a question about how to measure the quality of a project. The outcome of that question was that the quality of the project can be divided into two parts: Internal quality (code quality, measurable by code quality metrics) External quality (Acceptance test, how well the software meets the requirements) So based on that, I want to set up some research and validate the outcome of the project. The problem is, I will conduct this research on my own, so it's not possible to run the project once in BDD style and the other one in waterfall by myself. It's also not possible to compare BDD and waterfall projects on a larger scale, due to the fact that there are not enough BDD projects that can be measured because of the age of BDD. So, my question is: did anybody face this problem? How could I execute my experiment in such a way that it is of scientific value?

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  • Secret of SQL Trace Duration Column

    - by Dan Guzman
    Why would a trace of long-running queries not show all queries that exceeded the specified duration filter?  We have a server-side SQL Trace that includes RPC:Completed and SQL:BatchCompleted events with a filter on Duration >= 100000.  Nearly all of the queries on this busy OLTP server run in under this 100 millisecond threshold so any that appear in the trace are candidates for root cause analysis and/or performance tuning opportunities. After an application experienced query timeouts, the DBA looked at the trace data to corroborate the problem.  Surprisingly, he found no long-running queries in the trace from the application that experienced the timeouts even though the application’s error log clearly showed detail of the problem (query text, duration, start time, etc.).  The trace did show, however, that there were hundreds of other long-running queries from different applications during the problem timeframe.  We later determined those queries were blocked by a large UPDATE query against a critical table that was inadvertently run during this busy period. So why didn’t the trace include all of the long-running queries?  The reason is because the SQL Trace event duration doesn’t include the time a request was queued while awaiting a worker thread.  Remember that the server was under considerable stress at the time due to the severe blocking episode.  Most of the worker threads were in use by blocked queries and new requests were queued awaiting a worker to free up (a DMV query on the DAC connection will show this queuing: “SELECT scheduler_id, work_queue_count FROM sys.dm_os_schedulers;”).  Technically, those queued requests had not started.  As worker threads became available, queries were dequeued and completed quickly.  These weren’t included in the trace because the duration was under the 100ms duration filter.  The duration reflected the time it took to actually run the query but didn’t include the time queued waiting for a worker thread. The important point here is that duration is not end-to-end response time.  Duration of RPC:Completed and SQL:BatchCompleted events doesn’t include time before a worker thread is assigned nor does it include the time required to return the last result buffer to the client.  In other words, duration only includes time after the worker thread is assigned until the last buffer is filled.  But be aware that duration does include the time need to return intermediate result set buffers back to the client, which is a factor when large query results are returned.  Clients that are slow in consuming results sets can increase the duration value reported by the trace “completed” events.

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