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  • Is it more valuable to double major in Computer Science/Software Engineering or get an undergraduate CS degree with a Masters in SE?

    - by Austin Hyde
    A friend and I (both in college) are currently in a debate over which is better, in terms of employment opportunities, experience, and education: a Bachelors degree in both Computer Science and Software Engineering, or a Bachelors in Computer Science with a Masters in Software Engineering. My point of view is that I would rather go to school for 4-4.5 years to learn both sides of the field, and be out working on real projects gaining real experience, by going the double major route. His point of view is that it would look better to potential employers if he had a Bachelors in CS and Masters in SE. That way, when he's finally done after 4 years of CS and 2-4 of SE (depending on where he goes), he can pretty much have his choosing of what he wants to do. We are both in agreement on the distinction between the two degrees: CS is "traditional" and about the theory of algorithms, data structures, and programming, where SE is the study of the design of software and the implementation of CS theory. So, what's your stance on this debate? Have you gone one route or another? And most importantly, why?

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  • Game Development Blog Aggregators [duplicate]

    - by Eric Richards
    This question already has an answer here: Game development Blogs [closed] 57 answers I'm a big fan of link collection blogs like Alvin Ashcraft's Morning Dew, Jason Haley's Interesting Finds, and Chris Alcock's The Morning Brew for aggregating interesting blogs on .Net related development stuff. I'd like to find something similar for game development blogs. I follow GameDev.net's articles and developer journals, and #AltDevBlogADay, but would love to see some more, if anyone knows of any interesting links.

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  • How common is prototyping as the first stage of development?

    - by EpsilonVector
    I've been taking some software design courses in the past few semesters, and while I see the benefit in a lot of the formalism, I still feel like it doesn't tell me anything about the program itself. You can't tell how the program is going to operate from the Use Case spec, even though it discusses what the program can do, and you can't tell anything about the user experience from the requirements document, even though it can include QA requirements. ...sequence diagrams are as good a description of how the software works as the call stack, in other words- very limited, highly partial view of the overall system, and a class diagram is great for describing how the system is built, but is utterly useless in helping you figure out what the software needs to be. Where in all this formalism is the bottom line- how the program looks, operates, and what experience it gives? Doesn't it make more sense to design off of that? Isn't it better to figure out how the program should work via a prototype and strive to implement it for real? I know that I'm probably suffering from being taught engineering by theoreticians, but I got to ask, do they do this in the industry? How do people figure out what the program actually is, not what it should conform to? Do people prototype a lot? ...or do they mostly use the formal tools like UML and I just didn't get the hang of using them yet?

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  • Which Project Management Software is adequate for Software & Non-Software Projects?

    - by cusack
    PMS = (Project Management Software) I used trac for software development some time ago. Right now I'm searching for a new more powerful (scheduling, gantt charts, ...) free solution (as in free beer ;-) and free to install on my server) for my current software project. Besides the current software project, abstract project management features like issue-tracking & scheduling would be great for coordinating a group of volunteers for real-life projects as well. I would want one solution for both purposes, so that I have the hassle of installation, getting used to the system and administration only once. So I tried redmine but the problem is it seems to be designed for software projects only. I can't suggest such a solution for the volunteer-group if tickets/issues would have to be of type bug, feature, ... I shortlisted the following six PMS from the wikipedia comparison http://en.wikipedia.org/wiki/List_of_project_management_software Project.net Project-Open Redmine Trac Endeavour Software Project Management eGroupWare I guess they are all more or less fine for software development but would you consider any of these to be good for the non-software project as well? Cliff Notes: I would want a start page situation like in trac. The start-page is a wiki presenting the project and not the PMS. But you can log into the PMS from there. Feature-wish list: wiki, Issue tracking, revision control, scheduling & gantt charts, forums (least important) (Btw: I'm very aware that I can't expect everything to be perfect ;-) 1.)Do you know a suitable solution for software and real-life projects or a highly customizable PMS where I can easily remove sth. like "browse source"(trac) and rename things like ticket/issue-types "bug", "feature"? 2.)Any experience good/bad with the above mentioned six PMS? I would personally guess that "Redmine" and "Endeavour Software Project Management" are too focused on software projects.

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  • What's the best project management software for internal dev. 5 man shop

    - by P.Brian.Mackey
    I work for a large corporation, but we do small intranet web application development. Our project management tracking sucks. Its custom software built by a jr. intern. For what its worth, our development style is akin to agile, but there's nothing set in stone...very customer oriented approach. I need project tracking that meets the criteria: Intranet, internal products. Mostly maintenance, some new development. 5 developers 12 products 1 hands-off manager. He really just wants to know estimated man hours, due date for dev, QA and release. Along with a short description of the project. Free or super cheap. Bonus Simple pretty UI. Think pretty charts. Hope I covered everything. Please ask for any clarification. If you read dreaming in code, the company uses some project tracking software that sounds pretty sweet. Note, we do have Team Foundation Server. I already tried pushing its use as PM tracking, but its too complicated. I can't get people to sit and train. So this software has to be easy.

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  • I'm hoping to start an online supermarket and needs advice on open source shopping cart software and applications..

    - by Betterman Simidi
    I have been researching on both open source software and off-the-shelf software for an online supermarket project in Africa. I have now narrowed by search to X-cart and the PHP based PrestaShop shopping carts. My plan is to acquire an open source shopping cart either by purchasing or as a free open source cart and hire a local developer to customize it to our local needs. I have been doing the demo for x-cart for three weeks now and had thought it might work best for us but after going through the 600 page manual and I'm concerned with how far it can be localized. Yesterday i was looking at the possible Prestashop free open source cart and i seem to like the back-end. Didn't like the back-end for Magento much but from reviews conducted by third-parties they seem to recommend it. I'm now wondering whether i should have a developer start the whole project from scratch, or use an open source software such us PrestaShop or get x-cart which can then be customized. Note that my store will have thousands of products and services including groceries and so i want something that can handle upto 500,000 products and over. Kindly advice. 93276

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  • Is it possible to set a VPN through Tor? and have functionality for Software Updates?

    - by moazhmi
    Gday, I have been trying to do a software update on Trusty both on terminal and software update app but that hasnt been successful, apparently my ISP has a broken transparent proxy. moazhmi@moazhmi-K52F:~$ wget -S http://extras.ubuntu.com/ubuntu/dists/trusty/InRelease --2014-06-04 17:34:52-- http://extras.ubuntu.com/ubuntu/dists/trusty/InRelease Resolving extras.ubuntu.com (extras.ubuntu.com)... 91.189.92.152 Connecting to extras.ubuntu.com (extras.ubuntu.com)|91.189.92.152|:80... connected. HTTP request sent, awaiting response... HTTP/1.1 200 OK Content-Type: text/html; charset=UTF-8 Content-Length: 213 Date: Wed, 04 Jun 2014 14:34:52 GMT Server: Apache/2.2.22 (Ubuntu) Connection: Keep-Alive Vary: Accept-Encoding Length: 213 [text/html] Saving to: ‘InRelease’ 100%[======================================>] 213 --.-K/s in 0s 2014-06-04 17:34:52 (22.1 MB/s) - ‘InRelease’ saved [213/213] I was advised to refer back to the ISP with a complaint but that has returned with peanuts. My Question is - Is it possible to set a VPN through TOR , i.e whereas I can run software updates through terminals or the app . the browsing is out of question here as I need to update which I am not able to do / only on 12.04.

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  • Does 3d modeling software *choice used during asset creation affect performance at runtime

    - by user134143
    Does software used to create 3d assets (for game development specifically) have an impact on the efficiency of the program? In other words, is it possible to reduce the operating footprint of an application merely by utilizing alternative development software during production of 3d assets? If you use two different applications to create a 3 dimensional image of a box, can one of them result in better performance if aspects of the image are identical? I am attempting to get the information I need without causing unnecessary debate over specific software choice.

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  • Will people respect a Masters of Science in IT w/software engineering concentration from RPI?

    - by twneale
    Here's my thing: I got my undergraduate degree in political science, then a law degree. Then I figured out that I love programming and I'm pretty good at it too. It's fun and rewarding enough for me that I'd prefer to do it for a living over almost any form of pure law practice. So I'm looking at getting a masters degree to put some weight behind a possible career switch. If I actually want to develop software (web, in particular), would people in programming circles respect a master's of science in IT? Specifically, consider as an example the MS in IT from Rensselaer Polytechnic Institute (with a concentration in software engineering). Here's the home page: http://www.rpi.edu/IT/graduate/masters_program.html In particular, I mean to draw a contrast between IT as specifically contemplated by the RPI masters program (an interdisciplinary tech/business program) and other MS degrees in computer science or software engineering that focus more on the science and technical aspects. I guess I want to make sure that other programmers would respect my credentials and not consider me as different or underqualified based on the connotations of the phrase "IT". I believe RPI has an unimpeachable reputation for hard science, and the program seems excellent, but it still matters to me how people in industry would perceive it.

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  • How to justify rewriting/revamping legacy software in a business case?

    - by sxthomson
    I work for a great little software company which makes good revenue from our main software package. The problem for me is that it's almost unmaintainable. It's written in Delphi 7 (has upgraded versions over time) and has been worked on by a lot of developers over the past 20 or so years. The software lacks any meaningful architecture - there's no object orientation whatsoever, horrible amounts of cyclical dependencies and an over-reliance on global variables to name just a few things. Another huge thing for me is Delphi 7 does NOT support 64-bit. The problem here for me is that my management team don't care about technical things, they want to know why they should care. Obviously that's expected, so what I'm asking here is for some guidance, or tales, or pitfalls about this kind of thing. There's a few things I would love to include, namely for me, the length of time taken to debug/write a feature in "legacy" code, versus coherent, well structured OO code. Does anyone know of any blog posts or the like where this is talked about? For us in the company this is a huge reason. Despite being decent developers we feel like writing a new feature is just piling more rubbish on top. On top of that, even for me who has a decent level of understanding of the code, changing things is infuriating - a small change can have a ridiculous domino effect. Anyone have any experiences they'd like to share?

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  • In which fields does quality of the software product matter as much as the completion time?

    - by Nav
    Someone told me that if the software product meets clients expectations, it is good quality. But I've worked with Interaction Designers (the same kind of people who made Gmail's interface and usability so cool!), and I've loved working with them because even though they came up with hundreds of changes in requirements, and emphasised on many many subtle details, when the software was complete, I could look at the product and say WOW! The current place I work, the only thing that matters is completing the project on time. As long as it works and as long as the client says it's ok, nobody bothers to improve it. I'm not talking about gold-plating, but I believe that for a programmer to enjoy his (well, maybe her too ;) ) job, they should be able to proudly say that "Hey, I made that software" and that comes only when the product is of good quality. Apart from your opinions on this, I'd also like to know which fields (Eg. Aerospace, Finance etc.) could I find companies (or you could mention the company name) where the quality of a product is as important as completing the project on time?

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  • How do you work on Strategic Development initiatives when Tactical work takes priority?

    - by Shaun F
    My day-to-day job consists of maintaining large volume websites and this has given me exposure to developing better methods to develop and maintain the code. This has also given me a large body of knowledge in the code base in terms of troubleshooting that is beneficial to the company. I'm also the maintainer of an IDE plug in I created to help navigate and generate code that is used. Operationally though, my job is to handle any client requests that come in of that are emergencies and make any enhancements and additions to the code base required. This work, along with the daily managing and feeding of the the project managers will take up my entire day. How does one manage the time between the tactical day job and the strategic initiatives? How does one get and ask for recognition for taking strategic initiatives? Is the 8-9 hour day just not going to cut it? Is there even a job out there for programmers to develop strategic initiatives and solutions for a company? I want to also point out that this isn't a problem with the company at all. I think this is more of a personal-improvement decision. Nobody will say no to the improvements at all. I believe in making the things happen but I don't think I'm going to get time from the company to do it...

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  • What would be a good starting point for development of a 3D application for representation of struct

    - by Lela Dax
    I was thinking QT on OpenGL. Multiplatform ability and being able to be closed (at no cost) at a later point would be important points. But I'm very interested in finding a way that is not only viable but also has the least amount of reinvention of the wheel. e.g. "Why not Ogre? A ready powerful 3D engine without reinventing that part". But I'm very uncertain in what is the optimal collection of tools for that job.

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  • Which metric/list should be used to evaluate whole software development team?

    - by adt
    Title might be seem vague, so let me tell you a little bit history what i am trying to clarify question. I have been hired as a consultant for a corporate's small developement divison ( The company also owns a couple of software dev. companies) My ex manager runs a BI team, with reportes, analyts and developers. He asked me to evaluate overall design, software developement process and code quality . Here what i found, Lots of copy/paste code everywhere ( no reuse ) Even though they have everything TFS, VS Ultimate etc, No Build process , No Cruise Control.net / team city... No unit tests Web Pages with 3700 lines of code, Lots of huge functions ( which can be divided into smaller one's ) No naming convention both db and c# code No 3r party or open source project No IoC No Seperation Of Concerns No Code Quality Check ( NDepend or FxCope or nothing ) No Code Review No Communication within the team They claim they wrote an application framework ( 6 months 3 persons), but I would hardly call a framework ( of course no unit test, there are some but all commented out). Framework contains 14 projects but there are some projects with 1 file 20 lines of code . Honestly, what people are doing fixing bug all thr day( which will provide more bugs eventually), they are kind of isolated from community, some team members even dont know github or stackoverflow they probably went there with google but they dont know about it. So here is question, Is This list ok ? Or am i being picky? Since I dont have any grudge against them, I just want to be fair, honest and I would like to hear you suggestions, before I would submit this list. And since this list also will be review by software division's manager, I dont want any heart break or something like this. http://www.hanselman.com/altnetgeekcode/ For example I would love to such lists, i cant make references. Thanks in advance.

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  • Screen Flickering: Hardware or Software?

    - by Wesley
    I have a Samsung N120 netbook (upgraded to 2GB DDR2 RAM) and there has been a screen flickering issue for some time now. However, I have not been able to accurately determine whether it is a software or hardware issue. Here are some of the symptoms: The flicker is white-colored and shows up as vertical lines. Flickering or not, there may be occasionally some random blue patterns (no image distortion) The screen tends to flicker more when the screen is not tilted back all the way. When tilting the screen back and forth, the screen will usually flicker. Some images on the screen may randomly distort without full-on flickering. The screen will flicker only on certain websites, but not on others. A certain part of a webpage may constantly be distorted randomly, even when scrolling. While flickering, the mouse will not move though I'm moving my finger along the touchpad. A connected external monitor does not have any problems. The flickering is completely random and does not seem to follow any CPU/GPU usage trends. Flickering usually gets worse when the screen brightness is turned higher. There will be flickering on battery and while plugged in. Search up "Samsung N120 - Screen Flickering" on YouTube for an idea of what the flickering looks like. However, there is no visible distortions and the flickering seems to stop when the screen has dimmed. Since the problems started, I tried formatting and using Windows 7, then formatted again and went back to Windows XP. The screen was also replaced sometime during this past summer. The uninstallation of the Samsung Battery Manager (on the original install of XP) seemed to reduce the flicker partially, but eventually got worse. So, what could possibly be the problem?

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  • Windows Firewall Software to Filter Transit Traffic

    - by soonts
    I need to test my networking code for Nintendo Wii under the conditions when some specific Internet server is not available. Wii is connected to my PC with crossover ethernet cable. PC has 2 NICs. PC is connected to hardware router with ethernet cable. The hardware router serves as NAT and has an internet connected to its uplink. I set the Wii to be in the same lan as PC by using Windows XP Network bridge. I can observe the WII network traffic using e.g. Wireshark sniffer. Is there a software firewall that can selectively filter out transit traffic? (e.g. block outgoing TCP connections to 123.45.67.89 to port 443) I tried Outpost Pro 2009 and Comodo. Outpost firewall blocks all transit traffic with it's implicit "block transit packet" rule. If the transit traffic is explicitly allowed by creating the system-wide low level rule, then it's allowed completely and no other filter can selectively block it. Comodo firewall only process rules when the packet has localhost's IP as either source or destination, allowing the rest of the traffic. Any ideas? Thanks in advance! P.S. Platform is Windows XP 32 bit, no other OSes is allowed, Windows ICS (Internet Connection Sharing) doesnt work since the Wii is unable to connect, becides I don't like the idea of adding one more level of NAT.

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  • How to create a software raid5 array without a spare

    - by Yannick M.
    I am trying to create a software raid5 array using mdadm: $ linux # mdadm --create --verbose /dev/md0 --level=5 --raid-devices=4 --spare-devices=0 /dev/sda1 /dev/sdb1 /dev/sdc1 /dev/sdd1 mdadm: layout defaults to left-symmetric mdadm: chunk size defaults to 64K mdadm: array /dev/md0 started. However when inspecting /proc/mdstat Personalities : [raid6] [raid5] [raid4] md0 : active raid5 sdd1[4] sdc1[2] sdb1[1] sda1[0] 2930279808 blocks level 5, 64k chunk, algorithm 2 [4/3] [UUU_] [>....................] recovery = 0.3% (2970496/976759936) finish=186.1min speed=87172K/sec unused devices: <none> It seems one drive isn't active, so I check the details of the array: /dev/md0: Version : 00.90.03 Creation Time : Tue Jul 21 16:29:53 2009 Raid Level : raid5 Array Size : 2930279808 (2794.53 GiB 3000.61 GB) Used Dev Size : 976759936 (931.51 GiB 1000.20 GB) Raid Devices : 4 Total Devices : 4 Preferred Minor : 0 Persistence : Superblock is persistent Update Time : Tue Jul 21 16:29:53 2009 State : clean, degraded, recovering Active Devices : 3 Working Devices : 4 Failed Devices : 0 Spare Devices : 1 Layout : left-symmetric Chunk Size : 64K Rebuild Status : 0% complete UUID : ce8b2f40:821d003c:0027688e:a70977ec Events : 0.1 Number Major Minor RaidDevice State 0 8 1 0 active sync /dev/sda1 1 8 17 1 active sync /dev/sdb1 2 8 33 2 active sync /dev/sdc1 4 8 49 3 spare rebuilding /dev/sdd1 And it seems there are only 3 active devices, with one spare. Is it just me, or something wrong here?

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  • Converting software RAID1 to RAID10 for /boot

    - by luckytaxi
    Array info: /dev/md0 - /dev/sda1 and /dev/sdb1 /dev/md2 - /dev/sda2 and /dev/sdb2 Partition info: /boot - /dev/md0 / - /dev/md1 I have two drives that are setup as RAID1 using software RAID on Redhat. I added two additional drives (same size) and I would like to conver the RAID1 to a RAID10. The problem I'm having is adding the last drive to the array. I've gotten as far as creating a RAID10 with two missing devices but as soon as I add the last drive, all hell breaks loose. It seems /dev/sda1 is the culprit. What I'm not too sure about is how to create the RAID10. I've tried the following mdadm --create /dev/md2 --level=raid10 --raid-device=4 /dev/sdc1 missing /dev/sdd1 missing I then proceeded to fail /dev/sdb1 from /dev/md0 and added that partition to /dev/md2. I proceeded to install the MBR on EACH partition since boot resides on /dev/sdx1 on each drive. As a test, all is well, I'm able to boot back into the system once I do a quick reboot. Now, when I go add the last drive /dev/sda1, it breaks. I attempted to install grub on /dev/sda1 and I get the following ... grub> root (hd0,0) /dev/sda root (hd0,0) /dev/sda Filesystem type is ext2fs, partition type 0xfd grub> setup (hd0) setup (hd0) Checking if "/boot/grub/stage1" exists... no Checking if "/grub/stage1" exists... no Error 2: Bad file or directory type At this point, the array is hosed I believe. I rebooted the server and it refuses to boot.

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  • mkfs Operation Takes Very Long on Linux Software Raid 5

    - by Elmar Weber
    I've set-up a Linux software raid level 5 consisting of 4 * 2 TB disks. The disk array was created with a 64k stripe size and no other configuration parameters. After the initial rebuild I tried to create a filesystem and this step takes very long (about half an hour or more). I tried to create an xfs and ext3 filesystem, both took a long time, with mkfs.ext3 I observed the following behaviour, which might be helpful: writing inode tables runs fast until it reaches 1053 (~ 1 second), then it writes about 50, waits for two seconds, then the next 50 are written (according to the console display) when I try to cancel the operation with Control+C it hangs for half a minute before it is really canceled The performance of the disks individually is very good, I've run bonnie++ on each one separately with write / read values of around 95 / 110MB/s. Even when I run bonnie++ on every drive in parallel the values are only reduced by about 10 MB. So I'm excluding hardware / I/O scheduling in general as a problem source. I tried different configuration parameters for stripe_cache_size and readahead size without success, but I don't think they are that relevant for the file system creation operation. The server details: Linux server 2.6.35-27-generic #48-Ubuntu SMP x86_64 GNU/Linux mdadm - v2.6.7.1 Does anyone has a suggestion on how to further debug this?

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  • How to interrupt software raid resync?

    - by Adam5
    I want to interrupt a running resync operation on a debian squeeze software raid. (This is the regular scheduled compare resync. The raid array is still clean in such a case. Do not confuse this with a rebuild after a disk failed and was replaced.) How to stop this scheduled resync operation while it is running? Another raid array is "resync pending", because they all get checked on the same day (sunday night) one after another. I want a complete stop of this sunday night resyncing. [Edit: sudo kill -9 1010 doesn't stop it, 1010 is the PID of the md2_resync process] I would also like to know how I can control the intervals between resyncs and the remainig time till the next one. [Edit2: What I did now was to make the resync go very slow, so it does not disturb anymore: sudo sysctl -w dev.raid.speed_limit_max=1000 taken from http://www.cyberciti.biz/tips/linux-raid-increase-resync-rebuild-speed.html During the night I will set it back to a high value, so the resync can terminate. This workaround is fine for most situations, nonetheless it would be interesting to know if what I asked is possible. For example it does not seem to be possible to grow an array, while it is resyncing or resyncing "pending"]

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  • mkfs Operation Takes Very Long on Linux Software Raid 5

    - by Elmar Weber
    I've set-up a Linux software raid level 5 consisting of 4 * 2 TB disks. The disk array was created with a 64k stripe size and no other configuration parameters. After the initial rebuild I tried to create a filesystem and this step takes very long (about half an hour or more). I tried to create an xfs and ext3 filesystem, both took a long time, with mkfs.ext3 I observed the following behaviour, which might be helpful: writing inode tables runs fast until it reaches 1053 (~ 1 second), then it writes about 50, waits for two seconds, then the next 50 are written (according to the console display) when I try to cancel the operation with Control+C it hangs for half a minute before it is really canceled The performance of the disks individually is very good, I've run bonnie++ on each one separately with write / read values of around 95 / 110MB/s. Even when I run bonnie++ on every drive in parallel the values are only reduced by about 10 MB. So I'm excluding hardware / I/O scheduling in general as a problem source. I tried different configuration parameters for stripe_cache_size and readahead size without success, but I don't think they are that relevant for the file system creation operation. The server details: Linux server 2.6.35-27-generic #48-Ubuntu SMP x86_64 GNU/Linux mdadm - v2.6.7.1 Does anyone has a suggestion on how to further debug this?

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  • Growing a Linux software RAID5 array

    - by chrismetcalf
    On my home file server, I've got a 1.5TB software RAID5 array, built from four 500gb Western Digital drives. I've got a fifth drive that I usually run as a hot spare (but have out of the array at the moment), but if I can I'd like to add that to the array and grow it to 2TB since I'm running out of space. I Googled for guidance, but there seem to be a lot of differing opinions out there (many of them probably now out-of-date) as to whether or not that is possible and/or smart. What's the right way to go about this, or should I start looking into building a new array with more space? Version details: %> cat /etc/issue Debian GNU/Linux 5.0 \n \l %> uname -a Linux magrathea 2.6.26-1-686-bigmem #1 SMP Sat Jan 10 19:13:22 UTC 2009 i686 GNU/Linux %> /sbin/mdadm --version mdadm - v2.6.7.2 - 14th November 2008 %> cat /proc/mdstat Personalities : [raid1] [raid6] [raid5] [raid4] md1 : active raid1 hdc1[0] hdd1[1] 293033536 blocks [2/2] [UU] md0 : active raid5 sde1[3] sda1[0] sdc1[2] sdb1[1] 1465151808 blocks level 5, 64k chunk, algorithm 2 [4/4] [UUUU]

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  • Bad performance with Linux software RAID5 and LUKS encryption

    - by Philipp Wendler
    I have set up a Linux software RAID5 on three hard drives and want to encrypt it with cryptsetup/LUKS. My tests showed that the encryption leads to a massive performance decrease that I cannot explain. The RAID5 is able to write 187 MB/s [1] without encryption. With encryption on top of it, write speed is down to about 40 MB/s. The RAID has a chunk size of 512K and a write intent bitmap. I used -c aes-xts-plain -s 512 --align-payload=2048 as the parameters for cryptsetup luksFormat, so the payload should be aligned to 2048 blocks of 512 bytes (i.e., 1MB). cryptsetup luksDump shows a payload offset of 4096. So I think the alignment is correct and fits to the RAID chunk size. The CPU is not the bottleneck, as it has hardware support for AES (aesni_intel). If I write on another drive (an SSD with LVM) that is also encrypted, I do have a write speed of 150 MB/s. top shows that the CPU usage is indeed very low, only the RAID5 xor takes 14%. I also tried putting a filesystem (ext4) directly on the unencrypted RAID so see if the layering is problem. The filesystem decreases the performance a little bit as expected, but by far not that much (write speed varying, but 100 MB/s). Summary: Disks + RAID5: good Disks + RAID5 + ext4: good Disks + RAID5 + encryption: bad SSD + encryption + LVM + ext4: good The read performance is not affected by the encryption, it is 207 MB/s without and 205 MB/s with encryption (also showing that CPU power is not the problem). What can I do to improve the write performance of the encrypted RAID? [1] All speed measurements were done with several runs of dd if=/dev/zero of=DEV bs=100M count=100 (i.e., writing 10G in blocks of 100M). Edit: If this helps: I'm using Ubuntu 11.04 64bit with Linux 2.6.38. Edit2: The performance stays approximately the same if I pass a block size of 4KB, 1MB or 10MB to dd.

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  • Desktop Provisioning for a Small Linux Software Development Team

    - by deakblue
    Goal: Get a small team using a standard development image rather than 4 software devs setting up their own environments. Why: it takes a day or days to install a distro, build-specific libraries, tools like editors and IDEs, mysql, couchdb, java, maven, python, android-sdk, etc. It's a giant PITA that when repeated 4 times by 4 developers (not sys admins) wastes time and generates annoying divergences that crop up later (it-builds-on-my-box syndrome). There's no sharing of productivity, settings, tricks, scripts, set-ups. Some of this is helped by segregating the build systems into headless virtualbox images. This doesn't really address tooling though or the GUI-desktop dev that needs doing. So I see three basic strategies, ghosting, virtualization, and finally creating a kind of in-house linux distro (I guess Google does something like this). The target dev environment is based on Debian OpenBox and must allow a mix of 3rd gen Core i7 notebooks 8GB-minimum to work both single and multihead. Important, the lappies are not the same, but a mix of 2012 macbooks and PCs. So: virtualization: is doing all of your work within a VM, like VirtualBox, practical on this hardware or annoying. ghosting: will laptops from different manufacturers make this impractical. DIY distro: short of scripting a bunch of package installs, I don't know if there's any "distro-maker" that could keep this from being an epic project of scripting package installs. So any advice?

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