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• Cluster Nodes as RAID Drives

  - by BuckWoody

  I'm unable to sleep tonight so I thought I would push this post out VERY early. When you don't sleep your mind takes interesting turns, which can be a good thing. I was watching a briefing today by a couple of friends as they were talking about various ways to arrange a Windows Server Cluster for SQL Server. I often see an "active" node of a cluster with a "passive" node backing it up. That means one node is working and accepting transactions, and the other is not doing any work but simply "standing by" waiting for the first to fail over. The configuration in the demonstration I saw was a bit different. In this example, there were three nodes that were actively working, and a fourth standing by for all three. I've put configurations like this one into place before, but as I was looking at their architecture diagram, it looked familar - it looked like a RAID drive setup! And that's not a bad way to think about your cluster arrangements. The same concerns you might think about for a particular RAID configuration provides a good way to think about protecting your systems in general. So even if you're not staying awake all night thinking about SQL Server clusters, take this post as an opportunity for "lateral thinking" - a way of combining in your mind the concepts from one piece of knowledge to another. You might find a new way of making your technical environment a little better. Share this post: email it! | bookmark it! | digg it! | reddit! | kick it! | live it!

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• Gateway ZA8 Netbook graphics Issue

  - by Hansel

  The graphics keep tearing and are barely usable anytime I try to use my Netbook. And I did a full install with Ubuntu so I'm pretty much stuck. These are the specs of the Netbook: Processor AMD Athlon™ 64 L110 Single-Core Processor (1.2GHz, 800MHz FSB, 512KB L2 Cache)6 Operating System Genuine Windows Vista® Home Basic (32-bit) with SP1 Display 11.6" HD WXGA Ultrabright™ LED-backlit Display (1366 x 768 resolution, 16:9 aspect ratio)7 Memory 2048MB DDR2 533MHz SDRAM Single Channel Memory8 Hard Drive 250GB SATA hard drive2 Color Classic and Elegant Design with Cherry Red finish Wireless Network 802.11b/g Wi-Fi CERTIFIED®3 Adapter AC Adapter Application Software Microsoft® Works, Microsoft® Money Essentials, Microsoft® Office Home and Student 2007 (60-day complimentary trial period)1 Battery 6-Cell Lithium Ion (5200mAh) Chassis Chassis with ATI Radeon® X1270 Graphics and AMD RS690E Chipset8 Dimensions (Box) 3.1" (H) x 14.8" (W) x 10.1" (D) or 80mm (H) x 376mm (W) x 256mm (D) Dimensions (System) 1.03" (H) x 11.26" (W) x 7.99" (D) or 26.4mm (H) x 286mm (W) x 203mm (D) External Ports (3) USB 2.0, VGA Connector Keyboard and Mouse Keyboard with Multi-Gesture Touchpad Media Card Reader Multi-in-1 Digital Media Card Reader (Memory Stick®, Memory Stick Pro™, MultiMediaCard, Secure Digital™, xD-Picture Card™) Network 10/100 Ethernet LAN (RJ-45 port) What can I do?

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• Can I send some text to the STDIN of an active process running in a screen session?

  - by Richard Gaywood

  I have a long-running server process inside a screen session on my Linux server. It's a bit unstable (and sadly not my software so I can't fix that!), so I want to script a nightly restart of the process to help stability. The only way to make it do a graceful shutdown is to go to the screen process, switch to the window it's running in, and enter the string "stop" on its control console. Are there any smart redirection contortions I can do to make a cronjob send that stop command at a fixed time every day?

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• Huge procedurally generated 'wilderness' worlds

  - by The Communist Duck

  Hi. I'm sure you all know of games like Dwarf Fortress - massive, procedural generated wilderness and land. Something like this, taken from this very useful article. However, I was wondering how I could apply this to a much larger scale; the scale of Minecraft comes to mind (isn't that something like 8x the size of the Earth's surface?). Pseudo-infinite, I think the best term would be. The article talks about fractal perlin noise. I am no way an expert on it, but I get the general idea (it's some kind of randomly generated noise which is semi-coherent, so not just random pixel values). I could just define regions X by X in size, add some region loading type stuff, and have one bit of noise generating a region. But this would result in just huge amounts of islands. On the other extreme, I don't think I can really generate a supermassive sheet of perlin noise. And it would just be one big island, I think. I am pretty sure Perlin noise, or some noise, would be the answer in some way. I mean, the map is really nice looking. And you could replace the ascii with tiles, and get something very nice looking. Anyone have any ideas? Thanks. :D -TheCommieDuck

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• fail2ban with Cloudflare

  - by tatersalad58

  I'm using fail2ban to block web vulnerability scanners. It is working correctly when visiting the site if CloudFlare is bypassed, but a user can still access it if going through it. I have mod_cloudflare installed. Is it possible to block users with IPtables when using Cloudflare? Ubuntu Server 12.04 32-bit Access.log: 112.64.89.231 - - [29/Aug/2012:19:16:01 -0500] "GET /muieblackcat HTTP/1.1" 404 469 "-" "-" Jail.conf [apache-probe] enabled = true port = http,https filter = apache-probe logpath = /var/log/apache2/access.log action = iptables-multiport[name=apache-probe, port="http,https", protocol=tcp] maxretry = 1 bantime = 30 # Test Apache-probe.conf [Definition] failregex = ^<HOST>.*"GET \/muieblackcat HTTP\/1\.1".* ignoreregex =

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• Problems in Linux Mint 13 MATE with NTFS partitions

  - by usr

  I'm using Linux Mint 13 MATE (32 bit). With Caja file manager (based on Nautilus 2.x) I can create, modify and remove folders and files on NTFS partitions whitout problems. But, for example, when I have a compressed file (.zip, .7z, ...) in a NTFS partition I can't extract it (with File-Roller, Peazip, ...). But I can extract the same file in a ext4 partition perfectly. What might the problem be? Are there (maybe) file permissions for each application?

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• Windows 7 - cancel mirror synchronisation

  - by Chris W

  I've got basic disk OS managed disk mirroring setup in Windows 7 for a couple of volumes. After a power failure the mirrors are currently resynching. These are only small volumes of data but the sync has not completed after more than 24 hours. Is there any way to stop this as it's driving me nuts? I need to get the machine back to a usable state to get some work done but it's a bit of a dog whilst this synch is going on. I've tried removing the mirrors but it won't let me do that whilst the re-sync is in progress.

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• Windows 7 - cancel mirror synchronisation

  - by Chris W

  I've got basic disk OS managed disk mirroring setup in Windows 7 for a couple of volumes. After a power failure the mirrors are currently resynching. These are only small volumes of data but the sync has not completed after more than 24 hours. Is there any way to stop this as it's driving me nuts? I need to get the machine back to a usable state to get some work done but it's a bit of a dog whilst this synch is going on. I've tried removing the mirrors but it won't let me do that whilst the re-sync is in progress.

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• Approaches to timed puzzle elements

  - by ndg

  I'm working on a side scrolling game that has a number of timed puzzle elements. As a simple example: I have a number of moving platforms that have been setup to transition in a pattern. Ideally I'd like to ensure that as the player first approaches them, they are in an ideal state -- whereby the player can witness the full transition and more experienced players (i.e: speedrunners) can complete the puzzle immediately without having to wait for the current transition to complete. The issue here, in a nutshell, is that because these platforms begin transitioning at the start of the level, it's impossible to correctly calculate when the player is likely to stumble upon them. I've done a fair bit of Googling but haven't managed to turn up any decent resources with regards to solving a problem like this. The obvious solution is to only begin updating the objects when the player (or more likely: the camera) first encounters them. But this becomes difficult when you consider more complicated situations. It seems like potentially the easiest way of handling this is to have an invisible trigger volume that will tell any puzzle elements located inside of it that the player has 'arrived' upon first colliding with the player. But this would mean I'd have to logically group puzzle elements, which could become fairly messy in a hurry. Take, for instance, a puzzle that appears to the right of the screen. It may take the player a number of seconds to reach it. It would look strange if the elements involved were to remain stationary. But by the time the player arrives, it's likely things will be 'out of sync'. I wanted to post here in the hopes that others know of, or have implemented, a decent solution to this problem?

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• Why does my Mac always crash when I enable `ask for password after screensaver ended`?

  - by Koning Baard XIV

  I have enabled these two things: Placing the mouse-pointer in the bottom-left corner of any display makes the screensaver appear After the screensaver or stand-by has ended, ask for password However, this combination always leads to this (Black Screen of Death) after entering the screensaver with the bottom-left corner: Here are my system specs: Hardware Overview: Model Name: iMac Model Identifier: iMac9,1 Processor Name: Intel Core 2 Duo Processor Speed: 2,66 GHz Number Of Processors: 1 Total Number Of Cores: 2 L2 Cache: 6 MB Memory: 2 GB Bus Speed: 1,07 GHz Boot ROM Version: IM91.008D.B08 SMC Version (system): 1.44f0 Serial Number (system): W89171JF0TF Hardware UUID: 323A90F0-8A2F-5057-B501-2087489E0DFF System Software Overview: System Version: Mac OS X 10.6.3 (10D573) Kernel Version: Darwin 10.3.0 Boot Volume: Macintosh HD Boot Mode: Normal Computer Name: YOU SHOULD NOT KNOW THIS User Name: YOU SHOULD NOT KNOW THIS Secure Virtual Memory: Not Enabled 64-bit Kernel and Extensions: No Time since boot: 11:46 Can anyone help me? Thanks

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• Facebook and flash - why doesn't facebook recognise that I have flash installed?

  - by jaminday

  For some reason when I try to upload photos to facebook from the website, it tells me I need to upgrade my flash player: I definitely have flash installed, as can be seen in the picture, and working fine in youtube etc. My question is two-fold: 1) Does anyone know if this a problem with the version of flash I'm running, Ubuntu, or facebook itself? I get the same problem in Chrome and Firefox, so I know it's not the browser. 2) Is there a workaround or fix for this? As far as I can tell I'm running the very latest flash (on 64-bit Ubuntu 10.10) - but maybe that's the problem? Note: Before everyone starts jumping up and down about using Shotwell or Digikam or some such to upload photos to facebook, I know about these (and do use Shotwell at times). Unfortunately Shotwell only lets you upload to a Profile, but doesn't (as far as I can tell) let you upload to a facebook Page of which I am an administrator, so I am forced do it through the website. Using the simple uploader as seen in the first picture is horribly slow and tedious, and often times out while uploading. Of course if anyone knows of any alternate ways to upload to facebook pages I'd love to hear 'em!

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• tweak windows 7 virtual memory and cache / caching settings

  - by bortao

  im on windows 7 64 bit, with 4gb of memory whenever i copy or deal with a big ammount of data, windows swaps out everything from memory to the virtual memory swapfile, to make room to data cache. the problem is: i dont really need caching of this data im copying, its being copied only once, cacheing this data won't help me. on the other hand, swapping out the programs will give me a big lag time whenever i want to use those open programs again. what i want: restrict data cache to a certain ammount, lets say 1gb, or reserve a certain ammount of memory, lets say 2gb, exclusively for running programs memory. my swap file is on a separate partition, but i still have problems with swapping time.

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• tweak windows 7 virtual memory and cache / caching settings

  - by bortao

  im on windows 7 64 bit, with 4gb of memory whenever i copy or deal with a big ammount of data, windows swaps out everything from memory to the virtual memory swapfile, to make room to data cache. the problem is: i dont really need caching of this data im copying, its being copied only once, cacheing this data won't help me. on the other hand, swapping out the programs will give me a big lag time whenever i want to use those open programs again. what i want: restrict data cache to a certain ammount, lets say 1gb, or reserve a certain ammount of memory, lets say 2gb, exclusively for running programs memory. my swap file is on a separate partition, but i still have problems with swapping time.

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• Windows 2008 R2 server cannot access shares on other servers

  - by Rob

  I have a problem on my new 2008 R2 64-bit server. Essentially the server sometimes refuses to access shares on other server. in the format \\servernam\sharename sometime it works and then for a few hours it doesn't and then at randon it comes back online. This is a local AD network and have even put in a new gigabit switch between all server. All the old 2003 servers work fine so I know DNS and WINS is all ok. I get error 1006 in eventlog saying that my R2 server can't contact the domain controller when it clearly can. Just to add to the config, it is running on a Dell PowerEdge R410, Vmware Esxi 4.0 and R2 is configured as a terminal server. I can always view shares with FQDN This morning net view \\ did not work but net view \\ did. Very random and very frustrating. any ideas? thanks

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• BI Applications 7.9.6.3 and EBS 12.1.3 Vision: Integrated Demo Environments

  - by Mike.Hallett(at)Oracle-BI&EPM

  If you need a combined BI-Applications + eBusiness Suite Applications demonstration environment, or for proof of concept work for your customers, then these versions of images on Oracle Virtual Box are now available for partners to download and use.  To get access to these images, Partners must be OPN members, specialised in OBI or BI-Apps.   This is an integrated Demo/Test Drive/POC/Self Enablement environment including two separate images (in English) representing the entire Oracle Stack – Applications, Middleware, Database, Operating System and Virtual Machine. Minimum Hardware requirements for each image to run separately 4GB RAM Minimum Hardware requirements for both images to run concurrently 8GB RAM Dual CPU 64 bit OS   BI Applications 7.9.6.3 Linux based and running on Oracle Virtual Box and compatible with OVM Image Content: BI Application Analytics demo data extracted from EBS 12.1.3 Vision for Financials and HR using EBS 12.1.3 Vision (image supplied) Built Integration to EBS 12.1.3 Vision image (provided). Fully functional BI Applications 7.9.6.3 software install and configuration Image can be connected to load any data from any other compatible source system. BI Apps Demo data is based on OOTB EBS Vision 12.1.3 Configured to run BI Apps data load for all other modules of EBS 12.1.3 Vision. Includes OBIEE Sample demonstration content Documented scripts for running presentations, demonstrations and Test Drives Image Size: 34GB zip, 84GB unzip.  Min Hardware 4GB RAM         EBS Vision 12.1.3 Linux based and running on Oracle Virtual Box and compatible with OVM Image Content: eBusiness Suite (EBS) Applications Vision 12.1.3 Standard Vision instance with all given setups, configurations and data Source system for BI Apps 7.9.6.3 Image Size: 76GB zip, 300GB unzip.  Min Hardware 4GB RAM Distribution: The Virtual Box images are posted on an external FTP server @ BI Applications 7.9.6.3 EBS12.1.3   To download, Partners need to request the current password to access the images.  To request the current ftp.oracle.com password and the password required to unzip the images, please email Marek Winiarski   Support Contact =  Marek Winiarski: Oracle Partner Solution Consultant

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• Optimizing lifestyle and training

  - by Gabe

  I am a college freshman who has recently discovered a passion for computer science. Having had my first lick of formal python training last semester, I have cast aside my previously hedonist way of life and tunneled my sights on becoming the most rounded and proficient programmer I can be. I know that I'm taking strides in the right direction (I've stopped smoking, I've been exercising every day, I've taught myself C++ and OpenGL, and I've begun training in kung-fu and meditation), yet I am still finding myself struggling to achieve satisfactory results. I would like to be able to spend a good 3-4 hours every day burning through textbooks. I have the time cleared and the resources allocated. The problem lies in the logistics-- I have never taken anything seriously before. Recently I've realized that I am clueless when it comes to taking care of myself and gaining control of my mind, and it drastically hinders my productivity. My question is this: How can I learn to manage my time and take care of myself such that I can spend the maximum amount of time every day studying with steady concentration? Personal tricks would be key here: techniques you use to get yourself to sleep, a diet that yields focus, even computer break stretching routines or active reading techniques. Anything you could think of here would be great. I was a low-life in high school and I have the drive to turn my life around, I'm just quite a bit behind in the way of good habits :)

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• Reliable alert dialogs from the shell

  - by intuited

  I'd like to have a message pop up in response to various system events, mostly in order to be able to set reminders for myself from a shell session. There are a few ways to do this; zenity seems to be the most polished. However, I've found at least two problems with zenity: Messages do not appear on all workspaces. I tried using the gtk option --screen to control this, but they just appear on the current workspace regardless. So if I am switching workspaces as the message comes up, I will not see it. Messages do not appear above all other windows. Specifically, if I am using guake, a new zenity message will appear below the guake window and I won't be able to see it. I tried a few other apps a while back. Both gmessage and xmessage exhibited problem 1; gmessage also exhibited problem 2. I did find that kalarm, which can be scripted from the command line, worked acceptably, but I'm trying to avoid running the KDE stack if possible, and would prefer something lightweight with zenity's versatility. It seems that it might be possible to arrange for these problems to be resolved by setting the WM_CLASS, but I'm in a bit over my head there. It might also be possible to make modifications to the window after it launches with a script, but again I'm not sure where to look for resources on that.

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• Policy Routing with Openvpn?

  - by sadawd

  Dear Everyone I am currently using openvpn for normal browsing. However, I have the following services running: a bit torrent client, a web server, IRC and a git server which I would really want it to not be using my vpn connection (and use my original connection instead). Is there a way to do this? I looked up policy routing and I can't really find any tutorial on how to do this on linux (I am on ubuntu). I don't want the solution to be incredibly complicated - I am pretty new to networking in ubuntu and I only want a very simple solution to this problem. Can someone help me out?

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• Is it me or is developing web based data entry GUIs a big pain?

  - by GregH

  Maybe it's me or maybe it isn't. I don't have a huge amount of experience of developing web based data entry software but do have some. I used to do it quite a bit years ago. Used to use Oracle Forms, Visual Studio, various 4th generation languages, and performing the user interface layout used to be a snap. Now doing the user interface for developing web applications seems to be a huge pain in the rear. Just trying to get text entry fields and widgets to go where they are supposed to go on the screen is a total pain. You have to know Javascript, CSS, JQuery, HTML, etc. There must be an easier way to develop data entry forms that produce the needed underlying code for a web page. Maybe I'm just not looking in the right place. There must be some WYSIWYG GUI development tools for the web for developing data entry forms out there. Anybody know of any?

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• Ralink RT3060 wireless device configuration on ubuntu 12.04

  - by Stephan

  concerning How do I get a Ralink RT3060 wireless card working? I'm running Ubuntu 12.04 with a 'LWPX07 Edimax EW-7711In 150M 1T1R WL PCI Card' which has a rt3060 chip. Out of the box the card is recognized as rt2800sta. I tried solution one, that didn't work. Still the card connects to the wireless network, but it seems to slow to load any pages. Then I tried solution 2, but then the network-manager doesn't see any wireless device. $ iwconfig lo no wireless extensions. ra0 Ralink STA Link Quality:0 Signal level:0 Noise level:0 Rx invalid nwid:0 invalid crypt:0 invalid misc:0 eth0 no wireless extensions. $ lsmod Module Size Used by rt3562sta 882296 0 $ lspci -v 05:02.0 Network controller: Ralink corp. RT3060 Wireless 802.11n 1T/1R Subsystem: Edimax Computer Co. Device 7711 Flags: bus master, slow devsel, latency 64, IRQ 23 Memory at ff9f0000 (32-bit, non-prefetchable) [size=64K] Capabilities: <access denied> Kernel driver in use: rt2860 Kernel modules: rt3562sta, rt2800pci Am I missing a configuration step? How do I tell the network card which driver to use? Thanks in advance Stephan I found the problem. As described in stevens blog http://steveswinsburg.wordpress.com/2011/03/12/how-to-install-a-d-link-dwa-525-wireless-network-card-in-ubuntu-10-04/ sudo su make && make install "You need to use ‘sudo su’ and not just ‘sudo’ so it creates the directories properly." That is the problem with the solution describe above.

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• Stereo images rectification and disparity: which algorithms?

  - by alessandro.francesconi

  I'm trying to figure out what are currently the two most efficent algorithms that permit, starting from a L/R pair of stereo images created using a traditional camera (so affected by some epipolar lines misalignment), to produce a pair of adjusted images plus their depth information by looking at their disparity. Actually I've found lots of papers about these two methods, like: "Computing Rectifying Homographies for Stereo Vision" (Zhang - seems one of the best for rectification only) "Three-step image recti?cation" (Monasse) "Rectification and Disparity" (slideshow by Navab) "A fast area-based stereo matching algorithm" (Di Stefano - seems a bit inaccurate) "Computing Visual Correspondence with Occlusions via Graph Cuts" (Kolmogorov - this one produces a very good disparity map, with also occlusion informations, but is it efficient?) "Dense Disparity Map Estimation Respecting Image Discontinuities" (Alvarez - toooo long for a first review) Anyone could please give me some advices for orienting into this wide topic? What kind of algorithm/method should I treat first, considering that I'll work on a very simple input: a pair of left and right images and nothing else, no more information (some papers are based on additional, pre-taken, calibration infos)? Speaking about working implementations, the only interesting results I've seen so far belongs to this piece of software, but only for automatic rectification, not disparity: http://stereo.jpn.org/eng/stphmkr/index.html I tried the "auto-adjustment" feature and seems really effective. Too bad there is no source code...

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• Best way to backup Xbox 360 USB Drive

  - by TekiusFanatikus

  What is the best way to backup/restore my USB drive that I use for my Xbox? I want to make sure that if the USB drive goes, that I can retrieve my saved games and such onto another USB drive. I was able to show the content of the drive, however, I wasn't sure if I could simply copy the content onto a Truecrypt volume and be able to restore it from there at a later date. The file system is not FAT or NTFS, wasn't sure about the impacts of copying from two different file systems... I currently have a DataTraveler G3 16GB. After a bit of googling, I was able to find this article, mentions an app called USBXtafGUI

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• PCI max throughput

  - by allentown

  Hypothetical here, but I want to understand. Say I have a hand me down machine, 4 PCI slots, 64-bit 33 MHz PCI. How much data can that PCI bus handle? System bus is 133 MHz. I want to use one slot for a SATA II card, and the rest for Gig-E cards, building out as fast a NAS as I can. I think one slot may be AGP2x, so that leaves me 2 for Gig-E and one for SATAT II. Will I saturate, what is the max bandwidth of the PCI bus?

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• Is an ACPI GPE storm normal in an Ubuntu session?

  - by Tinellus

  In a previous question (What is a an ACPI GPE storm?), I asked about ACPI GPE storm. Looking closer to my kern.log file in /var/log/, I notice that in every session at some point (usually withing 20' after startup) a GPE storm is triggered. When I open kern.log immediately after startup, I see that the 'GPE-storm' can be triggered by anything (a copy-action, the opening of an app like Firefox or Thunderbird, etc...). This worries me. Looking for other ACPI related events in kern.log, I find these error messages. I hope someone can give some advice: Jun 10 16:33:20 Guy-VAIO kernel: [ 0.724505] ACPI FADT declares the system doesn't support PCIe ASPM, so disable it Jun 10 16:33:20 Guy-VAIO kernel: [ 0.795205] [Firmware Bug]: ACPI: BIOS _OSI(Linux) query ignored Jun 10 16:33:20 Guy-VAIO kernel: [ 1.024009] ACPI: Deprecated procfs I/F for battery is loaded, please retry with CONFIG_ACPI_PROCFS_POWER cleared Jun 10 16:33:20 Guy-VAIO kernel: [ 23.140259] [Firmware Bug]: ACPI(VGA) defines _DOD but not _DOS There's also a video driver message that worries me, don't know if it's related though: Jun 10 16:33:20 Guy-VAIO kernel: [ 23.162154] fglrx: module license 'Proprietary. (C) 2002 - ATI Technologies, Starnberg, GERMANY' taints kernel. Jun 10 16:33:20 Guy-VAIO kernel: [ 23.162158] Disabling lock debugging due to kernel taint As mentioned in my previous question, I'm experiencing frequent (several times /d) application crashes, that seem random, with apport messages being sent, and less frequent (once a week or so) complete system freezes where the system becomes unresponsive to keyboard, mouse or touchpad input and the only solution is a hard reboot (press start button) My questions: what about the Firmware Bugs in ACPI? how and where do I have to 'clear CONFIG_ACPI_PROCFS_POWER'? what does it mean when fglrx 'taints the kernel', is it serious and what could I do about it? Ubuntu 12.04, 64-bit, 3.2.0-25-generic Kernel, Intel® Core™ i5-2430M CPU @ 2.40GHz × 4 Thanks

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• Functional programming and stateful algorithms

  - by bigstones

  I'm learning functional programming with Haskell. In the meantime I'm studying Automata theory and as the two seem to fit well together I'm writing a small library to play with automata. Here's the problem that made me ask the question. While studying a way to evaluate a state's reachability I got the idea that a simple recursive algorithm would be quite inefficient, because some paths might share some states and I might end up evaluating them more than once. For example, here, evaluating reachability of g from a, I'd have to exclude f both while checking the path through d and c: So my idea is that an algorithm working in parallel on many paths and updating a shared record of excluded states might be great, but that's too much for me. I've seen that in some simple recursion cases one can pass state as an argument, and that's what I have to do here, because I pass forward the list of states I've gone through to avoid loops. But is there a way to pass that list also backwards, like returning it in a tuple together with the boolean result of my canReach function? (although this feels a bit forced) Besides the validity of my example case, what other techniques are available to solve this kind of problems? I feel like these must be common enough that there have to be solutions like what happens with fold* or map. So far, reading learnyouahaskell.com I didn't find any, but consider I haven't touched monads yet. (if interested, I posted my code on codereview)

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