Search Results

Search found 8266 results on 331 pages for 'distributed systems'.

Page 300/331 | < Previous Page | 296 297 298 299 300 301 302 303 304 305 306 307  | Next Page >

• Should I choose KVM/XEN over OpenVZ or use them together?

  - by Krystian

  I've got a dual xeon e5504 server, with [for now] only 8GB of ram. Storage is'n impressive either: 3x 146GB sas in raid5 + 500GB sata drives. Currently it works as a development server, but it's over speced for our needs and since our development methods changed through last 2 years we decided it will work as a production system for some of our applications + we would like to have a separate system for testing/research. Our apps are mainly web apps deployed on tomcats [plural as some of the apps require older versions] and connected to Postgres. I would like to have a production system, where only httpd+tomcat+db are setup and nothing else runs there. Sterile system. Apart from that, I would like a test system, where I can play with different JVM settings, deploy my test apps, play with tomcat/httpd settings and restart them without interfering with the production system. Apart from that, I would like to be able to play with different linux flavors, with newer kernels to test how they work etc. I know, this is not possible with OpenVZ and I would have to choose KVM for that. I am thinking about merging the two, and setting up a KVM to be able to work with different systems [linux only to be frank] + use openVZ to setup separate machines for my development needs. I would simply go with that, but reading here and there about the performance impact full virtualization has over containers and looking at the specs of my server makes me think twice about it. I don't want to loose too much performance, especially because of the nature of my apps [few JVMs running at the same time]. It will be my first time with virtualization, apart from using desktop virtualbox/vmserver. Although I am a fast learner I don't want to mess with the main system so much that it will break the production apps or make them crawl. Although they are more or less internal apps and they don't produce much load, they need to be stable. I've read, that KVM host is a normal linux installation and it allows to run normal processes on it. If that is so, does it allow to run openVZ as well? I mean... can I have KVM and OpenVZ running on the same system/kernel? Or do I have to setup another system to run OpenVZ containers? How much performance impact can this have for me? Will my hardware suffice? oh and one more thing... unfortunately I'm quite limited with the funds... I'm looking for a free solution only :/

  Read the article

• Issue using a "used" SSD as a Windows 8.1 Boot Drive

  - by EpiGrad

  So, I'm something of a Mac person, but decided to take a stab at this whole "build yourself a PC" thing - right now, the thing is assembled, posts just fine, and can get to the BIOS. The problem is the drive I want to use - I intended to use a 80 GB Corsair SSD I've had sitting around as the boot drive, and a new Samsung SSD for games and the like. So I boot using a Windows 8.1 install USB stick, and if the Samsung drive is plugged in, it happily offers to install Windows on it. The Corsair drive though, it's flipped out - I reformatted it as a blank NTFS drive (it was HFS for Mac purposes) and the BIOS can't see it, nor can the Windows installer. What's wrong, and how do I fix it? The tools at my disposal are: The current ASUS BIOS that came with my motherboard (a Z87I-Deluxe), a Mac running the latest OS X which can also boot to Windows 7 if needed via either Parallels or Bootcamp. Update 1: Update: Based on a friend's suggestion to switch SATA ports, Windows 8.1's installer can now see the drive as Drive 0, Partition 1, a 83.8 GB "Primary" partition. But when I click it and hit "Next", I get the following error: "We couldn't create a new partition or locate an existing one. For more information, see the Setup log files" - not that it gives any clue how to access those. Update 2: Following a trail of Google suggestions, I ended up going into advanced tools and just reformatting the drive as follows: Start DISKPART. Type LIST DISK and identify your SSD disk number (from 0 to n disks). Type SELECT DISK <n> where <n> is your SSD disk number. Type CLEAN Type CREATE PARTITION PRIMARY Type ACTIVE Type FORMAT FS=NTFS QUICK Type ASSIGN Type EXIT twice (one to get out of DiskPart, the other to exit the command line tool) Per these instructions. This goes well enough, but now I can select the disk for installation, and I get a new error: "Windows 8 cannot be installed to this disk. The selected disk has an MBR partition table. On EFI systems, Windows can only be installed to GP disks." So, Googling that, I do the following: select disk 0 clean convert gpt exit ...and we might have fixed it. Windows is at least trying to install now.

  Read the article

• Achieving A 1600 x 900 Resolution For (Guest OS) Ubuntu Under (Host OS) Windows 7

  - by panamack

  I am running Ubuntu 11.10 as a guest OS using VirtualBox 4.1.16 installed on Windows 7 Ultimate. On my laptop I'd like to be able to run Ubuntu in full screen mode at 1600 x 900. I only have options within the virtual machine to select 4:3 display settings such as 1600 x 1200, 1440 x 1050 etc. I have guest additions installed. At the windows command prompt, I tried typing: VBoxManage setextradata "Virtual Ubuntu Coursera ESSAAS" "CustomVideoMode1" "1600x900x16" This didn't work, still no 1600 x 900 res available in Ubuntu. I tried this having read the following section of the VirtualBox help (this also says something about a 'video mode hint feature' not sure what this means): 9.7. Advanced display configuration 9.7.1. Custom VESA resolutions Apart from the standard VESA resolutions, the VirtualBox VESA BIOS allows you to add up to 16 custom video modes which will be reported to the guest operating system. When using Windows guests with the VirtualBox Guest Additions, a custom graphics driver will be used instead of the fallback VESA solution so this information does not apply. Additional video modes can be configured for each VM using the extra data facility. The extra data key is called CustomVideoMode with x being a number from 1 to 16. Please note that modes will be read from 1 until either the following number is not defined or 16 is reached. The following example adds a video mode that corresponds to the native display resolution of many notebook computers: VBoxManage setextradata "VM name" "CustomVideoMode1" "1400x1050x16" The VESA mode IDs for custom video modes start at 0x160. In order to use the above defined custom video mode, the following command line has be supplied to Linux: vga = 0x200 | 0x160 vga = 864 For guest operating systems with VirtualBox Guest Additions, a custom video mode can be set using the video mode hint feature. UPDATE 02.06.12 I've just tried creating a new virtual machine using the same original disk image I had been given. This had Guest Additions v 4.1.6 installed and provided me with the 1600 x 900 full screen display I want. It's after I then install Guest Additions v 4.1.16 (the version included with my VirtualBox installation) that my only choices are 4:3 displays e.g. 1600 x 1200. Seems this is the cause.

  Read the article

• FTP script needs blank line

  - by Ones and Zeroes

  I am trying to determine the reason for some FTP servers requiring a blank line in the script as follows: open server.com username ftp_commands bye Refer to blank line required after username credentials. Example from: FTP from batch file another reference to the same: http://newsgroups.derkeiler.com/Archive/Comp/comp.sys.ibm.as400.misc/2008-05/msg00227.html Also discussed here: archive.midrange.com/midrange-l/200601/msg00048.html "The behavior I'm observing is the same as if I didn't specify the password to login." with an answer referring to our same fix... archive.midrange.com/midrange-l/200601/msg00053.html and archive.midrange.com/midrange-l/200601/msg00065.html Note: It is my experience that FTP questions attract uncouth responses. Admittedly FTP is outdated, but many clients still have legacy systems, which they cannot upgrade or replace. The reason thereof should not be discussed here. The intention of this question is to invite a positive response. Please do not respond if you disagree with the above. If you have never encountered this same issue, please do not respond. I suspect this may be limited to FTP scripts executed from Windows machines, but have been told that this happens often and with many different servers. My specific interest is to understand what may cause this as I have a real world example of a production system suddenly requiring this as a workaround fix, after running for many years without issue. The server belongs to a third party who claims no change on their end. Server details unknown and cannot be determined. Any help or encouragement from someone who has come across the same, would be appreciated. ps. Sorry for the many words and references to painful responses, but I have asked similar questions on serverfault and elsewhere and unfortunately got back kneejerk responses to FTP and respondents debating the validity of the question. I would truly not ask, or re-post this question online if I had a better understanding of the issue. I know of people who have seen this issue, but don't know what causes it. I am wary that this question would again turn into another irrelevant discussion. Please, I ask very nicely: Please do not respond if you have not encountered a similar issue. FURTHER EDIT: Please do not suggest changing the product. The problem is not the blank line requirement. We know this fixes the issue. The problem is not being able to explain the reason for the blank line in the first place. Slight difference, but a critical point to note wrt the answering of this question.

  Read the article

• How to make Nginx fire 504 immediately is server is not available?

  - by Georgiy Ivankin

  I have Nginx set up as a load balancer with cookie-based stickiness. The logic is: If the cookie is NOT there, use round-robbing to choose a server from cluster. If the cookie is there, go to the server that is associated with the cookie value. Server is then responsible for setting the cookie. What I want to add is this: If the cookie is there, but server is down, fallback to round-robbing step to choose next available server. So actually I have load balancing and want to add failover support on top of it. I have managed to do that with the help of error_page directive, but it doesn't work as I expected it to. The problem: 504 (and the fallback associated with it) fires only after 30s timeout even if the server is not physically available. So what I want Nginx to do is fire a 504 (or any other error, doesn't matter) immediately (I suppose this means: when TCP connection fails). This is the behavior we can see in browsers: if we go directly to server when it is down, browser immediately tells us that it can't connect. Moreover, Nginx seems to be doing this for 502 error: if I intentionally misconfigure my servers, Nginx fires 502 immediately. Configuration (stripped down to basics): http { upstream my_cluster { server 192.168.73.210:1337; server 192.168.73.210:1338; } map $cookie_myCookie $http_sticky_backend { default 0; value1 192.168.73.210:1337; value2 192.168.73.210:1338; } server { listen 8080; location @fallback { proxy_pass http://my_cluster; } location / { error_page 504 = @fallback; # Create a map of choices # see https://gist.github.com/jrom/1760790 set $test HTTP; if ($http_sticky_backend) { set $test "${test}-STICKY"; } if ($test = HTTP-STICKY) { proxy_pass http://$http_sticky_backend$uri?$args; break; } if ($test = HTTP) { proxy_pass http://my_cluster; break; } return 500 "Misconfiguration"; } } } Disclaimer: I am pretty far from systems administration of any kind, so there may be some basics that I miss here. EDIT: I'm interested in solution with standard free version of Nginx, not Nginx Plus. Thanks.

  Read the article

• Wrapping a point-to-point link

  - by user3712955

  I'm using a pair of IP radios (non-WiFi) to bridge my office engineering LAN (172.0.0.0/8) to a lab in another building. The radios work fine, but they expose a web management interface I'd like to hide, and they also generate traffic (ARP, STP, and more) that I need to keep off my (very, very clean) LAN segments. I have some ARM-Linux boards (similar to Beagle/Panda/RasPi) running Ubuntu, and I've put one at each end of the link, between the radio and the LAN. Each of the boards has 2 wired Ethernet interfaces, eth0 and eth1. The LAN segments are connected to eth0, and the radios are connected to eth1. I'd like to accomplish the following: Keep radio-originated traffic off my LAN segments! Hide all services provided by the radio (web, ssh, etc.) Transparently pass all traffic between the LAN segments (including things like ARP). The above also applies to the ARM-Linux boards: No stray traffic my LAN from them either! I'd like the system to look like a switch: LAN packets arriving at one eth0 appear at the other. And neither eth0 should have an IP address: The working system should behave like a CAT6 cable with some latency (instead of ARM boards and radios). Unfortunately, I'm confused about how to properly configure the ARM Ubuntu systems. What I'm guessing I need is a bridge on each board (br0?) and a VLAN (vlan0 or eth0.0?) to isolate the LAN traffic from everything else as it passes through the ARM boards and the radios. Then I need some kind of a firewall to block sending anything out eth0 that isn't from the other eth0 (via the VLAN). I've looked at the ip and ebtables commands (especially -t broute). While the concepts sorta-kinda make sense, I'm completely lost in the details. Edit: In the perverse case that a system on one of my LAN segments has the same IP address as one of the radios, or as eth1 on the ARM-Ubuntu boards, a VLAN won't work. Which I believe means I need to tunnel all traffic between the two eth0 interfaces to get that "like a wire" behavior. Help? Finally, I'd like to have a way to temporarily expose services on the ARM boards (ssh) and the radios (web) for maintenance purposes. Ideally, it would expose an IP address with ssh available on port 22. Once connected, I figure I'd start an X11 session and run a browser on the ARM board to access the radios. Or something. I could login via the console to enable/disable this, or perhaps could use a GPIO to trigger a script. I feel I've identified most of the pieces needed to make all this happen, but I have no idea how to combine them to make a working system. Thanks!

  Read the article

• Migrating Split Access Database from one domain to another (not working, details in Q)

  - by Expo_Rob

  Some background: I'm a programmer, not a network administrator, who has been asked to migrate some accounting software (Integrated Office Accounting version 3.2) from an existing domain (OLD_NETWORK) to a new domain (NEW_NETWORK). No-body at the office knows how it works under the hood. It is a split Access 2000 database with the back-end shared and on a file server (which is also the DC) using mapped drives. The DC is NT Server 4 SP 6. The new server is server 2003. The two networks are running independently (ie: two computers on each desk). I have been able to get new computers set up on NEW_NETWORK and working with the IOA software just perfectly but for one problem: The company here uses other entirely separate databases which access the tables IOA maintains (specifically the 'customers' table) via links. To switch between these systems, you press F11 then File-Open the appropriate database and away you go (this is necessary to maintain the permissions that the IOA system uses to protect the customers table). The entire database is Access 2000, the links go to other Access databases, SQL-Server is not involved in any way, nor is a migration to SQL server likely. If I can't migrate anything over, everything will stay as it is, and the NEW_NETWORK computers will not be used. The problem: When I try and update these seperate databases (I shall call one "BANK_ACCOUNT", but the name does not matter), it says "this recordset cannot be updated". It also will sometimes not pull information out of the 'customers' table (ie: date_entered) when looking at a report of everyone who opened a bank account on a certain day (ie: today). I have tried: Giving 'everyone' full control via. shared directory permissions Giving 'everyone' full control on a file system level Checking the permissions within Access (everyone has full read/write on all tables) Copying the entire server contents from one file server to another (ie: xcopy everything) Copying the entire local client files from one computer to another, putting them in the exact same position in the file system, with the same permissons (or full control to 'everyone'). Running as an Administrator Taking one of the NEW_NETWORK computers, having it join OLD_NETWORK and run the software (direct copy from a working system with identical drive mappings), this did not work Weeping openly My Question: Is there anything else I can try? (sorry for this being so long)

  Read the article

• Git for beginners: The definitive practical guide

  - by Adam Davis

  Ok, after seeing this post by PJ Hyett, I have decided to skip to the end and go with git. So what I need is a beginners practical guide to git. "Beginner" being defined as someone who knows how to handle their compiler, understands to some level what a makefile is, and has touched source control without understanding it very well. "Practical" being defined as this person doesn't want to get into great detail regarding what git is doing in the background, and doesn't even care (or know) that it's distributed. Your answers might hint at the possibilities, but try to aim for the beginner that wants to keep a 'main' repository on a 'server' which is backed up and secure, and treat their local repository as merely a 'client' resource. Procedural note: PLEASE pick one and only one of the below topics and answer it clearly and concisely in any given answer. Don't try to jam a bunch of information into one answer. Don't just link to other resources - cut and paste with attribution if copyright allows, otherwise learn it and explain it in your own words (ie, don't make people leave this page to learn a task). Please comment on, or edit, an already existing answer unless your explanation is very different and you think the community is better served with a different explanation rather than altering the existing explanation. So: Installation/Setup How to install git How do you set up git? Try to cover linux, windows, mac, think 'client/server' mindset. Setup GIT Server with Msysgit on Windows How do you create a new project/repository? How do you configure it to ignore files (.obj, .user, etc) that are not really part of the codebase? Working with the code How do you get the latest code? How do you check out code? How do you commit changes? How do you see what's uncommitted, or the status of your current codebase? How do you destroy unwanted commits? How do you compare two revisions of a file, or your current file and a previous revision? How do you see the history of revisions to a file? How do you handle binary files (visio docs, for instance, or compiler environments)? How do you merge files changed at the "same time"? How do you undo (revert or reset) a commit? Tagging, branching, releases, baselines How do you 'mark' 'tag' or 'release' a particular set of revisions for a particular set of files so you can always pull that one later? How do you pull a particular 'release'? How do you branch? How do you merge branches? How do you resolve conflicts and complete the merge? How do you merge parts of one branch into another branch? What is rebasing? How do I track remote branches? How can I create a branch on a remote repository? Other Describe and link to a good gui, IDE plugin, etc that makes git a non-command line resource, but please list its limitations as well as its good. msysgit - Cross platform, included with git gitk - Cross platform history viewer, included with git gitnub - OS X gitx - OS X history viewer smartgit - Cross platform, commercial, beta tig - console GUI for Linux qgit - GUI for Windows, Linux Any other common tasks a beginner should know? Git Status tells you what you just did, what branch you have, and other useful information How do I work effectively with a subversion repository set as my source control source? Other git beginner's references git guide git book git magic gitcasts github guides git tutorial Progit - book by Scott Chacon Git - SVN Crash Course Delving into git Understanding git conceptually I will go through the entries from time to time and 'tidy' them up so they have a consistent look/feel and it's easy to scan the list - feel free to follow a simple "header - brief explanation - list of instructions - gotchas and extra info" template. I'll also link to the entries from the bullet list above so it's easy to find them later.

  Read the article

• no namenode error in pseudo-mode

  - by Anshu Basia

  I'm new to hadoop and is in learning phase. As per Hadoop Definitve guide, i have set up my hadoop in pseudo distributed mode and everything was working fine. I was even able to execute all the examples from chapter 3 yesterday. Today, when i rebooted my unix and tried to run start-dfs.sh and then tried http://localhost/50070....it is showing error and when i try to stop dfs (stop-dfs.sh) it says no namenode to stop. I have been googling the issue but no result. Also, when i format my namenode again...everything starts working fine and i'm able to connect to the localhost/50070 and even replicate files and directories in hdfs but as soon as i restart my linux and try to connect to hdfs the same problem comes up. Below is the error log: ************************************************************/ 2011-06-22 15:45:55,249 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: STARTUP_MSG: /************************************************************ STARTUP_MSG: Starting NameNode STARTUP_MSG: host = ubuntu/127.0.1.1 STARTUP_MSG: args = [] STARTUP_MSG: version = 0.20.203.0 STARTUP_MSG: build = http://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20-security-203 -r 1099333; compiled by 'oom' on Wed May 4 07:57:50 PDT 2011 ************************************************************/ 2011-06-22 15:45:56,383 INFO org.apache.hadoop.metrics2.impl.MetricsConfig: loaded properties from hadoop-metrics2.properties 2011-06-22 15:45:56,455 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source MetricsSystem,sub=Stats registered. 2011-06-22 15:45:56,494 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Scheduled snapshot period at 10 second(s). 2011-06-22 15:45:56,494 INFO org.apache.hadoop.metrics2.impl.MetricsSystemImpl: NameNode metrics system started 2011-06-22 15:45:57,007 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source ugi registered. 2011-06-22 15:45:57,031 WARN org.apache.hadoop.metrics2.impl.MetricsSystemImpl: Source name ugi already exists! 2011-06-22 15:45:57,059 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source jvm registered. 2011-06-22 15:45:57,070 INFO org.apache.hadoop.metrics2.impl.MetricsSourceAdapter: MBean for source NameNode registered. 2011-06-22 15:45:57,374 INFO org.apache.hadoop.hdfs.util.GSet: VM type = 32-bit 2011-06-22 15:45:57,374 INFO org.apache.hadoop.hdfs.util.GSet: 2% max memory = 19.33375 MB 2011-06-22 15:45:57,374 INFO org.apache.hadoop.hdfs.util.GSet: capacity = 2^22 = 4194304 entries 2011-06-22 15:45:57,374 INFO org.apache.hadoop.hdfs.util.GSet: recommended=4194304, actual=4194304 2011-06-22 15:45:57,854 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: fsOwner=anshu 2011-06-22 15:45:57,854 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: supergroup=supergroup 2011-06-22 15:45:57,854 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: isPermissionEnabled=true 2011-06-22 15:45:57,868 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: dfs.block.invalidate.limit=100 2011-06-22 15:45:57,869 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: isAccessTokenEnabled=false accessKeyUpdateInterval=0 min(s), accessTokenLifetime=0 min(s) 2011-06-22 15:45:58,769 INFO org.apache.hadoop.hdfs.server.namenode.FSNamesystem: Registered FSNamesystemStateMBean and NameNodeMXBean 2011-06-22 15:45:58,809 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: Caching file names occuring more than 10 times **2011-06-22 15:45:58,825 INFO org.apache.hadoop.hdfs.server.common.Storage: Storage directory /tmp/hadoop-anshu/dfs/name does not exist. 2011-06-22 15:45:58,827 ERROR org.apache.hadoop.hdfs.server.namenode.FSNamesystem: FSNamesystem initialization failed. org.apache.hadoop.hdfs.server.common.InconsistentFSStateException: Directory /tmp/hadoop-anshu/dfs/name is in an inconsistent state: storage directory does not exist or is not accessible. at org.apache.h**adoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:291) at org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:97) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:379) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:353) at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:254) at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:434) at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1153) at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1162) 2011-06-22 15:45:58,828 ERROR org.apache.hadoop.hdfs.server.namenode.NameNode: org.apache.hadoop.hdfs.server.common.InconsistentFSStateException: Directory /tmp/hadoop-anshu/dfs/name is in an inconsistent state: storage directory does not exist or is not accessible. at org.apache.hadoop.hdfs.server.namenode.FSImage.recoverTransitionRead(FSImage.java:291) at org.apache.hadoop.hdfs.server.namenode.FSDirectory.loadFSImage(FSDirectory.java:97) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.initialize(FSNamesystem.java:379) at org.apache.hadoop.hdfs.server.namenode.FSNamesystem.<init>(FSNamesystem.java:353) at org.apache.hadoop.hdfs.server.namenode.NameNode.initialize(NameNode.java:254) at org.apache.hadoop.hdfs.server.namenode.NameNode.<init>(NameNode.java:434) at org.apache.hadoop.hdfs.server.namenode.NameNode.createNameNode(NameNode.java:1153) at org.apache.hadoop.hdfs.server.namenode.NameNode.main(NameNode.java:1162) 2011-06-22 15:45:58,829 INFO org.apache.hadoop.hdfs.server.namenode.NameNode: SHUTDOWN_MSG: /************************************************************ SHUTDOWN_MSG: Shutting down NameNode at ubuntu/127.0.1.1 ************************************************************/ Any help is appreciated Thank-you

  Read the article

• What is the reason of "Transaction context in use by another session"

  - by Shrike

  Hi, I'm looking for a description of the root of this error: "Transaction context in use by another session". I get it sometimes in one of my unittests so I can't provider repro code. But I wonder what is "by design" reason for the error. I've found this post: http://blogs.msdn.com/asiatech/archive/2009/08/10/system-transaction-may-fail-in-multiple-thread-environment.aspx and also that: http://msdn.microsoft.com/en-us/library/ff649002.aspx But I can't understand what "Multiple threads sharing the same transaction in a transaction scope will cause the following exception: 'Transaction context in use by another session.' " means. All words are understandable but not the point. I actually can share a system transaction between threads. And there is even special mechanism for this - DependentTransaction class and Transaction.DependentClone method. I'm trying to reproduce a usecase from the first post: 1. Main thread creates DTC transaction, receives DependentTransaction (created using Transaction.Current.DependentClone on the main thread 2. Child thread 1 enlists in this DTC transaction by creating a transaction scope based on the dependent transaction (passed via constructor) 3. Child thread 1 opens a connection 4. Child thread 2 enlists in DTC transaction by creating a transaction scope based on the dependent transaction (passed via constructor) 5. Child thread 2 opens a connection with such code: using System; using System.Threading; using System.Transactions; using System.Data; using System.Data.SqlClient; public class Program { private static string ConnectionString = "Initial Catalog=DB;Data Source=.;User ID=user;PWD=pwd;"; public static void Main() { int MAX = 100; for(int i =0; i< MAX;i++) { using(var ctx = new TransactionScope()) { var tx = Transaction.Current; // make the transaction distributed using (SqlConnection con1 = new SqlConnection(ConnectionString)) using (SqlConnection con2 = new SqlConnection(ConnectionString)) { con1.Open(); con2.Open(); } showSysTranStatus(); DependentTransaction dtx = Transaction.Current.DependentClone(DependentCloneOption.BlockCommitUntilComplete); Thread t1 = new Thread(o => workCallback(dtx)); Thread t2 = new Thread(o => workCallback(dtx)); t1.Start(); t2.Start(); t1.Join(); t2.Join(); ctx.Complete(); } trace("root transaction completes"); } } private static void workCallback(DependentTransaction dtx) { using(var txScope1 = new TransactionScope(dtx)) { using (SqlConnection con2 = new SqlConnection(ConnectionString)) { con2.Open(); trace("connection opened"); showDbTranStatus(con2); } txScope1.Complete(); } trace("dependant tran completes"); } private static void trace(string msg) { Console.WriteLine(Thread.CurrentThread.ManagedThreadId + " : " + msg); } private static void showSysTranStatus() { string msg; if (Transaction.Current != null) msg = Transaction.Current.TransactionInformation.DistributedIdentifier.ToString(); else msg = "no sys tran"; trace( msg ); } private static void showDbTranStatus(SqlConnection con) { var cmd = con.CreateCommand(); cmd.CommandText = "SELECT 1"; var c = cmd.ExecuteScalar(); trace("@@TRANCOUNT = " + c); } } It fails on Complete's call of root TransactionScope. But error is different: Unhandled Exception: System.Transactions.TransactionInDoubtException: The transaction is in doubt. --- pired. The timeout period elapsed prior to completion of the operation or the server is not responding. To sum up: I want to understand what "Transaction context in use by another session" means and how to reproduce it.

  Read the article

• Oracle performance problem

  - by jreid42

  We are using an Oracle 11G machine that is very powerful; has redundant storage etc. It's a beast from what I have been told. We just got this DB for a tool that when I first came on as a coop had like 20 people using, now its upwards of 150 people. I am the only one working on it :( We currently have a system in place that distributes PERL scripts across our entire data center essentially giving us a sort of "grid" computing power. The Perl scripts run a sort of simulation and report back the results to the database. They do selects / inserts. The load is not very high for each script but it could be happening across 20-50 systems at the same time. We then have multiple data centers and users all hitting the same database with this same approach. Our main problem with this is that our database is getting overloaded with connections and having to drop some. We sometimes have upwards of 500 connections. These are old perl scripts and they do not handle this well. Essentially they fail and the results are lost. I would rather avoid having to rewrite a lot of these as they are poorly written, and are a headache to even look at. The database itself is not overloaded, just the connection overhead is too high. We open a connection, make a quick query and then drop the connection. Very short connections but many of them. The database team has basically said we need to lower the number of connections or they are going to ignore us. Because this is distributed across our farm we cant implement persistent connections. I do this with our webserver; but its on a fixed system. The other ones are perl scripts that get opened and closed by the distribution tool and thus arent always running. What would be my best approach to resolving this issue? The scripts themselves can wait for a connection to be open. They do not need to act immediately. Some sort of queing system? I've been suggested to set up a few instances of a tool called "SQL Relay". Maybe one in each data center. How reliable is this tool? How good is this approach? Would it work for what we need? We could have one for each data center and relay requests through it to our main database, keeping a pipeline of open persistent connections? Does this make sense? Is there any other suggestions you can make? Any ideas? Any help would be greatly appreciated. Sadly I am just a coop student working for a very big company and somehow all of this has landed all on my shoulders (there is literally nobody to ask for help; its a hardware company, everybody is hardware engineers, and the database team is useless and in India) and I am quite lost as what the best approach would be? I am extremely overworked and this problem is interfering with on going progress and basically needs to be resolved as quickly as possible; preferably without rewriting the whole system, purchasing hardware (not gonna happen), or shooting myself in the foot. HELP LOL!

  Read the article

• Thinking Sphinx not working in test mode

  - by J. Pablo Fernández

  I'm trying to get Thinking Sphinx to work in test mode in Rails. Basically this: ThinkingSphinx::Test.init ThinkingSphinx::Test.start freezes and never comes back. My test and devel configuration is the same for test and devel: dry_setting: &dry_setting adapter: mysql host: localhost encoding: utf8 username: rails password: blahblah development: <<: *dry_setting database: proj_devel socket: /tmp/mysql.sock # sphinx requires it test: <<: *dry_setting database: proj_test socket: /tmp/mysql.sock # sphinx requires it and sphinx.yml development: enable_star: 1 min_infix_len: 2 bin_path: /opt/local/bin test: enable_star: 1 min_infix_len: 2 bin_path: /opt/local/bin production: enable_star: 1 min_infix_len: 2 The generated config files, config/development.sphinx.conf and config/test.sphinx.conf only differ in database names, directories and similar things; nothing functional. Generating the index for devel goes without an issue $ rake ts:in (in /Users/pupeno/proj) default config Generating Configuration to /Users/pupeno/proj/config/development.sphinx.conf Sphinx 0.9.8.1-release (r1533) Copyright (c) 2001-2008, Andrew Aksyonoff using config file '/Users/pupeno/proj/config/development.sphinx.conf'... indexing index 'user_core'... collected 7 docs, 0.0 MB collected 0 attr values sorted 0.0 Mvalues, 100.0% done sorted 0.0 Mhits, 99.8% done total 7 docs, 422 bytes total 0.098 sec, 4320.80 bytes/sec, 71.67 docs/sec indexing index 'user_delta'... collected 0 docs, 0.0 MB collected 0 attr values sorted 0.0 Mvalues, nan% done total 0 docs, 0 bytes total 0.010 sec, 0.00 bytes/sec, 0.00 docs/sec distributed index 'user' can not be directly indexed; skipping. but when I try to do it for test it freezes: $ RAILS_ENV=test rake ts:in (in /Users/pupeno/proj) DEPRECATION WARNING: require "activeresource" is deprecated and will be removed in Rails 3. Use require "active_resource" instead.. (called from /Users/pupeno/.rvm/gems/ruby-1.8.7-p249/gems/activeresource-2.3.5/lib/activeresource.rb:2) default config Generating Configuration to /Users/pupeno/proj/config/test.sphinx.conf Sphinx 0.9.8.1-release (r1533) Copyright (c) 2001-2008, Andrew Aksyonoff using config file '/Users/pupeno/proj/config/test.sphinx.conf'... indexing index 'user_core'... It's been there for more than 10 minutes, the user table has 4 records. The database directory look quite diferently, but I don't know what to make of it: $ ls -l db/sphinx/development/ total 96 -rw-r--r-- 1 pupeno staff 196 Mar 11 18:10 user_core.spa -rw-r--r-- 1 pupeno staff 4982 Mar 11 18:10 user_core.spd -rw-r--r-- 1 pupeno staff 417 Mar 11 18:10 user_core.sph -rw-r--r-- 1 pupeno staff 3067 Mar 11 18:10 user_core.spi -rw-r--r-- 1 pupeno staff 84 Mar 11 18:10 user_core.spm -rw-r--r-- 1 pupeno staff 6832 Mar 11 18:10 user_core.spp -rw-r--r-- 1 pupeno staff 0 Mar 11 18:10 user_delta.spa -rw-r--r-- 1 pupeno staff 1 Mar 11 18:10 user_delta.spd -rw-r--r-- 1 pupeno staff 417 Mar 11 18:10 user_delta.sph -rw-r--r-- 1 pupeno staff 1 Mar 11 18:10 user_delta.spi -rw-r--r-- 1 pupeno staff 0 Mar 11 18:10 user_delta.spm -rw-r--r-- 1 pupeno staff 1 Mar 11 18:10 user_delta.spp $ ls -l db/sphinx/test/ total 0 -rw-r--r-- 1 pupeno staff 0 Mar 11 18:11 user_core.spl -rw-r--r-- 1 pupeno staff 0 Mar 11 18:11 user_core.tmp0 -rw-r--r-- 1 pupeno staff 0 Mar 11 18:11 user_core.tmp1 -rw-r--r-- 1 pupeno staff 0 Mar 11 18:11 user_core.tmp2 -rw-r--r-- 1 pupeno staff 0 Mar 11 18:11 user_core.tmp7 Nothing gets added to a log when this happens. Any ideas where to go from here? I can run the command line manually: /opt/local/bin/indexer --config config/test.sphinx.conf --all which generates the output as the rake ts:in, so no help there.

  Read the article

• Quartz Thread Execution Parallel or Sequential?

  - by vikas

  We have a quartz based scheduler application which runs about 1000 jobs per minute which are evenly distributed across seconds of each minute i.e. about 16-17 jobs per second. Ideally, these 16-17 jobs should fire at same time, however our first statement, which simply logs the time of execution, of execute method of the job is being called very late. e.g. let us assume we have 1000 jobs scheduled per minute from 05:00 to 05:04. So, ideally the job which is scheduled at 05:03:50 should have logged the first statement of the execute method at 05:03:50, however, it is doing it at about 05:06:38. I have tracked down the time taken by the scheduled job which comes around 15-20 milliseconds. This scheduled job is fast enough because we just send a message on an ActiveMQ queue. We have specified the number of threads of quartz to be 100 and even tried with increasing it to 200 and more, but no gain. One more thing we noticed is that logs from scheduler are coming sequential after first 1 minute i.e. [Quartz_Worker_28] <Some log statement> .. .. [Quartz_Worker_29] <Some log statement> .. .. [Quartz_Worker_30] <Some log statement> .. .. So it suggesting that after some time quartz is running threads almost sequential. May be this is happening due to the time taken in notifying the job completion to persistence store (which is a separate postgres database in this case) and/or context switching. What can be the reason behind this strange behavior? EDIT: More detailed Log [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] org.quartz.plugins.history.LoggingTriggerHistoryPlugin - Trigger [<trigger_name>] fired job [<job_name>] scheduled at: 06-07-2012 10:08:33.458, next scheduled at: 06-07-2012 10:34:53.000 [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob - execute begin--------- ScheduledLocateJob with key: <job_name> started at Fri Jul 06 10:08:37 EDT 2012 [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob <some log statement> [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob <some log statement> [06/07/12 10:08:37:192][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob <some log statement> [06/07/12 10:08:37:220][QuartzScheduler_Worker-34][INFO] <my_package>.scheduler.quartz.ScheduledLocateJob - execute end--------- ScheduledLocateJob with key: <job_name> ended at Fri Jul 06 10:08:37 EDT 2012 [06/07/12 10:08:37:220][QuartzScheduler_Worker-34][INFO] org.quartz.plugins.history.LoggingTriggerHistoryPlugin - Trigger [<trigger_name>] completed firing job [<job_name>] with resulting trigger instruction code: DO NOTHING. Next scheduled at: 06-07-2012 10:34:53.000 I am doubting on this section of the above log scheduled at: 06-07-2012 10:08:33.458, next scheduled at: 06-07-2012 10:34:53.000 because this job was scheduled for 10:04:53, but it fired at 10:08:33 and still quartz didn't consider it as misfire. Shouldn't it be a misfire?

  Read the article

• Python dictionary key missing

  - by Greg K

  I thought I'd put together a quick script to consolidate the CSS rules I have distributed across multiple CSS files, then I can minify it. I'm new to Python but figured this would be a good exercise to try a new language. My main loop isn't parsing the CSS as I thought it would. I populate a list with selectors parsed from the CSS files to return the CSS rules in order. Later in the script, the list contains an element that is not found in the dictionary. for line in self.file.readlines(): if self.hasSelector(line): selector = self.getSelector(line) if selector not in self.order: self.order.append(selector) elif selector and self.hasProperty(line): # rules.setdefault(selector,[]).append(self.getProperty(line)) property = self.getProperty(line) properties = [] if selector not in rules else rules[selector] if property not in properties: properties.append(property) rules[selector] = properties # print "%s :: %s" % (selector, "".join(rules[selector])) return rules Error encountered: $ css-combine combined.css test1.css test2.css Traceback (most recent call last): File "css-combine", line 108, in <module> c.run(outfile, stylesheets) File "css-combine", line 64, in run [(selector, rules[selector]) for selector in parser.order], KeyError: 'p' Swap the inputs: $ css-combine combined.css test2.css test1.css Traceback (most recent call last): File "css-combine", line 108, in <module> c.run(outfile, stylesheets) File "css-combine", line 64, in run [(selector, rules[selector]) for selector in parser.order], KeyError: '#header_.title' I've done some quirky things in the code like sub spaces for underscores in dictionary key names in case it was an issue - maybe this is a benign precaution? Depending on the order of the inputs, a different key cannot be found in the dictionary. The script: #!/usr/bin/env python import optparse import re class CssParser: def __init__(self): self.file = False self.order = [] # store rules assignment order def parse(self, rules = {}): if self.file == False: raise IOError("No file to parse") selector = False for line in self.file.readlines(): if self.hasSelector(line): selector = self.getSelector(line) if selector not in self.order: self.order.append(selector) elif selector and self.hasProperty(line): # rules.setdefault(selector,[]).append(self.getProperty(line)) property = self.getProperty(line) properties = [] if selector not in rules else rules[selector] if property not in properties: properties.append(property) rules[selector] = properties # print "%s :: %s" % (selector, "".join(rules[selector])) return rules def hasSelector(self, line): return True if re.search("^([#a-z,\.:\s]+){", line) else False def getSelector(self, line): s = re.search("^([#a-z,:\.\s]+){", line).group(1) return "_".join(s.strip().split()) def hasProperty(self, line): return True if re.search("^\s?[a-z-]+:[^;]+;", line) else False def getProperty(self, line): return re.search("([a-z-]+:[^;]+;)", line).group(1) class Consolidator: """Class to consolidate CSS rule attributes""" def run(self, outfile, files): parser = CssParser() rules = {} for file in files: try: parser.file = open(file) rules = parser.parse(rules) except IOError: print "Cannot read file: " + file finally: parser.file.close() self.serialize( [(selector, rules[selector]) for selector in parser.order], outfile ) def serialize(self, rules, outfile): try: f = open(outfile, "w") for rule in rules: f.write( "%s {\n\t%s\n}\n\n" % ( " ".join(rule[0].split("_")), "\n\t".join(rule[1]) ) ) except IOError: print "Cannot write output to: " + outfile finally: f.close() def init(): op = optparse.OptionParser( usage="Usage: %prog [options] <output file> <stylesheet1> " + "<stylesheet2> ... <stylesheetN>", description="Combine CSS rules spread across multiple " + "stylesheets into a single file" ) opts, args = op.parse_args() if len(args) < 3: if len(args) == 1: print "Error: No input files specified.\n" elif len(args) == 2: print "Error: One input file specified, nothing to combine.\n" op.print_help(); exit(-1) return [opts, args] if __name__ == '__main__': opts, args = init() outfile, stylesheets = [args[0], args[1:]] c = Consolidator() c.run(outfile, stylesheets) Test CSS file 1: body { background-color: #e7e7e7; } p { margin: 1em 0em; } File 2: body { font-size: 16px; } #header .title { font-family: Tahoma, Geneva, sans-serif; font-size: 1.9em; } #header .title a, #header .title a:hover { color: #f5f5f5; border-bottom: none; text-shadow: 2px 2px 3px rgba(0, 0, 0, 1); } Thanks in advance.

  Read the article

• I don't understand how work call_once

  - by SABROG

  Please help me understand how work call_once Here is thread-safe code. I don't understand why this need Thread Local Storage and global_epoch variables. Variable _fast_pthread_once_per_thread_epoch can be changed to constant/enum like {FAST_PTHREAD_ONCE_INIT, BEING_INITIALIZED, FINISH_INITIALIZED}. Why needed count calls in global_epoch? I think this code can be rewriting with logc: if flag FINISH_INITIALIZED do nothing, else go to block with mutexes and this all. #ifndef FAST_PTHREAD_ONCE_H #define FAST_PTHREAD_ONCE_H #include #include typedef sig_atomic_t fast_pthread_once_t; #define FAST_PTHREAD_ONCE_INIT SIG_ATOMIC_MAX extern __thread fast_pthread_once_t _fast_pthread_once_per_thread_epoch; #ifdef __cplusplus extern "C" { #endif extern void fast_pthread_once( pthread_once_t *once, void (*func)(void) ); inline static void fast_pthread_once_inline( fast_pthread_once_t *once, void (*func)(void) ) { fast_pthread_once_t x = *once; /* unprotected access */ if ( x _fast_pthread_once_per_thread_epoch ) { fast_pthread_once( once, func ); } } #ifdef __cplusplus } #endif #endif FAST_PTHREAD_ONCE_H Source fast_pthread_once.c The source is written in C. The lines of the primary function are numbered for reference in the subsequent correctness argument. #include "fast_pthread_once.h" #include static pthread_mutex_t mu = PTHREAD_MUTEX_INITIALIZER; /* protects global_epoch and all fast_pthread_once_t writes */ static pthread_cond_t cv = PTHREAD_COND_INITIALIZER; /* signalled whenever a fast_pthread_once_t is finalized */ #define BEING_INITIALIZED (FAST_PTHREAD_ONCE_INIT - 1) static fast_pthread_once_t global_epoch = 0; /* under mu */ __thread fast_pthread_once_t _fast_pthread_once_per_thread_epoch; static void check( int x ) { if ( x == 0 ) abort(); } void fast_pthread_once( fast_pthread_once_t *once, void (*func)(void) ) { /*01*/ fast_pthread_once_t x = *once; /* unprotected access */ /*02*/ if ( x _fast_pthread_once_per_thread_epoch ) { /*03*/ check( pthread_mutex_lock(µ) == 0 ); /*04*/ if ( *once == FAST_PTHREAD_ONCE_INIT ) { /*05*/ *once = BEING_INITIALIZED; /*06*/ check( pthread_mutex_unlock(µ) == 0 ); /*07*/ (*func)(); /*08*/ check( pthread_mutex_lock(µ) == 0 ); /*09*/ global_epoch++; /*10*/ *once = global_epoch; /*11*/ check( pthread_cond_broadcast(&cv;) == 0 ); /*12*/ } else { /*13*/ while ( *once == BEING_INITIALIZED ) { /*14*/ check( pthread_cond_wait(&cv;, µ) == 0 ); /*15*/ } /*16*/ } /*17*/ _fast_pthread_once_per_thread_epoch = global_epoch; /*18*/ check (pthread_mutex_unlock(µ) == 0); } } This code from BOOST: #ifndef BOOST_THREAD_PTHREAD_ONCE_HPP #define BOOST_THREAD_PTHREAD_ONCE_HPP // once.hpp // // (C) Copyright 2007-8 Anthony Williams // // Distributed under the Boost Software License, Version 1.0. (See // accompanying file LICENSE_1_0.txt or copy at // http://www.boost.org/LICENSE_1_0.txt) #include #include #include #include "pthread_mutex_scoped_lock.hpp" #include #include #include namespace boost { struct once_flag { boost::uintmax_t epoch; }; namespace detail { BOOST_THREAD_DECL boost::uintmax_t& get_once_per_thread_epoch(); BOOST_THREAD_DECL extern boost::uintmax_t once_global_epoch; BOOST_THREAD_DECL extern pthread_mutex_t once_epoch_mutex; BOOST_THREAD_DECL extern pthread_cond_t once_epoch_cv; } #define BOOST_ONCE_INITIAL_FLAG_VALUE 0 #define BOOST_ONCE_INIT {BOOST_ONCE_INITIAL_FLAG_VALUE} // Based on Mike Burrows fast_pthread_once algorithm as described in // http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2007/n2444.html template void call_once(once_flag& flag,Function f) { static boost::uintmax_t const uninitialized_flag=BOOST_ONCE_INITIAL_FLAG_VALUE; static boost::uintmax_t const being_initialized=uninitialized_flag+1; boost::uintmax_t const epoch=flag.epoch; boost::uintmax_t& this_thread_epoch=detail::get_once_per_thread_epoch(); if(epoch #endif I right understand, boost don't use atomic operation, so code from boost not thread-safe?

  Read the article

• Exception thrown while accessing HTML DataTable in backing bean

  - by Denzil

  Hi folks, I am building a simple application in JSF with the CrUD functionality. I am trying to implement edit functionality using the tomahawk component .I am unable to retrieve the selected row in my backing bean. Here's my JSP file snip: <t:dataTable id="data" binding="#{selectOneRowList.dataTable}" styleClass="scrollerTable" headerClass="standardTable_Header" footerClass="standardTable_Header" rowClasses="standardTable_Row1,standardTable_Row2" columnClasses="standardTable_Column,standardTable_ColumnCentered,standardTable_Column" var="car" value="#{selectOneRowList.list}" sortColumn="#{selectOneRowList.sortColumn}" sortAscending="#{selectOneRowList.sortAscending}" preserveDataModel="false" preserveSort="true" preserveRowStates="true" rows="10" > <h:column> <f:facet name="header"> <h:outputText value="Select"/> </f:facet> <t:selectOneRow groupName="selection" id="hugo" value="#{selectOneRowList.selectedRowIndex}" onchange="submit();" immediate="true" valueChangeListener="#{selectOneRowList.processRowSelection}"/> </h:column> <h:column> <f:facet name="header"> </f:facet> <h:outputText value="#{car.id}" /> </h:column> <h:column> <f:facet name="header"> <h:outputText value="Cars" /> </f:facet> <h:outputText value="#{car.type}" /> </h:column> <t:column sortable="true"> <f:facet name="header"> <h:outputText value="Color" /> </f:facet> <h:outputText value="#{car.color}" /> </t:column> </t:dataTable> Here's my backing bean SelectOneRowList.java : public void editCar(ActionEvent event) { System.out.println("Row number ## " + _selectedRowIndex.toString() + " selected!"); System.out.println("Datatable ::"+ dataTable); System.out.println("Row Count ::" + dataTable.getRowCount()); dataItem = (SimpleCar) getDataTable().getRowData(); //selectedCar = (SimpleCar) _list.get(Integer.parseInt(_selectedRowIndex.toString())); selectedCar = (SimpleCar) dataTable.getRowData(); System.out.println(dataTable.getRowData()); } My DTO{Data Transfer Object} which is SimpleCar.java contains the variables ID, type, color and their respective setters/getters. The dataItem variable is of type "SimpleCar". The dataTable is of type HTMLDataTable. I am able to get the the first 3 SOP's but the 4th SOP isn't printed. I receive the following exception on the server : javax.faces.el.EvaluationException: Exception while invoking expression #{selectOneRowList.editCar} org.apache.myfaces.el.MethodBindingImpl.invoke(MethodBindingImpl.java:156) javax.faces.component.UICommand.broadcast(UICommand.java:89) javax.faces.component.UIViewRoot._broadcastForPhase(UIViewRoot.java:97) javax.faces.component.UIViewRoot.processApplication(UIViewRoot.java:171) org.apache.myfaces.lifecycle.InvokeApplicationExecutor.execute(InvokeApplicationExecutor.java:32) org.apache.myfaces.lifecycle.LifecycleImpl.executePhase(LifecycleImpl.java:95) org.apache.myfaces.lifecycle.LifecycleImpl.execute(LifecycleImpl.java:70) javax.faces.webapp.FacesServlet.service(FacesServlet.java:139) org.apache.myfaces.webapp.filter.ExtensionsFilter.doFilter(ExtensionsFilter.java:341) On click of the edit button the editCar method in my backing bean is invoked. I need to get the data of the selected row in my backing bean. Why is the exception occurring ? The above example is taken from the tomawhawk examples WAR distributed on the website. I have gone through many links including the ones on BalusC but none of them have helped. Regards,

  Read the article

• Var null and not an object when using document.getElementById

  - by Dean

  Hi, I'm doing some work in HTML and JQuery. I have a problem of my textarea and submit button not appearing after the radio button is selected. My HTML looks like this: <html> <head><title>Publications Database | Which spotlight for Publications</title> <script type="text/javascript" src="./jquery.js"></script> <script src="./addSpotlight.js" type="text/javascript" charset="utf-8"></script> </head> <body> <div class="wrapper"> <div class="header"> <div class="headerText">Which spotlight for Publications</div> </div> <div class="mainContent"> <p>Please select the publication that you would like to make the spotlight of this month:</p> <form action="addSpotlight" method="POST" id="form" name="form"> <div class="div29" id="div29"><input type="radio" value="29" name="publicationIDs" >A System For Dynamic Server Allocation in Application Server Clusters, IEEE International Symposium on Parallel and Distributed Processsing with Applications, 2008 </div> <div class="div30" id="div30"><input type="radio" value="30" name="publicationIDs" >Analysing BitTorrent's Seeding Strategies, 7th IEEE/IFIP International Conference on Embedded and Ubiquitous Computing (EUC-09), 2009 </div> <div class="div31" id="div31"><input type="radio" value="31" name="publicationIDs" >The Effect of Server Reallocation Time in Dynamic Resource Allocation, UK Performance Engineering Workshop 2009, 2009 </div> <div class="div32" id="div32"><input type="radio" value="32" name="publicationIDs" >idk, hello, 1992 </div> <div class="div33" id="div33"><input type="radio" value="33" name="publicationIDs" >sad, safg, 1992 </div> <div class="abstractWriteup" id="abstractWriteup"><textarea name="abstract"></textarea> <input type="submit" value="Add Spotlight"></div> </form> </div> </div> </body> </html> My javascript looks like this: $(document).ready( function() { $('.abstractWriteup').hide(); addAbstract(); }); function addAbstract() { var abstractWU = document.getElementById('.abstractWriteup'); $("input[name='publicationIDs']").change(function() { var abstractWU = document.getElementById('.abstractWriteup'); var classNameOfSelected = $("input[name='publicationIDs']").val(); var radioSelected = document.getElementById("div"+classNameOfSelected); var parentDiv = radioSelected.parentNode; parentDiv.insertBefore(radioSelected, abstractWU.nextSibling); $('.abstractWriteup').show(); });}; I have developed this by using Node#insertBefore. When I have had it working it has been rearranging the radio buttons. Thanks in Advance Dean

  Read the article

• Termite colony simulator using java

  - by ashii

  hi everyone, i hve to design a simulator that will maintain an environment, which consists of a collection of patches arranged in a rectangular grid of arbitrary size. Each patch contains zero or more wood chips. A patch may be occupied by one or more termites or predators, which are mobile entities that live within the world and behave according to simple rules. A TERMITE can pick up a wood chip from the patch that it is currently on, or drop a wood chip that it is carrying. Termites travel around the grid by moving randomly from their current patch to a neighbouring patch, in one of four possible directions. New termites may hatch from eggs, and this is simulated by the appearance of a new termite at a random patch within the environment. A PREDATOR moves in a similar way to termites, and if a predator moves onto a patch that is occupied by a termite, then the predator eats the termite. At initialization, the termites, predators, and wood chips are distributed randomly in the environment. Simulation then proceeds in a loop, and the new state of the environment is obtained at each iteration. i have designed the arena using jpanel but im not able to randomnly place wood,termite and predator in that arena. can any one help me out?? my code for the arena is as following: 01 import java.awt.*; 02 import javax.swing.*; 03 04 public class Arena extends JPanel 05 { 06 private static final int Rows = 8; 07 private static final int Cols = 8; 08 public void paint(Graphics g) 09 { 10 Dimension d = this.getSize(); 11 // don't draw both sets of squares, when you can draw one 12 // fill in the entire thing with one color 13 g.setColor(Color.WHITE); 14 // make the background 15 g.fillRect(0,0,d.width,d.height); 16 // draw only black 17 g.setColor(Color.BLACK); 18 // pick a square size based on the smallest dimension 19 int sqsize = ((d.width<d.height) ? d.width/Cols : d.height/Rows); 20 // loop for rows 21 for (int row=0; row<Rows; row++) 22 { 23 int y = row*sqsize; // y stays same for entire row, set here 24 int x = (row%2)*sqsize; // x starts at 0 or one square in 25 for (int i=0; i<Cols/2; i++) 26 { 27 // you will only be drawing half the squares per row 28 // draw square 29 g.fillRect(x,y,sqsize,sqsize); 30 // move two square sizes over 31 x += sqsize*2; 32 } 33 } 34 35 } 36 37 38 39 public void update(Graphics g) { paint(g); } 40 41 42 43 public static void main (String[] args) 44 { 45 46 JFrame frame = new JFrame("Arena"); 47 frame.setSize(600,400); 48 frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); 49 frame.setContentPane(new Arena()); 50 frame.setVisible(true); 51 } 52 53 }

  Read the article

• What version-control system is most trivial to set up and use for toy projects?

  - by Norman Ramsey

  I teach the third required intro course in a CS department. One of my homework assignments asks students to speed up code they have written for a previous assignment. Factor-of-ten speedups are routine; factors of 100 or 1000 are not unheard of. (For a factor of 1000 speedup you have to have made rookie mistakes with malloc().) Programs are improved by a sequence is small changes. I ask students to record and describe each change and the resulting improvement. While you're improving a program it is also possible to break it. Wouldn't it be nice to back out? You can see where I'm going with this: my students would benefit enormously from version control. But there are some caveats: Our computing environment is locked down. Anything that depends on a central repository is suspect. Our students are incredibly overloaded. Not just classes but jobs, sports, music, you name it. For them to use a new tool it has to be incredibly easy and have obvious benefits. Our students do most work in pairs. Getting bits back and forth between accounts is problematic. Could this problem also be solved by distributed version control? Complexity is the enemy. I know setting up a CVS repository is too baffling---I myself still have trouble because I only do it once a year. I'm told SVN is even harder. Here are my comments on existing systems: I think central version control (CVS or SVN) is ruled out because our students don't have the administrative privileges needed to make a repository that they can share with one other student. (We are stuck with Unix file permissions.) Also, setup on CVS or SVN is too hard. darcs is way easy to set up, but it's not obvious how you share things. darcs send (to send patches by email) seems promising but it's not clear how to set it up. The introductory documentation for git is not for beginners. Like CVS setup, it's something I myself have trouble with. I'm soliciting suggestions for what source-control to use with beginning students. I suspect we can find resources to put a thin veneer over an existing system and to simplify existing documentation. We probably don't have resources to write new documentation. So, what's really easy to setup, commit, revert, and share changes with a partner but does not have to be easy to merge or to work at scale? A key constraint is that programming pairs have to be able to share work with each other and only each other, and pairs change every week. Our infrastructure is Linux, Solaris, and Windows with a netapp filer. I doubt my IT staff wants to create a Unix group for each pair of students. Is there an easier solution I've overlooked? (Thanks for the accepted answer, which beats the others on account of its excellent reference to Git Magic as well as the helpful comments.)

  Read the article

• mine phrases (up to 3 words) from a given text

  - by DS_web_developer

  I asked before for a simple solution to my problem (using sphinx search service) but I got nowhere... someone has kindly provided me with this code <?php /** * $Project: GeoGraph $ * $Id$ * * GeoGraph geographic photo archive project * This file copyright (C) 2005 Barry Hunter ([email protected]) * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version 2 * of the License, or (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ /** * Provides the methods for updating the worknet tables * * @package Geograph * @author Barry Hunter <[email protected]> * @version $Revision$ */ function addTwoLetterPhrase($phrase) { global $w2; $w2[$phrase] = (isset($w2[$phrase]))?($w2[$phrase]+1):1; } function addThreeLetterPhrase($phrase) { global $w3; $w3[$phrase] = (isset($w3[$phrase]))?($w3[$phrase]+1):1; } function updateWordnet(&$db,$text,$field,$id) { global $w1,$w2,$w3; $alltext = strtolower(preg_replace('/\W+/',' ',str_replace("'",'',$text))); if (strlen($text)< 1) return; $words = preg_split('/ /',$alltext); $w1 = array(); $w2 = array(); $w3 = array(); //build a list of one word phrases foreach ($words as $word) { $w1[$word] = (isset($w1[$word]))?($w1[$word]+1):1; } //build a list of two word phrases $text = $alltext; $text = preg_replace('/(\w+) (\w+)/e','addTwoLetterPhrase("$1 $2")',$text); $text = $alltext; $text = preg_replace('/(\w+)/','',$text,1); $text = preg_replace('/(\w+) (\w+)/e','addTwoLetterPhrase("$1 $2")',$text); //build a list of three word phrases $text = $alltext; $text = preg_replace('/(\w+) (\w+) (\w+)/e','addThreeLetterPhrase("$1 $2 $3")',$text); $text = $alltext; $text = preg_replace('/(\w+)/','',$text,1); $text = preg_replace('/(\w+) (\w+) (\w+)/e','addThreeLetterPhrase("$1 $2 $3")',$text); $text = $alltext; $text = preg_replace('/(\w+) (\w+)/','',$text,1); $text = preg_replace('/(\w+) (\w+) (\w+)/e','addThreeLetterPhrase("$1 $2 $3")',$text); foreach ($w1 as $word=>$count) { $db->Execute("insert into wordnet1 set gid = $id,words = '$word',$field = $count");// ON DUPLICATE KEY UPDATE $field=$field+$count"); } foreach ($w2 as $word=>$count) { $db->Execute("insert into wordnet2 set gid = $id,words = '$word',$field = $count"); } foreach ($w3 as $word=>$count) { $db->Execute("insert into wordnet3 set gid = $id,words = '$word',$field = $count"); } } ?> It works fine and does almost exactly what I need....... except.... it is not utf8 friendly... I mean... it splits whole words into parts (on special chars) where it shouldn't! so my guess is I should use multibyte functions instead of regular preg_replace... I tried to replace preg_replace with mb_ereg_replace but it is not working as it should... at least not for 2 and 3 words phrases any ideas?

  Read the article

• ERROR: Linux route add command failed: external program exited with error status: 4

  - by JohnMerlino

  A remote machine running fedora uses openvpn, and multiple developers were successfully able to connect to it via their client openvpn. However, I am running Ubuntu 12.04 and I am having trouble connecting to the server via vpn. I copied ca.crt, home.key, and home.crt from the server to my local machine to /etc/openvpn folder. My client.conf file looks like this: ############################################## # Sample client-side OpenVPN 2.0 config file # # for connecting to multi-client server. # # # # This configuration can be used by multiple # # clients, however each client should have # # its own cert and key files. # # # # On Windows, you might want to rename this # # file so it has a .ovpn extension # ############################################## # Specify that we are a client and that we # will be pulling certain config file directives # from the server. client # Use the same setting as you are using on # the server. # On most systems, the VPN will not function # unless you partially or fully disable # the firewall for the TUN/TAP interface. ;dev tap dev tun # Windows needs the TAP-Win32 adapter name # from the Network Connections panel # if you have more than one. On XP SP2, # you may need to disable the firewall # for the TAP adapter. ;dev-node MyTap # Are we connecting to a TCP or # UDP server? Use the same setting as # on the server. ;proto tcp proto udp # The hostname/IP and port of the server. # You can have multiple remote entries # to load balance between the servers. remote xx.xxx.xx.130 1194 ;remote my-server-2 1194 # Choose a random host from the remote # list for load-balancing. Otherwise # try hosts in the order specified. ;remote-random # Keep trying indefinitely to resolve the # host name of the OpenVPN server. Very useful # on machines which are not permanently connected # to the internet such as laptops. resolv-retry infinite # Most clients don't need to bind to # a specific local port number. nobind # Downgrade privileges after initialization (non-Windows only) ;user nobody ;group nogroup # Try to preserve some state across restarts. persist-key persist-tun # If you are connecting through an # HTTP proxy to reach the actual OpenVPN # server, put the proxy server/IP and # port number here. See the man page # if your proxy server requires # authentication. ;http-proxy-retry # retry on connection failures ;http-proxy [proxy server] [proxy port #] # Wireless networks often produce a lot # of duplicate packets. Set this flag # to silence duplicate packet warnings. ;mute-replay-warnings # SSL/TLS parms. # See the server config file for more # description. It's best to use # a separate .crt/.key file pair # for each client. A single ca # file can be used for all clients. ca ca.crt cert home.crt key home.key # Verify server certificate by checking # that the certicate has the nsCertType # field set to "server". This is an # important precaution to protect against # a potential attack discussed here: # http://openvpn.net/howto.html#mitm # # To use this feature, you will need to generate # your server certificates with the nsCertType # field set to "server". The build-key-server # script in the easy-rsa folder will do this. ns-cert-type server # If a tls-auth key is used on the server # then every client must also have the key. ;tls-auth ta.key 1 # Select a cryptographic cipher. # If the cipher option is used on the server # then you must also specify it here. ;cipher x # Enable compression on the VPN link. # Don't enable this unless it is also # enabled in the server config file. comp-lzo # Set log file verbosity. verb 3 # Silence repeating messages ;mute 20 But when I start server and look in /var/log/syslog, I notice the following error: May 27 22:13:51 myuser ovpn-client[5626]: /sbin/route add -net 10.27.12.1 netmask 255.255.255.252 gw 10.27.12.37 May 27 22:13:51 myuser ovpn-client[5626]: ERROR: Linux route add command failed: external program exited with error status: 4 May 27 22:13:51 myuser ovpn-client[5626]: /sbin/route add -net 172.27.12.0 netmask 255.255.255.0 gw 10.27.12.37 May 27 22:13:51 myuser ovpn-client[5626]: /sbin/route add -net 10.27.12.1 netmask 255.255.255.255 gw 10.27.12.37 And I am unable to connect to the server via openvpn: $ ssh [email protected] ssh: connect to host xxx.xx.xx.130 port 22: No route to host What may I be doing wrong?

  Read the article

• How To Switch Back to Outlook 2007 After the 2010 Beta Ends

  - by Matthew Guay

  Are you switching back to Outlook 2007 after trying out Office 2010 beta?  Here’s how you can restore your Outlook data and keep everything working fine after the switch. Whenever you install a newer version of Outlook, it will convert your profile and data files to the latest format.  This makes them work the best in the newer version of Outlook, but may cause problems if you decide to revert to an older version.  If you installed Outlook 2010 beta, it automatically imported and converted your profile from Outlook 2007.  When the beta expires, you will either have to reinstall Office 2007 or purchase a copy of Office 2010. If you choose to reinstall Office 2007, you may notice an error message each time you open Outlook. Outlook will still work fine and all of your data will be saved, but this error message can get annoying.  Here’s how you can create a new profile, import all of your old data, and get rid of this error message. Banish the Error Message with a New Profile To get rid of this error message, we need to create a new Outlook profile.  First, make sure your Outlook data files are backed up.  Your messages, contacts, calendar, and more are stored in a .pst file in your appdata folder.  Enter the following in the address bar of an Explorer window to open your Outlook data folder, and replace username with your user name: C:\Users\username\AppData\Local\Microsoft\Outlook Copy the Outlook Personal Folders (.pst) files that contain your data. Its name is usually your email address, though it may have a different name.  If in doubt, select all of the Outlook Personal Folders files, copy them, and save them in another safe place (such as your Documents folder). Now, let’s remove your old profile.  Open Control Panel, and select Mail.  In Windows Vista or 7, simply enter “Mail” in the search box and select the first entry. Click the “Show Profiles…” button. Now, select your Outlook profile, and click Remove.  This will not delete your data files, but will remove them from Outlook. Press Yes to confirm that you wish to remove this profile. Open Outlook, and you will be asked to create a new profile.  Enter a name for your new profile, and press Ok. Now enter your email account information to setup Outlook as normal. Outlook will attempt to automatically configure your account settings.  This usually works for accounts with popular email systems, but if it fails to find your information you can enter it manually.  Press finish when everything’s done. Outlook will now go ahead and download messages from your email account.  In our test, we used a Gmail account that still had all of our old messages online.  Those files are backed up in our old Outlook data files, so we can save time and not download them.  Click the Send/Receive button on the bottom of the window, and select “Cancel Send/Receive”. Restore Your Old Outlook Data Let’s add our old Outlook file back to Outlook 2007.  Exit Outlook, and then go back to Control Panel, and select Mail as above.  This time, click the Data Files button. Click the Add button on the top left. Select “Office Outlook Personal Folders File (.pst)”, and click Ok. Now, select your old Outlook data file.  It should be in the folder that opens by default; if not, browse to the backup copy we saved earlier, and select it. Press Ok at the next dialog to accept the default settings. Now, select the data file we just imported, and click “Set as Default”. Now, all of your old messages, appointments, contacts, and everything else will be right in Outlook ready for you.  Click Ok, and then open Outlook to see the change. All of the data that was in Outlook 2010 is now ready to use in Outlook 2007.  You won’t have to wait to re-download all of your emails from the server since everything’s still here ready to be used.  And when you open Outlook, you won’t see any error messages, either! Conclusion Migrating your Outlook profile back to Outlook 2007 is fairly easy, and with these steps, you can avoid seeing an error message every time you open Outlook.  With all your data in tact, you’re ready to get back to work instead of getting frustrated with Outlook.  Many of us use webmail and keep all of our messages in the cloud, but even on broadband connections it can take a long time to download several gigabytes of emails. Similar Articles Productive Geek Tips Opening Attachments in Outlook 2007 by KeyboardQuickly Create Appointments from Tasks with Outlook 2007’s To-Do BarFix For Outlook 2007 Constantly Asking for Password on VistaPin Microsoft Outlook to the Desktop BackgroundOur Look at the LinkedIn Social Connector for Outlook TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Download Free MP3s from Amazon Awe inspiring, inter-galactic theme (Win 7) Case Study – How to Optimize Popular Wordpress Sites Restore Hidden Updates in Windows 7 & Vista Iceland an Insurance Job? Find Downloads and Add-ins for Outlook

  Read the article

• Our Look at the Internet Explorer 9 Platform Preview

  - by Asian Angel

  Have you been hearing all about Microsoft’s work on Internet Explorer 9 and are curious about it? If you are wanting a taste of the upcoming release then join us as we take a look at the Internet Explorer 9 Platform Preview. Note: Windows Vista and Server 2008 users may need to install a Platform Update (see link at bottom for more information). Getting Started If you are curious about the systems that the platform preview will operate on here is an excerpt from the FAQ page (link provided below). There are two important points of interest here: The platform preview does not replace your regular Internet Explorer installation The platform preview (and the final version of Internet Explorer 9) will not work on Windows XP There really is not a lot to the install process…basically all that you will have to deal with is the “EULA Window” and the “Install Finished Window”. Note: The platform preview will install to a “Program Files Folder” named “Internet Explorer Platform Preview”. Internet Explorer 9 Platform Preview in Action When you start the platform preview up for the first time you will be presented with the Internet Explorer 9 Test Drive homepage. Do not be surprised that there is not a lot to the UI at this time…but you can get a good idea of how Internet Explorer will act. Note: You will not be able to alter the “Homepage” for the platform preview. Of the four menus available there are two that will be of interest to most people…the “Page & Debug Menus”. If you go to navigate to a new webpage you will need to go through the “Page Menu” unless you have installed the Address Bar Mini-Tool (shown below). Want to see what a webpage will look like in an older version of Internet Explorer? Then choose your version in the “Debug Menu”. We did find it humorous that IE6 was excluded from the choices offered. Here is what the URL entry window looks like if you are using the “Page Menu” to navigate between websites. Here is the main page of the site here displayed in “IE9 Mode”…looking good. Here is the main page viewed in “Forced IE5 Document Mode”. There were some minor differences (colors, sidebar, etc.) in how the main page displayed in comparison to “IE9 Mode”. Being able to switch between modes makes for an interesting experience… As you can see there is not much to the “Context Menu” at the moment. Notice the slightly altered icon for the platform preview… “Add” an Address Bar of Sorts If you would like to use a “make-shift” Address Bar with the platform preview you can set up the portable file (IE9browser.exe) for the Internet Explorer 9 Test Platform Addressbar Mini-Tool. Just place it in an appropriate folder, create a shortcut for it, and it will be ready to go. Here is a close look at the left side of the Address Bar Mini-Tool. You can try to access “IE Favorites” but may have sporadic results like those we experienced during our tests. Note: The Address Bar Mini-Tool will not line up perfectly with the platform preview but still makes a nice addition. And a close look at the right side of the Address Bar Mini-Tool. In order to completely shut down the Address Bar Mini-Tool you will need to click on “Close”. Each time that you enter an address into the Address Bar Mini-Tool it will open a new window/instance of the platform preview. Note: During our tests we noticed that clicking on “Home” in the “Page Menu” opened the previously viewed website but once we closed and restarted the platform preview the test drive website was the starting/home page again. Even if the platform preview is not running the Address Bar Mini-Tool can still run as shown here. Note: You will not be able to move the Address Bar Mini-Tool from its’ locked-in position at the top of the screen. Now for some fun. With just the Address Bar Mini-Tool open you can enter an address and cause the platform preview to open. Here is our example from above now open in the platform preview…good to go. Conclusion During our tests we did experience the occasional crash but overall we were pleased with the platform preview’s performance. The platform preview handled rather well and definitely seemed much quicker than Internet Explorer 8 on our test system (a definite bonus!). If you are an early adopter then this could certainly get you in the mood for the upcoming beta releases! Links Download the Internet Explorer 9 Preview Platform Download the Internet Explorer 9 Test Platform Addressbar Mini-Tool Information about Platform Update for Windows Vista & Server 2008 View the Internet Explorer 9 Platform Preview FAQ Similar Articles Productive Geek Tips Mysticgeek Blog: A Look at Internet Explorer 8 Beta 1 on Windows XPMake Ctrl+Tab in Internet Explorer 7 Use Most Recent OrderRemove ISP Text or Corporate Branding from Internet Explorer Title BarWhy Can’t I Turn the Details/Preview Panes On or Off in Windows Vista Explorer?Prevent Firefox or Internet Explorer from Printing the URL on Every Page TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips DVDFab 6 Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 Awesome Lyrics Finder for Winamp & Windows Media Player Download Videos from Hulu Pixels invade Manhattan Convert PDF files to ePub to read on your iPad Hide Your Confidential Files Inside Images Get Wildlife Photography Tips at BBC’s PhotoMasterClasses

  Read the article

• Geek Fun: Virtualized Old School Windows – Windows 95

  - by Matthew Guay

  Last week we enjoyed looking at Windows 3.1 running in VMware Player on Windows 7.  Today, let’s upgrade our 3.1 to 95, and get a look at how most of us remember Windows from the 90’s. In this demo, we’re running the first release of Windows 95 (version 4.00.950) in VMware Player 3.0 running on Windows 7 x64.  For fun, we ran the 95 upgrade on the 3.1 virtual machine we built last week. Windows 95 So let’s get started.  Here’s the first setup screen.  For the record, Windows 95 installed in about 15 minutes or less in VMware in our test. Strangely, Windows 95 offered several installation choices.  They actually let you choose what extra parts of Windows to install if you wished.  Oh, and who wants to run Windows 95 on your “Portable Computer”?  Most smartphones today are more powerful than the “portable computers” of 95. Your productivity may vastly increase if you run Windows 95.  Anyone want to switch? No, I don’t want to restart … I want to use my computer! Welcome to Windows 95!  Hey, did you know you can launch programs from the Start button? Our quick spin around Windows 95 reminded us why Windows got such a bad reputation in the ‘90’s for being unstable.  We didn’t even get our test copy fully booted after installation before we saw our first error screen.  Windows in space … was that the most popular screensaver in Windows 95, or was it just me? Hello Windows 3.1!  The UI was still outdated in some spots.   Ah, yes, Media Player before it got 101 features to compete with iTunes. But, you couldn’t even play CDs in Media Player.  Actually, CD player was one program I used almost daily in Windows 95 back in the day. Want some new programs?  This help file about new programs designed for Windows 95 lists a lot of outdated names in tech.    And, you really may want some programs.  The first edition of Windows 95 didn’t even ship with Internet Explorer.   We’ve still got Minesweeper, though! My Computer had really limited functionality, and by default opened everything in a new window.  Double click on C:, and it opens in a new window.  Ugh. But Explorer is a bit more like more modern versions. Hey, look, Start menu search!  If only it found the files you were looking for… Now I’m feeling old … this shutdown screen brought back so many memories … of shutdowns that wouldn’t shut down! But, you still have to turn off your computer.  I wonder how many old monitors had these words burned into them? So there’s yet another trip down Windows memory lane.  Most of us can remember using Windows 95, so let us know your favorite (or worst) memory of it!  At least we can all be thankful for our modern computers and operating systems today, right?  Similar Articles Productive Geek Tips Geek Fun: Remember the Old-School SkiFree Game?Geek Fun: Virtualized old school Windows 3.11Stupid Geek Tricks: Tile or Cascade Multiple Windows in Windows 7Stupid Geek Tricks: Select Multiple Windows on the TaskbarHow to Delete a System File in Windows 7 or Vista TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

  Read the article

• Geek Fun: Virtualized Old School Windows – Windows 95

  - by Matthew Guay

  Last week we enjoyed looking at Windows 3.1 running in VMware Player on Windows 7.  Today, let’s upgrade our 3.1 to 95, and get a look at how most of us remember Windows from the 90’s. In this demo, we’re running the first release of Windows 95 (version 4.00.950) in VMware Player 3.0 running on Windows 7 x64.  For fun, we ran the 95 upgrade on the 3.1 virtual machine we built last week. Windows 95 So let’s get started.  Here’s the first setup screen.  For the record, Windows 95 installed in about 15 minutes or less in VMware in our test. Strangely, Windows 95 offered several installation choices.  They actually let you choose what extra parts of Windows to install if you wished.  Oh, and who wants to run Windows 95 on your “Portable Computer”?  Most smartphones today are more powerful than the “portable computers” of 95. Your productivity may vastly increase if you run Windows 95.  Anyone want to switch? No, I don’t want to restart … I want to use my computer! Welcome to Windows 95!  Hey, did you know you can launch programs from the Start button? Our quick spin around Windows 95 reminded us why Windows got such a bad reputation in the ‘90’s for being unstable.  We didn’t even get our test copy fully booted after installation before we saw our first error screen.  Windows in space … was that the most popular screensaver in Windows 95, or was it just me? Hello Windows 3.1!  The UI was still outdated in some spots.   Ah, yes, Media Player before it got 101 features to compete with iTunes. But, you couldn’t even play CDs in Media Player.  Actually, CD player was one program I used almost daily in Windows 95 back in the day. Want some new programs?  This help file about new programs designed for Windows 95 lists a lot of outdated names in tech.    And, you really may want some programs.  The first edition of Windows 95 didn’t even ship with Internet Explorer.   We’ve still got Minesweeper, though! My Computer had really limited functionality, and by default opened everything in a new window.  Double click on C:, and it opens in a new window.  Ugh. But Explorer is a bit more like more modern versions. Hey, look, Start menu search!  If only it found the files you were looking for… Now I’m feeling old … this shutdown screen brought back so many memories … of shutdowns that wouldn’t shut down! But, you still have to turn off your computer.  I wonder how many old monitors had these words burned into them? So there’s yet another trip down Windows memory lane.  Most of us can remember using Windows 95, so let us know your favorite (or worst) memory of it!  At least we can all be thankful for our modern computers and operating systems today, right?  Similar Articles Productive Geek Tips Geek Fun: Remember the Old-School SkiFree Game?Geek Fun: Virtualized old school Windows 3.11Stupid Geek Tricks: Tile or Cascade Multiple Windows in Windows 7Stupid Geek Tricks: Select Multiple Windows on the TaskbarHow to Delete a System File in Windows 7 or Vista TouchFreeze Alternative in AutoHotkey The Icy Undertow Desktop Windows Home Server – Backup to LAN The Clear & Clean Desktop Use This Bookmarklet to Easily Get Albums Use AutoHotkey to Assign a Hotkey to a Specific Window Latest Software Reviews Tinyhacker Random Tips Revo Uninstaller Pro Registry Mechanic 9 for Windows PC Tools Internet Security Suite 2010 PCmover Professional Enable Check Box Selection in Windows 7 OnlineOCR – Free OCR Service Betting on the Blind Side, a Vanity Fair article 30 Minimal Logo Designs that Say More with Less LEGO Digital Designer – Free Create a Personal Website Quickly using Flavors.me

  Read the article

< Previous Page | 296 297 298 299 300 301 302 303 304 305 306 307  | Next Page >