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  • Windows 7 just deleted 4 days of work

    - by Mat
    Hey! I'm just a bit about to freak out. I just finished a project and rebooted my computer. It didn't want to boot anymore so I had to use the Windows 7 system repair option. It ran for a minute and then booted up. Now most of my source code from the last 4 days of work is gone! Background: sometimes (most often after installing new software) my notebook won't boot up anymore. It will just show the little Windows 7 flag, but not read from the hard disk anymore. If I hard-abort and reboot then, it asks me whether to start Windows normally (which won't work) or to run "Windows startup repair". If I run it, it does some stuff for about two or three minutes and then I can boot Windows again. Usually after this, .exe files I added to the computer during previous days are gone - but other files so far were not touched. But now, after this happened, a whole bunch of ".as" (ActionScript source files) from my project are gone! Does anyone know where and whether there's a way to recover them?

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  • Which would be more reliable for data archival - SD card or a generic USB thumbdrive?

    - by Visitor
    I've been thinking lately what should I preferably use for data storage and archival. I will say in advance that I do not use flash memory as the only storage media - I also keep my data on the hard drives and optical disks - flash memory is but one of the several backup solutions that duplicate each other. For the flash memory however I do have a choice - to use a generic USB thumbdrive or a SD card. Are there any indications that SD cards may be better and more reliable? From browsing people's review on the web I see that many complaints about USB sticks have to do with them completely failing, losing file system and stop being recognized by the OS. At the same time, most of the complaints for SD cards deal with just write speeds not holding up to the promise - failure reports are but a portions of those for the USB sticks. Are SD cards indeed more reliable? Am I also correct in my assumptions that SD cards use higher grade NAND chips than USB thumbdrives? At least, for class 10 cards, because the specification dictates the minimum performance and the manufacturers have to preselect better chips. While it is common for USB sticks to promise high speeds "up to XX MB/sec" but the reality is they very often deliver speeds 2-3 times less than promised. Do SD cards get better NAND chips and USB thumbdrives receive the discarded chips? Any thoughts would be appreciated.

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  • Mac OS X - Time Machine backup fails verification - What can I do to save the history?

    - by usermac75
    Hi, How do I make Time Machine to make a new complete backup without losing older versions of backed up files? Verbose: I am using the Time Machine backup on my OS X (Snow Leopard) to backup the whole computer to an external drive. I especially like the "history", i.e. the feature that allows you to restore the older version of a file. Problem: I had some data corruption on my external backup drive, I repaired it with the System Tool for doing that, it found some faults. I had the disk tool repair the external drive. After that, the external drive was OK and I could use Time Machine again. I let Time Machine do one more backup. Now I made a verification according to http://superuser.com/questions/47628/verifying-time-machine-backups, namely along sudo diff -qr . $HOME/Desktop 2>&1 | tee $HOME/timemachine-diff.log However: After doing the command above, several differences and missing files were reported, approx. 200 files in sum. Whereas some of the missing files were cache or excluded directories, the differences do bother me, especially as some important documents from me are listed as differing. How can I make sure that the data on the external drive is synced correctly? Is it possible to have Time Machine to do a complete new backup without losing the history? Or to have Time Machine compare all files for differences and re-write all files that are different? Or can I set some flags on the files that do not match to have them copied again? (like the archive-flag in Windows/Dos). I'd rather not touch the files because I would like to keep the date of last change/date of creation) Thank you for your thoughts!

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  • MicroSD card getting corrupted for no good reason

    - by ChaosR
    I recently bought an MicroSD card online. It's a Sandisk 16GB class 2. However, it has a nasty problem. Every time I fill it with my data, the fat tables get corrupted. I've tried reformatting it, blanking it, doesn't seem to solve the problem. I have tried windows and linux (ubuntu), both have the problem. I've used my usb microsd readers, and even tried putting it in my phone and putting data on it from there. All have this problem. Now the really odd thing is, besides the corrupted file tables, no programs can find anything wrong with the hardware. I've tried both chkdisk and "badblocks -w", neither give any type of error. Now I don't know if the actual data gets corrupted, or if its just filesystem tables. What happens is that one or more folders start showing a load of chinese-charred (random UTF8 symbols I suppose) folders and files, and it is impossible to do anything with those. All the other data (outside of the corrupted folders) seems fine. I've tried to test it, and the problem doesn't seem to show up until I fill the disk upto about 3~4GB. After that I can still access the data. But as soon as I eject/safely remove/unmount it, the bad things happen somehow. Next time I plug it in, the folders I most recently wrote to (but sometimes also the folders I wrote the time before last time to) are all gibberish. Does anybody have any clue what might be going on here?

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  • Recover deleted folder form bookmarks bar?

    - by OverTheRainbow
    I googled for this, but didn't find an answer. I removed a folder in Google Chrome's Bookmarks bar. Chrome says nothing when doing this, and I assumed it wouldn't actually delete the data from the Bookmarks manager, just the folder in the Bookmarks bar. Turns out I was wrong, and now I lost hundred's of URLs. I closed and restarted Chrome since then, so data is apparently no longer on disk. Since Google Sync is on by default, it says I have "536 bookmarks", I installed Chrome on another computer, logged on to Google... but the folder is still gone. I can't believe Chrome doesn't prompt the user with an obvious message for something that important. Is there somehow a way to recover a folder removed from the Bookmarks bar? Thank you. Edit: Amazingly, Chrome doesn't 1) provide a way to remove an item from the Bookmarks bar without also deleting it from the Bookmarks list, and 2) doesn't even warn the user of the consequences when doing so! The only way to recover data is: if you haven't closed the browser yet, make a backup of the Bookmarks file, close the browser, replace the now-leaner Bookmarks file with the previous version, and restart Chrome if you have closed it, recover the file from your backup. You did backup that file, right? ;-)

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  • ionice without effect

    - by tim
    System is Ubuntu 10 LTS 64bit (2.6.35.31), I'm running on xen 4.0, no services active, cron stopped, scheduler is cfq for the disk /usr is mounted from: time find /usr -exec stat {} \; > /dev/null 2>&1 & giving real 0m35.760s user 0m0.270s sys 0m3.910s and time ionice -c3 find /usr -exec stat {} \; > /dev/null 2>&1 & giving real 0m36.110s user 0m0.310s sys 0m4.100s which is exactly as expected, now I run both at the same time: time find /usr -exec stat {} \; > /dev/null 2>&1 & time ionice -c3 find /usr -exec stat {} \; > /dev/null 2>&1 & where to my believe the ioniced version should be much slower while the straight version should be as fast as if running alone. but: straight: real 1m10.430s user 0m0.320s sys 0m3.940s ioniced: real 1m10.230s user 0m0.250s sys 0m4.020s which implies that ionice did not work at all. Any hints?

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  • Can I remove the original file while running "sort"?

    - by Spaceman
    I'm sorting a huge file, around 400 gigabytes. I'm running out of the disk space and I must do something quickly. Let's assume the original file is called original_file. So I execute (simplified) it as "sort original_file | gzip -c output_file" I use /home/tmp as a temporary dir. From what I see, there are a lot of intermediate files, like so: tmpA465 tmpB154 ... and so on. The smallest ones have size 12 megabytes. The largest have ~182 megabytes. So, it seems that the "sort" command have already split the original file into small pieces, and have sorted them, and now it is merging them into bigger parts (which will be, eventually, sorted as well). Please correct me if I'm wrong. Can I remove the original file right now without terminating the sort process? I've been waiting for a few days for that and it's important that the "sort" command will not fail and I will get the result file, finally. The OS is Ubuntu server 13.04, x64. Thanks!

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  • Hourly SQL Server 2005 Slowness (Possibly caused by SYSTEM)

    - by Zorlack
    We're trying to diagnose the cause of slowness on our Database server. We're running the latest rev SQL Server 2005 on Windows 2008x64. The behavior that we're seeing is this: We see the SYSTEM process spike one of the CPUs for about 2 minutes, during this time SQL server slows down by a factor of 10. The slowness lasts until SYSTEM is done, then in an hour everything starts again. During these slowdowns disk writes don't spike, paging doesn't spike, the only noticeable precursor we see is that SYSTEM maxes out one of the sixteen (HT)CPUs. Note that this doesn't happen at the top of the hour, it just happens once an hour, and it shifts a bit depending on the length of the incident. At the moment this is causing intermittent slowdowns, but when the server is really busy it can cause Worker Thread starvation. The server is a Dual Quad Dell R710 with 96GB of RAM and RAID10 data/log disks. Has anyone experienced this kind of problem? Does anyone know where we should look? Edit: SQL Server Version is 9.0.4035

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  • Installing Debian 7.6.0 on Lenovo Y50

    - by Girauder
    I was trying to install Debian on my new laptop: a Lenovo Y50 64bit running Windows 8. I got together with a friend and installed Debian in his computer first and had no problems. However I've tried to install Debian several times using the AMD64 KDE and netinst versions and accomplished nothing. First try: installed the KDE version. Grub would let me choose which operating system I wanted, but when I selected Debian it would only load the command line. Second try: Reinstalled but this time with the netinst version. I only got a black screen where I could type but nothing else. Third Try. Tried the netinst again. This time after making the partitions I got a message that said that no EFI partition was found. I ignored the message and this time it wouldn't even load Grub. only a command like interface with grub rescue or something. Not once did I get an error during the installation. What am I doing wrong? I assume the problem is I need to make an EFI partition or something like that. So why is it that during the first installations I didn't ask me for that. And if that is indeed the problem, How can I solve it? Update So the installation failed again... as predicted. Here you can find the Disk Management picture. http://postimg.org/image/433cpfkjz/ Please somebody help me. I keep getting the grub rescue thing. secure boot is disabled and legacy support is set first.

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  • Best SSD tweak for Windows 7

    - by Nick Berardi
    I have seen many articles about tweaking an SSD, but many of them seem outdated, or too broad (read all Windows XP, Vista, and Windows 7 general tweaks). And I know that Windows 7 has been specifically tweaked for SSD by the Windows team, so I don't want to do something that was written for Windows XP in mind and end up circumventing something the Windows team has specifically designed in to Windows 7. So my question is what are the best SSD tweaks for Windows 7 that you have found to get the performance out of your drive? I hope to make a comprehensive list in the answers below so there won't be so much disinformation in the forums about what to do and what not to do. Here are a few that I see posted up on the forums alot: Disabling Superfetch. Yes or No Disabling Page File or limiting it to a really small size such as 500 MB. Disabling Indexing. Yes or No Disabling Defragmenting. Yes or No What are your thoughts do you have any that have worked for you? When providing an answer please do your best to back it up with a reason and possibly some documentation from MSDN, TechNet, or another credible source.

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  • Slow Routing Over LAN (Wired)

    - by reverendj1
    I'm having issues with my router acting very slow (Adtran Netvanta 3458). We have two networks, let's call them A and B. When I run netperf from two servers on network A (no routing) I get speeds along the lines of 900 Mbps. Which makes sense, since we have all 1Gbps switches. When testing A to B (or vice-versa) I get speeds along the lines of 22Mbps. I have also tested connecting my laptop to the switchports on the router, and testing two servers on network A (no routing) and got speeds around 90 Mbps. Which makes sense since the switchports on the router are 100Mbps. Does anyone have any idea why routing would be so slow? We bought the router over a year ago, and we think it has been doing this since then, but we never actually tested it before. (network B isn't really used much, so we didn't notice much) We were implementing a site-to-site VPN and noticed it was ridiculously slow, so we started testing basic routing performance. I have ruled out cabling and router CPU/memory utilization. Adtran looked at my config, but didn't see anything wrong with it.

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  • Computers on network crashing

    - by Phil Cross
    We have recently upgraded our network to Windows 7 clients with Windows server 2008 servers. The upgrade was completed by the end of September and until now has been fine (apart from the minor bugs). Recently (within the last 2 weeks) we've notice all computers on the network (around 1000) start to slow down to the point their unusable. It starts at about 08:45 and finishes at 09:15. Because of this, we think something may be broadcasting across the network. This happens every day, between these times. I cant use my computer at all at the slowdown peak, and looking at task managers performance graphs, Physical memory is hovering around 35% and CPU usage is at 0-10% (idle) yet still crashing. I've looked on DHCPs server log and cant see anything which stands out. The only change we made prior to the slowdown was installing adobe CS6 on some computers, however the slowdown affects computers without CS6. We have 2 physical machines, each with around 5-7 virtual machines running on them with ample memory. Does anyone have any suggestions as to what we can do to narrow down whats causing the crashes? Any help, suggestions or advice would be appreciated.

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  • Corrupted Laptop - Transfer Data Without My Computer (explorer.exe) Using Command Line

    - by nicorellius
    I have a laptop (Toshiba Satellite) that is pretty messed up. The person this belongs too already replaced it with a new machine. My job is to transfer all her data from this machine to disk so that I can transfer it to her. She doesn't want to lose any data (understandably so). Any operation I attempted (i.e., double clicking on any folder icon, like My Documents, My Computer, etc) resulted din a complete crash. The only good news is that I can actually start and navigate around using the command line. Also, I can access the internet. I have a network, so if I can map the drives I can get this thing figured out (hopefully). Also, I tried a USB drive but I couldn't figure out how to access it from the command line. Two questions (I need to use the command line for these): How would I go about accessing the USB drive and how can I map the shared drives on my network so that I may cd to that directory for use of the copy command?

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  • Diagnosing PC crashes (most often while using shared folders or torrents)

    - by Dyppl
    For the last few weeks my PC (pretty old P4 with WinXP SP3) has been crashing randomly. It just suddenly reboots instanteneously. It feels hardware-related but I wasn't able to determine wether it's software or hardware that causes it. I did notice a pattern though: it's more likely to crash when I copy a lot of files over network or have uTorrent running, but sometimes it crashes when I am not doing anything with it. Copying files from it over network causes it to crash in 1 to 10 minutes almost every time. Using torrents causes it to crash every 1-3 hours. With neither or that on it crashes every 24 hours or so. I ruled out the following probable causes: PSU (I bought a new one and turned off most of the drives so the power is sufficient 100%) Bad HDD or interface cable on my SATA disk from which I was originally copying the data over network (bought new SATA cable and later yanked out the HDD completely, PC still crashes without it) Video adapter (AGP slot is now empty, using the onboard VGA at the moment) Network adapter (removed it from PCI, using onboard LAN) CPU (I think: I changed the termopaste and it's temperature is below 50C) RAM (I think: I ran Memtest86 and it didn't show any errors) At the moment I only have only one system HDD and DVD drives, a mouse and a keyboard plugged in. The fact that it crashes most often when I use network extensively makes me think that maybe it's software related (I removed the network adapter from PCI and now am using an onboard one, so network hardware is unlikely to cause problems). I am now pondering system reinstall but it's not a pleasant solution so I decided to ask wether there are better ideas first. If someone can share a good diagnostic tool it would be great because I didn't find anything good. Thanks in advance, I hope that "help to diagnose" questions aren't entirely banned here. EDIT: Motherboard is actually ~4 years old as I replaced it back in 2007

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  • Mac OS X: Applications not responding

    - by Robot55
    This happens to me several times a day. I'll quit an app, the window will close, but the app won't finish shutting down. It stays open in the dock, and right clicking and force quit show not responding. Force quit won't work. I can't shut the app down. Starting any other app when this happens causes that app to behave in exactly the same way: the icon opens in the dock, but the app is non-responsive and can't be forced to quit. Can't access terminal when this happens, because it locks up just like all the apps. While I haven't tried to open every app, I think any app I try to open when this is happening will lock up. If I relaunch Finder, it too locks up and then the only thing left is to hold down the power button for a hard reboot. Any app that is running while this is happening will continue to run normally unless I try to shut it down. Repairing disk permissions has no effect. I also did a time machine and a full restore on a brand new MbP - and sure enough, after restore, the new MbP suffers form the same problem. Creating a new user has no effect. Any thoughts? Please help MacBook Pro 15" AG 2.53ghz i5 cpu 8gb RAM 500gb HD (over 200gb free)

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  • Integrating external computer into a domain - some recommendations please

    - by TomTom
    Given: * A multi loation company. Every office has local routers that connect to a central VPN capable rouer in a data center. All fine so far. We now need to move a computer off site into a hosting center across the globe, to get it closer to some supplier computers we work for. it will run limited logic but latency is important, and our latency so far is too large. This computer will be in a data center and does no require incoming connections except for adminsitrative purposes, although it needs outgoing connetions. I have no real chance to put one of my VPN routers there, sadly - otherwise I would have no problem. Usage of RRAs is not recommended (we had various probblems there over time). I could deal with it. The computer MUSt integrate into the corporate structure via VPN and join the domain and be fully "tracked" (controlled for performance). What is the best suggestion? So far it looks like my best bets woudl be to log in via RRAS and deal with whatever issues arise there plus uise the local firewall the limit incoming connections to this computer to what is needed (which runs down to an emergency RDP connection allowance). Anyone a better idea?

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  • When buying hardware, what sites do you trust for information? [closed]

    - by Matt Dawdy
    I won't ask "what laptop should I buy" since the information is likely to change very quickly. However, I am about to buy a laptop, and I honestly don't know where to begin researching this based on my needs. I am hoping that asking about specific sites that do reviews/recommendations that this will still be on topic. I read the 6 guidelines for subjective questions and believe that this question scores favorably. I'm starting a new job in a few weeks, and they want to know what specific laptop to purchase. I'd like to get the most for their money and get a machine that will not need to be replaced in a year. When looking at a site like Dell, it's hard to get a full picture of the performance of a laptop. Does it work with a docking station, and if so, what kinds of video outs are on it? Will it work well when compiling several large projects in .Net? Has anyone had any issues with the machine getting flaky when dragging it from work to home and back all the time? etc. So, if people would enter in their preferred sites they use when researching hardware, and why they prefer that site (x is great for laptop comparisons, y is great for gaming machine reviews, etc) the I hope that this can be a question with valuable answers to others than just myself.

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  • Windows 7 "freezes" (chills?), and then "unfreezes" for about 1 minute.

    - by gbc001
    Hi, I have an Acer Timeline 1810T netbook (4GB RAM) with Windows 7 x64. About once or twice a day, it "freezes" - the reason i put this in quotation marks is that it does not really freeze, as in you cant move mouse, etc. I can move my mouse and jump between different applications, but I cant use the applications for anything. So I can jump between notepad and Firefox, but I cant browse to a new web page. I have been trying to determine the source of this misery for a while now, and I suspect it has something to do with the hard drive - indirectly if not directly. Here are some screen shots of the resource monitor during a "freeze" and during normal operation: Freeze: http://imgur.com/Gcgq1.jpg Normal operation: imgur.com/mlHaI.jpg As you can see, CPU is fine during freeze, but the disk is going bananas.. Does anyone have an idea of what these reading mean, or about the problem in general? There seems to be no specific activity that sets this off - it can be during browsing, or during media playback with nothing else open. Very appreciative of any help!

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  • Adding SSD as boot drive to existing system

    - by thegrinner
    I recently bought two 128GB SSDs that I'm planning on adding (RAID 0) to a system I currently have on a 1TB HDD. I'm hoping to redo the disk space such that the SSDs act as the boot drive (only other items would be things I install there explicitly) while the majority of my system is on the HDD - documents, media, program files. Something like this: SSD = [ OS | Explicitly placed programs] HDD = [ Program Files | Media | Documents | etc] I have an external drive capable of holding all the data I want to save, so the backup isn't too much of a concern. What I'm worried about is how I should go about doing this - do I need to do a clean install on the SSDs, reformat the HDD, move things like Program Files/Users to the HDD, and then restore data (not full programs but things like saves)? Should I be using one of the regedit hacks I've seen around to change the default install directories instead of moving program files and users? Should I have the actual folders on the HDD and symlinks on the SSD? Or is there a better solution? Do I need to disconnect my HDD while doing the clean Windows install?

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  • How many VPS do I need for my website? [duplicate]

    - by michael
    This question already has an answer here: How do you do load testing and capacity planning for web sites? 3 answers I made a website which aims at simulating a trading market. There are a list of prices and corresponding volumes that people want to purchase. Users can purchase at any price any time. My website retrieves the prices and volumes from my database every 2 seconds (I have to update the user's browser frequently to allow them to see the current market). Users' database INSERT query can be sent any time if they purchase. I used ajax to post or get data from my database (sometimes nested ajax calls). So, every 2 seconds, each user will send or retrieve data by using more than 20 database queries (in order to show a users the current prices and volumes). Also, I may have 200 users at a time. I was not using VPS before, and I got banned because of using too much CPU resources on my host. Now, I've purchased VPS*2 from a hosting servers. I have: CPU Speed: 2000 Mhz Memory: 2048 MB Disk Space: 20000 MB Bandwidth: 2000 GB Connection: 40 Mb/s Dedicated IP's 2 IP's Is this enough for my 200 users? Also, which VPS OS is suitable for me? Thank you.

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  • Perfmon % Processor Time vs. task manager's CPU usage

    - by nat
    I'm new to using Perfmon and performance monitoring in general (so go easy on me please ;) I know that Perfmon doesn't have anything exactly like Task Manager's CPU usage display, but I'm trying to figure out how to monitor user's CPU usage via Perfmon in a similar way, and trying to understand the measurements (or how to convert the numbers to get a similar understanding) For example, if in Task Manager, a particular user is consistently using more than 5% CPU, I would want to contact the user about it. I learn best by example, so here is exactly what I'm trying to do, with a specific example: This is for a 32-bit Dual Quad Core Windows 2003 web server (8 CPUs), there are many web sites on the server, each running within their own application pool/worker process ID. Through other research here I learned of a registry change that I made so that the PID shows up with the w3wp process so I can easily identify the site later by cross-referencing it. I set up a counter with the following settings: Process -> % Processor Time -> all instances Here is an example. Say I'm interested in "black line" user in this graph below, as his process is spiking quite high compared to all the other users: (I wasn't allowed to post the image as I'm a new user on this site.. I've uploaded the image to:) http://i35.tinypic.com/106yn8k.jpg So... using this as an example, I see that they have an AVERAGE % PROCESSOR TIME of 23.264 , and have spiked as high as 103.124 So what exactly does this 23.264 number mean to me? Is it similar to an average of Task Manager's CPU reading for this user? Or, since this server has 8 CPUs, should I divide this number by 8? (23.264/8 = 2.9% AVERAGE CPU LOAD?) Thanks in advance.

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  • Combining MVVM Light Toolkit and Unity 2.0

    - by Alan Cordner
    This is more of a commentary than a question, though feedback would be nice. I have been tasked to create the user interface for a new project we are doing. We want to use WPF and I wanted to learn all of the modern UI design techniques available. Since I am fairly new to WPF I have been researching what is available. I think I have pretty much settled on using MVVM Light Toolkit (mainly because of its "Blendability" and the EventToCommand behavior!), but I wanted to incorporate IoC also. So, here is what I have come up with. I have modified the default ViewModelLocator class in a MVVM Light project to use a UnityContainer to handle dependency injections. Considering I didn't know what 90% of these terms meant 3 months ago, I think I'm on the right track. // Example of MVVM Light Toolkit ViewModelLocator class that implements Microsoft // Unity 2.0 Inversion of Control container to resolve ViewModel dependencies. using Microsoft.Practices.Unity; namespace MVVMLightUnityExample { public class ViewModelLocator { public static UnityContainer Container { get; set; } #region Constructors static ViewModelLocator() { if (Container == null) { Container = new UnityContainer(); // register all dependencies required by view models Container .RegisterType<IDialogService, ModalDialogService>(new ContainerControlledLifetimeManager()) .RegisterType<ILoggerService, LogFileService>(new ContainerControlledLifetimeManager()) ; } } /// <summary> /// Initializes a new instance of the ViewModelLocator class. /// </summary> public ViewModelLocator() { ////if (ViewModelBase.IsInDesignModeStatic) ////{ //// // Create design time view models ////} ////else ////{ //// // Create run time view models ////} CreateMain(); } #endregion #region MainViewModel private static MainViewModel _main; /// <summary> /// Gets the Main property. /// </summary> public static MainViewModel MainStatic { get { if (_main == null) { CreateMain(); } return _main; } } /// <summary> /// Gets the Main property. /// </summary> [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Justification = "This non-static member is needed for data binding purposes.")] public MainViewModel Main { get { return MainStatic; } } /// <summary> /// Provides a deterministic way to delete the Main property. /// </summary> public static void ClearMain() { _main.Cleanup(); _main = null; } /// <summary> /// Provides a deterministic way to create the Main property. /// </summary> public static void CreateMain() { if (_main == null) { // allow Unity to resolve the view model and hold onto reference _main = Container.Resolve<MainViewModel>(); } } #endregion #region OrderViewModel // property to hold the order number (injected into OrderViewModel() constructor when resolved) public static string OrderToView { get; set; } /// <summary> /// Gets the OrderViewModel property. /// </summary> public static OrderViewModel OrderViewModelStatic { get { // allow Unity to resolve the view model // do not keep local reference to the instance resolved because we need a new instance // each time - the corresponding View is a UserControl that can be used multiple times // within a single window/view // pass current value of OrderToView parameter to constructor! return Container.Resolve<OrderViewModel>(new ParameterOverride("orderNumber", OrderToView)); } } /// <summary> /// Gets the OrderViewModel property. /// </summary> [System.Diagnostics.CodeAnalysis.SuppressMessage("Microsoft.Performance", "CA1822:MarkMembersAsStatic", Justification = "This non-static member is needed for data binding purposes.")] public OrderViewModel Order { get { return OrderViewModelStatic; } } #endregion /// <summary> /// Cleans up all the resources. /// </summary> public static void Cleanup() { ClearMain(); Container = null; } } } And the MainViewModel class showing dependency injection usage: using GalaSoft.MvvmLight; using Microsoft.Practices.Unity; namespace MVVMLightUnityExample { public class MainViewModel : ViewModelBase { private IDialogService _dialogs; private ILoggerService _logger; /// <summary> /// Initializes a new instance of the MainViewModel class. This default constructor calls the /// non-default constructor resolving the interfaces used by this view model. /// </summary> public MainViewModel() : this(ViewModelLocator.Container.Resolve<IDialogService>(), ViewModelLocator.Container.Resolve<ILoggerService>()) { if (IsInDesignMode) { // Code runs in Blend --> create design time data. } else { // Code runs "for real" } } /// <summary> /// Initializes a new instance of the MainViewModel class. /// Interfaces are automatically resolved by the IoC container. /// </summary> /// <param name="dialogs">Interface to dialog service</param> /// <param name="logger">Interface to logger service</param> public MainViewModel(IDialogService dialogs, ILoggerService logger) { _dialogs = dialogs; _logger = logger; if (IsInDesignMode) { // Code runs in Blend --> create design time data. _dialogs.ShowMessage("Running in design-time mode!", "Injection Constructor", DialogButton.OK, DialogImage.Information); _logger.WriteLine("Running in design-time mode!"); } else { // Code runs "for real" _dialogs.ShowMessage("Running in run-time mode!", "Injection Constructor", DialogButton.OK, DialogImage.Information); _logger.WriteLine("Running in run-time mode!"); } } public override void Cleanup() { // Clean up if needed _dialogs = null; _logger = null; base.Cleanup(); } } } And the OrderViewModel class: using GalaSoft.MvvmLight; using Microsoft.Practices.Unity; namespace MVVMLightUnityExample { /// <summary> /// This class contains properties that a View can data bind to. /// <para> /// Use the <strong>mvvminpc</strong> snippet to add bindable properties to this ViewModel. /// </para> /// <para> /// You can also use Blend to data bind with the tool's support. /// </para> /// <para> /// See http://www.galasoft.ch/mvvm/getstarted /// </para> /// </summary> public class OrderViewModel : ViewModelBase { private const string testOrderNumber = "123456"; private Order _order; /// <summary> /// Initializes a new instance of the OrderViewModel class. /// </summary> public OrderViewModel() : this(testOrderNumber) { } /// <summary> /// Initializes a new instance of the OrderViewModel class. /// </summary> public OrderViewModel(string orderNumber) { if (IsInDesignMode) { // Code runs in Blend --> create design time data. _order = new Order(orderNumber, "My Company", "Our Address"); } else { _order = GetOrder(orderNumber); } } public override void Cleanup() { // Clean own resources if needed _order = null; base.Cleanup(); } } } And the code that could be used to display an order view for a specific order: public void ShowOrder(string orderNumber) { // pass the order number to show to ViewModelLocator to be injected //into the constructor of the OrderViewModel instance ViewModelLocator.OrderToShow = orderNumber; View.OrderView orderView = new View.OrderView(); } These examples have been stripped down to show only the IoC ideas. It took a lot of trial and error, searching the internet for examples, and finding out that the Unity 2.0 documentation is lacking (at best) to come up with this solution. Let me know if you think it could be improved.

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  • Benchmark Linq2SQL, Subsonic2, Subsonic3 - Any other ideas to make them faster ?

    - by Aristos
    I am working with Subsonic 2 more than 3 years now... After Linq appears and then Subsonic 3, I start thinking about moving to the new Linq futures that are connected to sql. I must say that I start move and port my subsonic 2 with SubSonic 3, and very soon I discover that the speed was so slow thats I didn't believe it - and starts all that tests. Then I test Linq2Sql and see also a delay - compare it with Subsonic 2. My question here is, especial for the linq2sql, and the up-coming dotnet version 4, what else can I do to speed it up ? What else on linq2sql settings, or classes, not on this code that I have used for my messures I place here the project that I make the tests, also the screen shots of the results. How I make the tests - and the accurate of my measures. I use only for my question Google chrome, because its difficult for me to show here a lot of other measures that I have done with more complex programs. This is the most simple one, I just measure the Data Read. How can I prove that. I make a simple Thread.Sleep(10 seconds) and see if I see that 10 seconds on Google Chrome Measure, and yes I see it. here are more test with this Sleep thead to see whats actually Chrome gives. 10 seconds delay 100 ms delay Zero delay There is only a small 15ms thats get on messure, is so small compare it with the rest of my tests that I do not care about. So what I measure I measure just the data read via each method - did not count the data or database delay, or any disk read or anything like that. Later on the image with the result I show that no disk activity exist on the measures See this image to see what really I measure and if this is correct Why I chose this kind of test Its simple, it's real, and it's near my real problem that I found the delay of subsonic 3 in real program with real data. Now lets tests the dals Start by see this image I have 4-5 calls on every method, the one after the other. The results are. For a loop of 100 times, ask for 5 Rows, one not exist, approximatively.. Simple adonet:81ms SubSonic 2 :210ms linq2sql :1.70sec linq2sql using CompiledQuery.Compile :239ms Subsonic 3 :15.00sec (wow - extreme slow) The project http://www.planethost.gr/DalSpeedTests.rar Can any one confirm this benchmark, or make any optimizations to help me out ? Other tests Some one publish here this link http://ormbattle.net/ (and then remove it - don not know why) In this page you can find a really useful advanced tests for all, except subsonic 2 and subsonic 3 that I have here ! Optimizing What I really ask here is if some one can now any trick how to optimize the DALs, not by changing the test code, but by changing the code and the settings on each dal. For example... Optimizing Linq2SQL I start search how to optimize Linq2sql and found this article, and maybe more exist. Finally I make the tricks from that page to run, and optimize the code using them all. The speed was near 1.50sec from 1.70.... big improvement, but still slow. Then I found a different way - same idea article, and wow ! the speed is blow up. Using this trick with CompiledQuery.Compile, the time from 1.5sec is now 239ms. Here is the code for the precompiled... Func<DataClassesDataContext, int, IQueryable<Product>> compiledQuery = CompiledQuery.Compile((DataClassesDataContext meta, int IdToFind) => (from myData in meta.Products where myData.ProductID.Equals(IdToFind) select myData)); StringBuilder Test = new StringBuilder(); int[] MiaSeira = { 5, 6, 10, 100, 7 }; using (DataClassesDataContext context = new DataClassesDataContext()) { context.ObjectTrackingEnabled = false; for (int i = 0; i < 100; i++) { foreach (int EnaID in MiaSeira) { var oFindThat2P = compiledQuery(context, EnaID); foreach (Product One in oFindThat2P) { Test.Append("<br />"); Test.Append(One.ProductName); } } } } Optimizing SubSonic 3 and problems I make many performance profiling, and start change the one after the other and the speed is better but still too slow. I post them on subsonic group but they ignore the problem, they say that everything is fast... Here is some capture of my profiling and delay points inside subsonic source code I have end up that subsonic3 make more call on the structure of the database rather than on data itself. Needs to reconsider the hole way of asking for data, and follow the subsonic2 idea if this is possible. Try to make precompile to subsonic 3 like I did in linq2Sql but fail for the moment... Optimizing SubSonic 2 After I discover that subsonic 3 is extreme slow, I start my checks on subsonic 2 - that I have never done before believing that is fast. (and it is) So its come up with some points that can be faster. For example there are many loops like this ones that actually is slow because of string manipulation and compares inside the loop. I must say to you that this code called million of times ! on a period of few minutes ! of data asking from the program. On small amount of tables and small fields maybe this is not a big think for some people, but on large amount of tables, the delay is even more. So I decide and optimize the subsonic 2 by my self, by replacing the string compares, with number compares! Simple. I do that almost on every point that profiler say that is slow. I change also all small points that can be even a little faster, and disable some not so used thinks. The results, 5% faster on NorthWind database, near 20% faster on my database with 250 tables. That is count with 500ms less in 10 seconds process on northwind, 100ms faster on my database on 500ms process time. I do not have captures to show you for that because I have made them with different code, different time, and track them down on paper. Anyway this is my story and my question on all that, what else do you know to make them even faster... For this measures I have use Subsonic 2.2 optimized by me, Subsonic 3.0.0.3 a little optimized by me, and Dot.Net 3.5

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  • Neo4j Windows Plugin Installation desktop V2.M06

    - by user2904850
    I have downloaded and installed the latest Window V2 Community M06 build of Neo4j on a windows 7 64 bit machine (I have tried the 32bit and 64 bit installs). Installation proceeds without and problems and the system runs normally but there is no /plugins directory (on both versions):- \Program Files (x86)\Neo4j Community\ \Program Files (x86)\Neo4j Community\.install4j \Program Files (x86)\Neo4j Community\bin I am trying to install the Spatial plugin .. so I tried creating the \plugins directory. I extracted the zip file and left the zip file in the directory but the plugins are not found:- C:\Users\WFN44217>curl localhost:7474/db/data/ { "extensions" : { }, "node" : "http://localhost:7474/db/data/node", "reference_node" : "http://localhost:7474/db/data/node/0", "node_index" : "http://localhost:7474/db/data/index/node", "relationship_index" : "http://localhost:7474/db/data/index/relationship", "extensions_info" : "http://localhost:7474/db/data/ext", "relationship_types" : "http://localhost:7474/db/data/relationship/types", "batch" : "http://localhost:7474/db/data/batch", "cypher" : "http://localhost:7474/db/data/cypher", "transaction" : "http://localhost:7474/db/data/transaction", "neo4j_version" : "2.0.0-M06" } I have tried some other plugins, but these are also not found. Any idea what might be missing? Extract from the log files: 2013-10-17 11:19:31.881+0000 INFO [o.n.k.i.DiagnosticsManager]: VM Arguments: [-Dexe4j.semaphoreName=Local\c:_program_files_neo4j_community_bin_neo4j-community.exe, -Dexe4j.isInstall4j=true, -Dexe4j.moduleName=C:\Program Files\Neo4j Community\bin\neo4j-community.exe, -Dexe4j.processCommFile=C:\Users\WFN44217\AppData\Local\Temp\e4j_p6384.tmp, -Dexe4j.tempDir=, -Dexe4j.unextractedPosition=0, -Djava.library.path=C:\Windows\system32;C:\Windows;C:\Windows\System32\Wbem;C:\Windows\System32\WindowsPowerShell\v1.0\;C:\Program Files\Microsoft\Web Platform Installer\;C:\Program Files (x86)\Microsoft ASP.NET\ASP.NET Web Pages\v1.0\;C:\Program Files (x86)\Windows Kits\8.0\Windows Performance Toolkit\;C:\Program Files\Microsoft SQL Server\110\Tools\Binn\;C:\Program Files\Microsoft SQL Server\110\DTS\Binn\;C:\Program Files (x86)\Microsoft SQL Server\110\Tools\Binn\;C:\Program Files (x86)\Microsoft SQL Server\110\Tools\Binn\ManagementStudio\;C:\Program Files (x86)\Microsoft SQL Server\110\DTS\Binn\;C:\apache-maven-3.1.1-bin\apache-maven-3.1.1\bin\;C:\Program Files\Java\jdk1.7.0_40\bin\;C:\Program Files (x86)\Git\cmd;C:\Program Files (x86)\Git\bin;c:\ikvm-7.2.4630.5\bin;C:\Program Files\nodejs\;C:\Users\WFN44217\AppData\Roaming\npm;c:\program files\neo4j community\jre\bin, -Dexe4j.consoleCodepage=cp0, -Dinstall4j.launcherId=24, -Dinstall4j.swt=false] 2013-10-17 11:19:31.881+0000 INFO [o.n.k.i.DiagnosticsManager]: Java classpath: 2013-10-17 11:19:31.883+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.0] file:/C:/Program%20Files/Neo4j%20Community/bin/neo4j-desktop-2.0.0-M06.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\charsets.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [classpath] C:\Program Files\Neo4j Community\.install4j\i4jruntime.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/jaccess.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/zipfs.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\resources.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\jfr.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\jsse.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [classpath] C:\Program Files\Neo4j Community\bin\neo4j-desktop-2.0.0-M06.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/sunec.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\classes 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\rt.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.0] file:/C:/Program%20Files/Neo4j%20Community/bin/ 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/sunmscapi.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/dns_sd.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/dnsns.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/sunjce_provider.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/localedata.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.1] file:/C:/Program%20Files/Neo4j%20Community/jre/lib/ext/access-bridge-64.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [loader.0] file:/C:/Program%20Files/Neo4j%20Community/.install4j/i4jruntime.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\sunrsasign.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: [bootstrap] C:\Program Files\Neo4j Community\jre\lib\jce.jar 2013-10-17 11:19:31.884+0000 INFO [o.n.k.i.DiagnosticsManager]: Library path: 2013-10-17 11:19:31.885+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Windows\System32 2013-10-17 11:19:31.885+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Windows 2013-10-17 11:19:31.885+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Windows\System32\wbem 2013-10-17 11:19:31.885+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Windows\System32\WindowsPowerShell\v1.0 2013-10-17 11:19:31.886+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files\Microsoft\Web Platform Installer 2013-10-17 11:19:31.886+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Microsoft ASP.NET\ASP.NET Web Pages\v1.0 2013-10-17 11:19:31.886+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Windows Kits\8.0\Windows Performance Toolkit 2013-10-17 11:19:31.886+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files\Microsoft SQL Server\110\Tools\Binn 2013-10-17 11:19:31.887+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files\Microsoft SQL Server\110\DTS\Binn 2013-10-17 11:19:31.887+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Microsoft SQL Server\110\Tools\Binn 2013-10-17 11:19:31.887+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Microsoft SQL Server\110\Tools\Binn\ManagementStudio 2013-10-17 11:19:31.888+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Microsoft SQL Server\110\DTS\Binn 2013-10-17 11:19:31.888+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\apache-maven-3.1.1-bin\apache-maven-3.1.1\bin 2013-10-17 11:19:31.888+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files\Java\jdk1.7.0_40\bin 2013-10-17 11:19:31.888+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Git\cmd 2013-10-17 11:19:31.889+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files (x86)\Git\bin 2013-10-17 11:19:31.889+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\ikvm-7.2.4630.5\bin 2013-10-17 11:19:31.889+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files\nodejs 2013-10-17 11:19:31.889+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Users\WFN44217\AppData\Roaming\npm 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: C:\Program Files\Neo4j Community\jre\bin 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: System.properties: 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: exe4j.moduleName = C:\Program Files\Neo4j Community\bin\neo4j-community.exe 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: exe4j.processCommFile = C:\Users\WFN44217\AppData\Local\Temp\e4j_p6384.tmp 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: exe4j.semaphoreName = Local\c:_program_files_neo4j_community_bin_neo4j-community.exe 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: sun.boot.library.path = c:\program files\neo4j community\jre\bin 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: exe4j.consoleCodepage = cp0 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: path.separator = ; 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: file.encoding.pkg = sun.io 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: user.country = GB 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: user.script = 2013-10-17 11:19:31.890+0000 INFO [o.n.k.i.DiagnosticsManager]: sun.os.patch.level = Service Pack 1 2013-10-17 11:19:31.891+0000 INFO [o.n.k.i.DiagnosticsManager]: install4j.exeDir = C:\Program Files\Neo4j Community\bin\ 2013-10-17 11:19:31.891+0000 INFO [o.n.k.i.DiagnosticsManager]: user.dir = C:\Program Files\Neo4j Community\bin

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  • Traditional IO vs memory-mapped

    - by Senne
    I'm trying to illustrate the difference in performance between traditional IO and memory mapped files in java to students. I found an example somewhere on internet but not everything is clear to me, I don't even think all steps are nececery. I read a lot about it here and there but I'm not convinced about a correct implementation of neither of them. The code I try to understand is: public class FileCopy{ public static void main(String args[]){ if (args.length < 1){ System.out.println(" Wrong usage!"); System.out.println(" Correct usage is : java FileCopy <large file with full path>"); System.exit(0); } String inFileName = args[0]; File inFile = new File(inFileName); if (inFile.exists() != true){ System.out.println(inFileName + " does not exist!"); System.exit(0); } try{ new FileCopy().memoryMappedCopy(inFileName, inFileName+".new" ); new FileCopy().customBufferedCopy(inFileName, inFileName+".new1"); }catch(FileNotFoundException fne){ fne.printStackTrace(); }catch(IOException ioe){ ioe.printStackTrace(); }catch (Exception e){ e.printStackTrace(); } } public void memoryMappedCopy(String fromFile, String toFile ) throws Exception{ long timeIn = new Date().getTime(); // read input file RandomAccessFile rafIn = new RandomAccessFile(fromFile, "rw"); FileChannel fcIn = rafIn.getChannel(); ByteBuffer byteBuffIn = fcIn.map(FileChannel.MapMode.READ_WRITE, 0,(int) fcIn.size()); fcIn.read(byteBuffIn); byteBuffIn.flip(); RandomAccessFile rafOut = new RandomAccessFile(toFile, "rw"); FileChannel fcOut = rafOut.getChannel(); ByteBuffer writeMap = fcOut.map(FileChannel.MapMode.READ_WRITE,0,(int) fcIn.size()); writeMap.put(byteBuffIn); long timeOut = new Date().getTime(); System.out.println("Memory mapped copy Time for a file of size :" + (int) fcIn.size() +" is "+(timeOut-timeIn)); fcOut.close(); fcIn.close(); } static final int CHUNK_SIZE = 100000; static final char[] inChars = new char[CHUNK_SIZE]; public static void customBufferedCopy(String fromFile, String toFile) throws IOException{ long timeIn = new Date().getTime(); Reader in = new FileReader(fromFile); Writer out = new FileWriter(toFile); while (true) { synchronized (inChars) { int amountRead = in.read(inChars); if (amountRead == -1) { break; } out.write(inChars, 0, amountRead); } } long timeOut = new Date().getTime(); System.out.println("Custom buffered copy Time for a file of size :" + (int) new File(fromFile).length() +" is "+(timeOut-timeIn)); in.close(); out.close(); } } When exactly is it nececary to use RandomAccessFile? Here it is used to read and write in the memoryMappedCopy, is it actually nececary just to copy a file at all? Or is it a part of memorry mapping? In customBufferedCopy, why is synchronized used here? I also found a different example that -should- test the performance between the 2: public class MappedIO { private static int numOfInts = 4000000; private static int numOfUbuffInts = 200000; private abstract static class Tester { private String name; public Tester(String name) { this.name = name; } public long runTest() { System.out.print(name + ": "); try { long startTime = System.currentTimeMillis(); test(); long endTime = System.currentTimeMillis(); return (endTime - startTime); } catch (IOException e) { throw new RuntimeException(e); } } public abstract void test() throws IOException; } private static Tester[] tests = { new Tester("Stream Write") { public void test() throws IOException { DataOutputStream dos = new DataOutputStream( new BufferedOutputStream( new FileOutputStream(new File("temp.tmp")))); for(int i = 0; i < numOfInts; i++) dos.writeInt(i); dos.close(); } }, new Tester("Mapped Write") { public void test() throws IOException { FileChannel fc = new RandomAccessFile("temp.tmp", "rw") .getChannel(); IntBuffer ib = fc.map( FileChannel.MapMode.READ_WRITE, 0, fc.size()) .asIntBuffer(); for(int i = 0; i < numOfInts; i++) ib.put(i); fc.close(); } }, new Tester("Stream Read") { public void test() throws IOException { DataInputStream dis = new DataInputStream( new BufferedInputStream( new FileInputStream("temp.tmp"))); for(int i = 0; i < numOfInts; i++) dis.readInt(); dis.close(); } }, new Tester("Mapped Read") { public void test() throws IOException { FileChannel fc = new FileInputStream( new File("temp.tmp")).getChannel(); IntBuffer ib = fc.map( FileChannel.MapMode.READ_ONLY, 0, fc.size()) .asIntBuffer(); while(ib.hasRemaining()) ib.get(); fc.close(); } }, new Tester("Stream Read/Write") { public void test() throws IOException { RandomAccessFile raf = new RandomAccessFile( new File("temp.tmp"), "rw"); raf.writeInt(1); for(int i = 0; i < numOfUbuffInts; i++) { raf.seek(raf.length() - 4); raf.writeInt(raf.readInt()); } raf.close(); } }, new Tester("Mapped Read/Write") { public void test() throws IOException { FileChannel fc = new RandomAccessFile( new File("temp.tmp"), "rw").getChannel(); IntBuffer ib = fc.map( FileChannel.MapMode.READ_WRITE, 0, fc.size()) .asIntBuffer(); ib.put(0); for(int i = 1; i < numOfUbuffInts; i++) ib.put(ib.get(i - 1)); fc.close(); } } }; public static void main(String[] args) { for(int i = 0; i < tests.length; i++) System.out.println(tests[i].runTest()); } } I more or less see whats going on, my output looks like this: Stream Write: 653 Mapped Write: 51 Stream Read: 651 Mapped Read: 40 Stream Read/Write: 14481 Mapped Read/Write: 6 What is makeing the Stream Read/Write so unbelievably long? And as a read/write test, to me it looks a bit pointless to read the same integer over and over (if I understand well what's going on in the Stream Read/Write) Wouldn't it be better to read int's from the previously written file and just read and write ints on the same place? Is there a better way to illustrate it? I've been breaking my head about a lot of these things for a while and I just can't get the whole picture..

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