Search Results

Search found 6235 results on 250 pages for 'hdd low'.

Page 101/250 | < Previous Page | 97 98 99 100 101 102 103 104 105 106 107 108  | Next Page >

  • Using different SSDs types (not only SATA based) as system drive

    - by Hubert Kario
    Currently I have a Thinkpad X61s and want to make it both a bit faster and a bit more power efficient. For that reason I thought that adding SSD drive would make most sense. Unfortunately, because of financial reasons, buying SSD of over 200GB capacity is out of reach for me (not only it would be worth more than the rest of the laptop, but also I currently have a 500GB drive in it, so even such a drive would be kind of a downgrade for me). During preliminary testing with a cheap Transcend 4GB Class 6 (14MiB/s streaming, 9MiB/s random read) card I experienced boot times to be reduced by half so putting the OS only on it would already would be an improvement. Unfortunately, my system now is about 11GiB in size so anything less than 16GB would be constraining. In this laptop I can connect additional drives on at least 5 different ways: using SATA-ATA converter caddy in the X6 Ultrabase using internal mini PCIe slot using integrated SDHC slot using CardBus (a.k.a PCMCIA or PC Card) slot using USB Thankfully, because I use only Linux on this PC the bootability of them is irrelevant as I can put the /boot partition on internal HDD and / on any of the above mentioned Flash memories (as I already did for the SDHC test). From what I was able to research and from my own experience those options come with rather big downsides or other problems: SATA-ATA caddy It has three downsides: I have to carry the Ultrabse with me at all times (it's not really inconvenient, but those grams do add) and couldn't disconnect it when I want to disconnect the battery It makes the bay unusable for the optical drive and occasional quick access to other hard drives the only caddies I could buy have rather flaky controllers in them so putting my OS on it would hamper its stability Internal mini PCIe slot This would be an ideal solution, if only I could find real PCIe SSDs, not only devices that could talk only SATA or ATA over PCIe mechanical connection (the ones used in Dell Mini or Asus EEE). Theoretically Samsung did release such devices but I couldn't find them in retail anywhere. Integrated SDHC slot It's a nice solution with a single drawback: the fastest 16GB SDHC card on the market can only do around 35MiB/s read and 15MiB/s write while still costing like a normal 40GB SATA SSD that's 10 times faster. Not really cost-effective. CardBus (a.k.a PCMCIA or PC Card) slot Those cards are much faster than the SDHC option (there are ones that can do well over 50MiB/s read in benchmarks) and from what I could find the PCMCIA controller in my laptop does support UDMA so it should be able to deliver comparable speeds. They still cost similarly to SD cards but at least they provide streaming performance comparable to my current HDD. USB That's the worst option. Not only is it limited to 20-30MiB/s by the interface itself the drive would stick out of the laptop so it's a big no no. The question As such I think that going the "CF in a CardBus adapter" route will be the best option. My question is: did anyone try using CF cards in CardBus adapters as system drives with Linux on Thinkpad laptops? Laptops in general? What was the real-world performance? I don't have any CF cards so I can't check how well does it work with suspend/resume, or whatever it's easy to make it work in initramfs (I'm using ArchLinux and SD card was trivial — add 3 modules in single config line and rebuilding initramfs) so any tips/gotchas on this are welcome as well.

    Read the article

  • Problems with XP, Office, and PC in general - any ideas?

    - by molecule
    Hi all This may not make a whole lot of sense so pls bear with me... I am about to perform a routine check on one of my user's PC. Some background - the PC has a Xeon processor and 4Gb of RAM and running XP SP3 He has 2xHDD and pagefile is hosted on the secondary HDD (D:) and min/max values are set to 4096. NO pagefile on C: This user has 6 monitors so he has an NVIDIA Quadro NVS440 hosting 4xmonitors and an NVIDIA Quadro NVS290 hosting 2xmonitors. There is a video card driver from NVIDIA which is compatible with both NVS440 and NVS290 and he is on the latest version of that driver. (Note: Make of video cards are different - one is from leadtek and the other from Nvidia) He is a heavy Bloomberg, Outlook, Word, and Excel user and runs two Citrix applications. Other apps are FoxIt PDF and IE. Problems - Outlook and Excel frequently crashes - I am going to perform an Outlook and Excel repair and also check/remove unnecessary addins - will he lose any customizations if I repaired and chose "Restore my shortcuts while repairing" and do not select "Discard my customized settings and restore default settings". Does repair really repair anything? FYI - It stopped crashing ever since i moved a large spreadsheet he has open to his local HDD instead of over the network. This spreadsheet "refreshes" constantly as it is pulling live data to update cells and I suspect it was auto-saving so frequently that it caused crashes if saving over the network. At times, his right click completely fails to respond. His left click works fine but he can't right click on anything in any Window and even on the desktop. Sometimes, he needs to start to close certain applications such as Adobe and the right click will start functioning again. I removed Adobe and installed FoxIt as I figured it was a resource issue but I do not think so as he does have sufficient resources when the problem is happening. Sometimes he can't bring task manager up until he kills certain apps. Definitely sounds like a resource issue but I am not confident that is the root cause. Also not sure if this is related to one of the apps installed but his Start bar flickers (does not completely disappear) intermittently from time to time. The taskbar icons which are hidden appear and then get hidden again as if it was having "fits". I have performed reg scans, malware scans etc but problems do not go away. I am planning to perform sfc /scannow and office repair but would like to know if anyone has any other suggestions. What about setting a "small" pagefile on C:. I have heard that this is recommended and may be the reason why a minidmp file was not generated when he encountered a blue screen. Also, any feedback on his video cards? Do you think different models would cause problems? The drivers seem to work but he only has 2.5Gb out of 4Gb available RAM as I believe the video card chomped up a portion of this. I have recommended creating a new profile for him but due to the amount of customisations he has and the amount of time and effort it will take to get him up and running again, he prefers to bear with the problem than to go down that path. However, at least once a week, his PC acts up and I can't think of any other tools or techniques to rectify his problems. I guess we are at a stage where we just want to "stabilize" things so he won't encounter issues that frequently. Any feedback is very much appreciated.

    Read the article

  • Why does my computer run slowly and freeze sometimes?

    - by Brae
    EDIT I disabled sound in the BIOS, rebooted and it hung. I removed the (previously) faulty HDD, rebooted and it hung. I have managed to get my Realtek audio manager open again after its mysterious disappearance. Subsequently my microphone is now working again, to fix it I had to uninstall audio drivers, disable audio in BIOS, install audio drivers, enable audio in BIOS. Access via network (with faulty HDD in) seems to not be triggering hangs at the moment. I think with the sound problem fixed it might play a little nicer, but I think its still going to hang. If it does, then I'm fairly sure its been narrowed down to the mobo. EDIT Pretty convinced my motherboard is the culprit, because nothing else seems to have any obvious problems (bar the hard drive, which the PC still hangs without it being plugged in) So thank you all for helping, once I get more rep ill up a few of the answers. My PC is doing some weird things... Sometimes when I open up a program, lets say Adobe Photoshop, it will load everything normally, nice and quick no problems and I can use it fine. Other times its a little odd, and it loads the program as if it's only using half of the CPU. It's pretty obvious when it does it, normally the loading screen skims past, but when it does this weird load you see it slowly tick though each thing, and the program itself becomes incredibly slow. Even Google Chrome does it sometimes. Yet when I exit and reopen the program without doing anything else, it typically opens fine without lagging. I think this problem is probably a symptom of something bigger, because of other problems I'm having. Random hangs; no matter what I have open or what I'm doing. My PC will sort of freeze up for a few seconds. If music is playing it will either loop the last second or two, or it will buzz. This only lasts for a few seconds then it returns to normal without having to restart. During this time all programs lock up and freeze, and the mouse and keyboard are useless. I am also having a weird issue with my audio jacks, without touching my PC at all, sometimes I will see a popup saying that I have unplugged something or plugged something in, neither of which has actually happened. Pretty sure this is cause by the motherboard. I recently had a 'Pink Screen of Death' (yes pink) which pointed to my audio drivers. The lockups seem to happen with some consistency when someone is accessing my shared files via my home LAN. Which leads me to believe either one of my hard drives is acting up or more likely the controller. One of my drives had a bit of a crash before, I used Spinrite and managed to recover my stuff and now the drive appears to be working okay. This is possibly adding to the problems. My best guess is something has gone wrong with my motherboard, possibly a power issue or a chip has died, I really don't know. So what I would like to know is: Have I have missed some obvious diagnostic to help figure out what it is, or should I just bite the bullet and assume its my motherboard acting up and buy a new system? dxdiag[64-bit] - http://pastebin.com/G30kb2TL PSOD (minidump) - http://pastebin.com/aZsv0H56 HWiNFO64 (system info / specs) - http://pastebin.com/X6h3K8g6

    Read the article

  • .AVI Files randomly cease to open, other strange errors too

    - by Ben Franchuk
    I Recently (a couple weeks ago) downloaded the complete series of Seinfeld, all in varying file type. I Watched them in sequence according to season and to airing date, and all was well. All of the files played fine with my media player of choice ("BS Player"), and once I had finished, I went onto watch some other TV I had previously downloaded (The U.S. Series of "The Office"), and after then, some other film and then some music, over the following weeks (keep in mind all of these files are all on the same Hard Drive). Later then, More recently, I Went back to watching Seinfeld. The episodes played well as they did before- with the exclusion of a few in Season 7. I Have not tested all of the episodes in the season, but upon inspection, the majority of them are experiencing this problem; the problem being simply that they don't open! BS Player says that the files are either damaged or that the codecs to play the files are not on my computer-- however I am certain that the files DO have the codecs, and I am pretty sure that they are NOT DAMAGED either. I Have played the files with other players (such as VLC, Media Player Classic, and Windows Media Player), too, only to the same result; of them not opening. Seemingly the only way that I can differentiate between a damaged file and a non-damaged file are the way that the icon shows in Windows Explorer. For example, the below image is how explorer shows the information of a file that is non-damaged... ...and below is how a damaged file appears... The most disturbing and confusing part of this, though, is the last episode in the season- It opens, but not as a video- Instead, as a 1 Hour, 16 Minute, and 35 Second Audio file! The file plays a song for the first 4 or so minutes, and then is pretty much silent (except for some extremely quiet noise) until the last minute or so, when a random array of chopped up sounds and beeping noises play. I Do not recognise the song at the beginning of the file, but by the sounds of it, it is a song by the artist "Mr. Oizo," who's complete works I downloaded a couple weeks before now; and a bit before then I had finished downloading season 9 (not affected by these problems) of Seinfeld. I'd also like to note that the file I told of earlier (which played audio instead of video) reads as the same size as the other files in the season (around 175 MB) and also opens as a video clip. I Have NEVER experienced any of these problems in the past, and they seem to be only effecting the one season of my downloaded TV. The problems have not arisen with any of the other files on my Hard Drive, or any of the files downloaded around the time or after the time of which I downloaded season 7 of Seinfeld- or at least to my noticing. I Use the hard drive these files are located on almost every day, so could that be the cause of these problems? Is this a sign that my HDD is soon going to die? If it helps, the HDD is a Western Digital MyBook 1.5 TB 7500 RPM. It is connected to the computer via U.S.B. 2.0. EDIT! I noticed that this problem is now occurring with Season 9 of Seinfeld- and, presumably, other files on the drive I have yet to check. Please, If you have ANY IDEA AT ALL on what may be causing this or how to fix it, do tell me!

    Read the article

  • Windows 8.1 Update 1 Disk Usage 100%

    - by Gookjin Jeong
    Background Information / Computer Specs I have a 14-inch Samsung Series 5 Ultra. Core i5 CPU, 750GB HDD, 8GB RAM, Intel HD Graphics 4000. I've had the computer for about 1.5 years with no major problems. Problem The issue appeared at the beginning of April this year, when I updated the OS to Windows 8.1 Update 1 (not from 8 to 8.1). After being on continually (except for at night, when I put it on sleep mode) for about 48 hours, the disk usage as seen by Task Manager hits 100%. When this happens, everything from opening/closing applications to typing and even bringing up the start screen by pressing the Windows key becomes extremely slow. The only way to make the disk usage decrease is to restart the computer. Then the problem repeats. I've used my current laptop (as well as my previous laptops) this way -- putting it on sleep mode at night and restarting it only when Windows needs to install updates -- for a long time. So I know the 100% disk usage is not due to the way I use the computer. The thing that causes the spike varies. Sometimes it's System, sometimes it's one of the various applications I installed (e.g. Chrome, Evernote, Spotify, Wunderlist, iTunes, etc.), and sometimes it's Antimalware Service Executable, etc. Tried Solutions I think I tried almost every solution out there for this problem: Running the check disk command (chkdsk /b /f /v /scan c:) from Admin Command Prompt Running Windows Memory Diagnostic Disabling Superfetch and Windows Search from services.msc Running "Fix problems with Windows Update" from Control Panel -- Troubleshooting Updating and rolling back the graphics driver (Intel HD 4000) Disabling "Use hardware acceleration when available" from Chrome settings Disabling Intel Rapid Storage Technology Running the SFC /SCANNOW command as recommended here Running a quick scan & a full scan from Windows Defender (no threats found) Taking the hard drive out and putting it back Refreshing the computer, from the Update and recovery -- Recovery option in Windows settings NONE of the above worked for me. I was about to give up but then noticed that one of the main culprits of the disk usage spike, as shown in the "Disk Activity" section of the Resource Monitor, was C:\System (pagefile.sys). I googled around and found that one of the recommended solutions was to disable pagefile. I then went to **Control Panel -- System and Security -- System -- Advanced system settings -- Advanced tab -- Performance settings -- Advanced tab -- "Change" under Virtual memory and discovered that the number for "Currently allocated" at the bottom was 1280MB, although the number for "Recommended" was 4533MB. I immediately changed it to 4533MB and checked my family members' computers to see what the numbers were like. All of theirs had a currently allocated space that was only slightly smaller than the recommended space. See screenshot below: This might fix the problem. I'll have to wait a couple more days.But if it doesn't, what in the world should I do next? I'm guessing the hard drive isn't failing because This computer is less than 2 years old; and Speccy says that the status of the HDD is good. Update 5/27/2014 The "4533MB" solution did not work. I had to reboot the computer about 30 minutes ago because the disk usage again hit 100%. When I opened Resource Monitor the C:\System (pagefile.sys) again was shown to be the culprit. I have now disabled pagefile entirely via the same window shown above in the screenshot. The number for "currently allocated" is now 0MB. Will update again in a couple days, or if the problem occurs again, whichever comes sooner.

    Read the article

  • How to fix "BASIC runtime error 1; Type: com.sun.star.uno.Runtime Exception, Message: Toolbar do not exist " error in Libreoffice calc, Ubuntu 12.04

    - by PDeb
    I get the following error while openning a .xls file in Libreoffice Calc, Ubuntu 12.04 [LibreOffice 3.5.5.2; Build ID: 350m 1 (Build:2)] To overcome this I checked the LibreOffice Security Level to Low under Macro Security (from Tools---- Options--- Security tab. Then I went ahead intalling java by running the following commands from the terminal window (with some tips from various forums) sudo add-apt-repository ppa:libreoffice/ppa sudo apt-get update sudo apt-get install libreoffice libreoffice-java-common libreoffice-math libreoffice-gnome libreoffice-java-common Still I got the BASIC runtime error (as in the title), even after clicking Tools---- Options ---- Java and checking the 'Use a Java runtime environment option' and then clicking on 'Sun Microsystems Inc' under listed JRE environments installed. Even I ran the following commands to install latest Java run time environments from terminal window sudo apt-get install openjdk-7-jre icedtea-7-plugin But still I get the same Basicruntime error (details as in the title bar). This particular file opens perfectly in Microsoft Excel 2007, in Win XP Professional.

    Read the article

  • Create a Bootable Ubuntu 9.10 USB Flash Drive

    - by Trevor Bekolay
    The Ubuntu Live CD isn’t just useful for trying out Ubuntu before you install it, you can also use it to maintain and repair your Windows PC. Even if you have no intention of installing Linux, every Windows user should have a bootable Ubuntu USB drive on hand in case something goes wrong in Windows. Creating a bootable USB flash drive is surprisingly easy with a small self-contained application called UNetbootin. It will even download Ubuntu for you! Note: Ubuntu will take up approximately 700 MB on your flash drive, so choose a flash drive with at least 1 GB of free space, formatted as FAT32. This process should not remove any existing files on the flash drive, but to be safe you should backup the files on your flash drive. Put Ubuntu on your flash drive UNetbootin doesn’t require installation; just download the application and run it. Select Ubuntu from the Distribution drop-down box, then 9.10_Live from the Version drop-down box. If you have a 64-bit machine, then select 9.10_Live_x64 for the Version. At the bottom of the screen, select the drive letter that corresponds to the USB drive that you want to put Ubuntu on. If you select USB Drive in the Type drop-down box, the only drive letters available will be USB flash drives. Click OK and UNetbootin will start doing its thing. First it will download the Ubuntu Live CD. Then, it will copy the files from the Ubuntu Live CD to your flash drive. The amount of time it takes will vary depending on your Internet speed, an when it’s done, click on Exit. You’re not planning on installing Ubuntu right now, so there’s no need to reboot. If you look at the USB drive now, you should see a bunch of new files and folders. If you had files on the drive before, they should still be present. You’re now ready to boot your computer into Ubuntu 9.10! How to boot into Ubuntu When the time comes that you have to boot into Ubuntu, or if you just want to test and make sure that your flash drive works properly, you will have to set your computer to boot off of the flash drive. The steps to do this will vary depending on your BIOS – which varies depending on your motherboard. To get detailed instructions on changing how your computer boots, search for your motherboard’s manual (or your laptop’s manual for a laptop). For general instructions, which will suffice for 99% of you, read on. Find the important keyboard keys When your computer boots up, a bunch of words and numbers flash across the screen, usually to be ignored. This time, you need to scan the boot-up screen for a few key words with some associated keys: Boot menu and Setup. Typically, these will show up at the bottom of the screen. If your BIOS has a Boot Menu, then read on. Otherwise, skip to the Hard: Using Setup section. Easy: Using the Boot Menu If your BIOS offers a Boot Menu, then during the boot-up process, press the button associated with the Boot Menu. In our case, this is ESC. Our example Boot Menu doesn’t have the ability to boot from USB, but your Boot Menu should have some options, such as USB-CDROM, USB-HDD, USB-FLOPPY, and others. Try the options that start with USB until you find one that works. Don’t worry if it doesn’t work – you can just restart and try again. Using the Boot Menu does not change the normal boot order on your system, so the next time you start up your computer it will boot from the hard drive as normal. Hard: Using Setup If your BIOS doesn’t offer a Boot Menu, then you will have to change the boot order in Setup. Note: There are some options in BIOS Setup that can affect the stability of your machine. Take care to only change the boot order options. Press the button associated with Setup. In our case, this is F2. If your BIOS Setup has a Boot tab, then switch to it and change the order such that one of the USB options occurs first. There may be several USB options, such as USB-CDROM, USB-HDD, USB-FLOPPY, and others; try them out to see which one works for you. If your BIOS does not have a boot tab, boot order is commonly found in Advanced CMOS Options. Note that this changes the boot order permanently until you change it back. If you plan on only plugging in a bootable flash drive when you want to boot from it, then you could leave the boot order as it is, but you may find it easier to switch the order back to the previous order when you reboot from Ubuntu. Booting into Ubuntu If you set the right boot option, then you should be greeted with the UNetbootin screen. Press enter to start Ubuntu with the default options, or wait 10 seconds for this to happen automatically. Ubuntu will start loading. It should go straight to the desktop with no need for a username or password. And that’s it! From this live desktop session, you can try out Ubuntu, and even install software that is not included in the live CD. Installed software will only last for the duration of your session – the next time you start up the live CD it will be back to its original state. Download UNetbootin from sourceforge.net Similar Articles Productive Geek Tips Create a Bootable Ubuntu USB Flash Drive the Easy WayReset Your Ubuntu Password Easily from the Live CDHow-To Geek on Lifehacker: Control Your Computer with Shortcuts & Speed Up Vista SetupHow To Setup a USB Flash Drive to Install Windows 7Speed up Your Windows Vista Computer with ReadyBoost 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 New Stinger from McAfee Helps Remove ‘FakeAlert’ Threats Google Apps Marketplace: Tools & Services For Google Apps Users Get News Quick and Precise With Newser Scan for Viruses in Ubuntu using ClamAV Replace Your Windows Task Manager With System Explorer Create Talking Photos using Fotobabble

    Read the article

  • Status of stack based languages

    - by Andrea
    I have recently become curious about Factor, which, as far as I understand, is the most practical stack based language around. Forth seems not to be used much these days - I think it is because it was meant to be used on its own, instead of inside an operating system, although ports of course exist. It is also pretty low level. Joy is essentially dead, as the author stated that it does not make sense to mantain it in spite of adopting Factor. The fact is that Factor itself does not seem much developed today. The GitHub repo does not seem very active, and a lot of stuff languishes in unmantained. So, are there any other languages of this type that are more actively mantained? Are any in production use?

    Read the article

  • Hekaton – SQL Server’s in-memory database engine

    - by Christian
    Microsoft have just gone public at the PASS Summit in Seattle about a new SQL Server engine that they’re working on which is optimized for high-memory servers – an in-memory OLTP database engine which is built-in to SQL Server rather than a separate entity.  This means that you can move just the performance critical parts of your database to Hekaton. The new engine really pushes the performance boundaries by eliminating as many instructions as possible: Main memory optimized tables which are decoupled from on-disk structures; Everything is lock and latch free; More work is pushed to compile time so your T-SQL code is compiled natively into low-level code. We’re already working with a customer on an early adoption program so expect to hear from us on what we learn about implementing it!   Christian Bolton - MCA, MCM, MVP Technical Director http://coeo.com - SQL Server Consulting & Managed Services

    Read the article

  • HSDPA modem only working on certain USB ports

    - by nabulke
    Depending on which USB port I use to connect my HSDPA modem, the network manager will connect to the internet or not. I used to work (i.e. established a internet connection automatically) on all ports, but over time it simply stopped on some ports. lsusb output in all cases looks like that (Device ID varies depending on USB port): Bus 001 Device 009: ID 12d1:1003 Huawei Technologies Co., Ltd. E220 HSDPA Modem / E270 HSDPA/HSUPA Modem Any ideas what could cause this behaviour? What can I do to fix this? ADDED One additional information about the modem: if connected via USB it will be available as as harddrive AND as a HSDPA modem (kind of a duality...). In the error case, it will only be shown as a harddrive. ADDITIONAL INFO AS REQUESTED MODEM NOT WORKING Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 002: ID 413c:8000 Dell Computer Corp. BC02 Bluetooth Adapter Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 007: ID 12d1:1003 Huawei Technologies Co., Ltd. E220 HSDPA Modem / E270 HSDPA/HSUPA Modem Bus 001 Device 005: ID 046d:c00c Logitech, Inc. Optical Wheel Mouse Bus 001 Device 004: ID 05e3:0608 Genesys Logic, Inc. USB-2.0 4-Port HUB Bus 001 Device 003: ID 413c:0058 Dell Computer Corp. Port Replicator Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub laptop:~$ dmesg | grep 'usb' [ 0.225371] usbcore: registered new interface driver usbfs [ 0.225387] usbcore: registered new interface driver hub [ 0.225418] usbcore: registered new device driver usb [ 0.504291] usb usb1: configuration #1 chosen from 1 choice [ 0.504767] usb usb2: configuration #1 chosen from 1 choice [ 0.505046] usb usb3: configuration #1 chosen from 1 choice [ 0.505601] usb usb4: configuration #1 chosen from 1 choice [ 1.061064] usb 1-6: new high speed USB device using ehci_hcd and address 3 [ 1.192636] usb 1-6: configuration #1 chosen from 1 choice [ 1.447006] usb 2-2: new full speed USB device using uhci_hcd and address 2 [ 1.634908] usb 2-2: configuration #1 chosen from 1 choice [ 1.708164] usb 1-6.1: new high speed USB device using ehci_hcd and address 4 [ 1.801668] usb 1-6.1: configuration #1 chosen from 1 choice [ 2.076279] usb 1-6.1.1: new low speed USB device using ehci_hcd and address 5 [ 2.174932] usb 1-6.1.1: configuration #1 chosen from 1 choice [ 6.580315] usb 1-6.1.2: new high speed USB device using ehci_hcd and address6 [ 6.683479] usb 1-6.1.2: configuration #1 chosen from 1 choice [ 20.018671] usbcore: registered new interface driver btusb [ 20.131703] usbcore: registered new interface driver usb-storage [ 20.131988] usb-storage: device found at 6 [ 20.131991] usb-storage: waiting for device to settle before scanning [ 20.207981] usb 1-6.1.2: USB disconnect, address 6 [ 20.291499] usbcore: registered new interface driver hiddev [ 20.297052] input: Logitech USB Mouse as /devices/pci0000:00/0000:00:1d.7/usb1/1-6/1-6.1/1-6.1.1/1-6.1.1:1.0/input/input6 [ 20.297465] generic-usb 0003:046D:C00C.0001: input,hidraw0: USB HID v1.10 Mouse [Logitech USB Mouse] on usb-0000:00:1d.7-6.1.1/input0 [ 20.297534] usbcore: registered new interface driver usbhid [ 20.297803] usbhid: v2.6:USB HID core driver [ 26.552360] usb 1-6.1.2: new high speed USB device using ehci_hcd and address 7 [ 26.663506] usb 1-6.1.2: configuration #1 chosen from 1 choice [ 26.709628] usb-storage: device found at 7 [ 26.709631] usb-storage: waiting for device to settle before scanning [ 26.732387] usb-storage: device found at 7 [ 26.732390] usb-storage: waiting for device to settle before scanning [ 31.709568] usb-storage: device scan complete [ 31.733676] usb-storage: device scan complete MODEM WORKING Bus 004 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 003 Device 002: ID 046d:c00c Logitech, Inc. Optical Wheel Mouse Bus 003 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 002 Device 002: ID 413c:8000 Dell Computer Corp. BC02 Bluetooth Adapter Bus 002 Device 001: ID 1d6b:0001 Linux Foundation 1.1 root hub Bus 001 Device 004: ID 12d1:1003 Huawei Technologies Co., Ltd. E220 HSDPA Modem / E270 HSDPA/HSUPA Modem Bus 001 Device 001: ID 1d6b:0002 Linux Foundation 2.0 root hub dmesg | grep 'usb' [ 0.134811] usbcore: registered new interface driver usbfs [ 0.134826] usbcore: registered new interface driver hub [ 0.134858] usbcore: registered new device driver usb [ 0.360327] usb usb1: configuration #1 chosen from 1 choice [ 0.360783] usb usb2: configuration #1 chosen from 1 choice [ 0.361061] usb usb3: configuration #1 chosen from 1 choice [ 0.361611] usb usb4: configuration #1 chosen from 1 choice [ 1.144122] usb 2-2: new full speed USB device using uhci_hcd and address 2 [ 1.346896] usb 2-2: configuration #1 chosen from 1 choice [ 1.588072] usb 3-1: new low speed USB device using uhci_hcd and address 2 [ 1.761204] usb 3-1: configuration #1 chosen from 1 choice [ 5.972042] usb 1-1: new high speed USB device using ehci_hcd and address 4 [ 6.115438] usb 1-1: configuration #1 chosen from 1 choice [ 19.990565] usbcore: registered new interface driver usbserial [ 19.991429] usb-storage: device found at 4 [ 19.991432] usb-storage: waiting for device to settle before scanning [ 20.017260] usbcore: registered new interface driver usb-storage [ 20.017305] usbcore: registered new interface driver usbserial_generic [ 20.017308] usbserial: USB Serial Driver core [ 20.017817] usb-storage: device found at 4 [ 20.017820] usb-storage: waiting for device to settle before scanning [ 20.070796] usbcore: registered new interface driver btusb [ 20.229525] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB0 [ 20.229776] usb 1-1: GSM modem (1-port) converter now attached to ttyUSB1 [ 20.229843] usbcore: registered new interface driver option [ 20.230396] usbcore: registered new interface driver hiddev [ 20.246280] input: Logitech USB Mouse as /devices/pci0000:00/0000:00:1d.1/usb3/3-1/3-1:1.0/input/input6 [ 20.246438] generic-usb 0003:046D:C00C.0001: input,hidraw0: USB HID v1.10 Mouse [Logitech USB Mouse] on usb-0000:00:1d.1-1/input0 [ 20.246479] usbcore: registered new interface driver usbhid [ 20.246483] usbhid: v2.6:USB HID core driver [ 25.436579] usb-storage: device scan complete [ 25.437674] usb-storage: device scan complete

    Read the article

  • WebLogic Server Performance and Tuning: Part I - Tuning JVM

    - by Gokhan Gungor
    Each WebLogic Server instance runs in its own dedicated Java Virtual Machine (JVM) which is their runtime environment. Every Admin Server in any domain executes within a JVM. The same also applies for Managed Servers. WebLogic Server can be used for a wide variety of applications and services which uses the same runtime environment and resources. Oracle WebLogic ships with 2 different JVM, HotSpot and JRocket but you can choose which JVM you want to use. JVM is designed to optimize itself however it also provides some startup options to make small changes. There are default values for its memory and garbage collection. In real world, you will not want to stick with the default values provided by the JVM rather want to customize these values based on your applications which can produce large gains in performance by making small changes with the JVM parameters. We can tell the garbage collector how to delete garbage and we can also tell JVM how much space to allocate for each generation (of java Objects) or for heap. Remember during the garbage collection no other process is executed within the JVM or runtime, which is called STOP THE WORLD which can affect the overall throughput. Each JVM has its own memory segment called Heap Memory which is the storage for java Objects. These objects can be grouped based on their age like young generation (recently created objects) or old generation (surviving objects that have lived to some extent), etc. A java object is considered garbage when it can no longer be reached from anywhere in the running program. Each generation has its own memory segment within the heap. When this segment gets full, garbage collector deletes all the objects that are marked as garbage to create space. When the old generation space gets full, the JVM performs a major collection to remove the unused objects and reclaim their space. A major garbage collect takes a significant amount of time and can affect system performance. When we create a managed server either on the same machine or on remote machine it gets its initial startup parameters from $DOMAIN_HOME/bin/setDomainEnv.sh/cmd file. By default two parameters are set:     Xms: The initial heapsize     Xmx: The max heapsize Try to set equal initial and max heapsize. The startup time can be a little longer but for long running applications it will provide a better performance. When we set -Xms512m -Xmx1024m, the physical heap size will be 512m. This means that there are pages of memory (in the state of the 512m) that the JVM does not explicitly control. It will be controlled by OS which could be reserve for the other tasks. In this case, it is an advantage if the JVM claims the entire memory at once and try not to spend time to extend when more memory is needed. Also you can use -XX:MaxPermSize (Maximum size of the permanent generation) option for Sun JVM. You should adjust the size accordingly if your application dynamically load and unload a lot of classes in order to optimize the performance. You can set the JVM options/heap size from the following places:     Through the Admin console, in the Server start tab     In the startManagedWeblogic script for the managed servers     $DOMAIN_HOME/bin/startManagedWebLogic.sh/cmd     JAVA_OPTIONS="-Xms1024m -Xmx1024m" ${JAVA_OPTIONS}     In the setDomainEnv script for the managed servers and admin server (domain wide)     USER_MEM_ARGS="-Xms1024m -Xmx1024m" When there is free memory available in the heap but it is too fragmented and not contiguously located to store the object or when there is actually insufficient memory we can get java.lang.OutOfMemoryError. We should create Thread Dump and analyze if that is possible in case of such error. The second option we can use to produce higher throughput is to garbage collection. We can roughly divide GC algorithms into 2 categories: parallel and concurrent. Parallel GC stops the execution of all the application and performs the full GC, this generally provides better throughput but also high latency using all the CPU resources during GC. Concurrent GC on the other hand, produces low latency but also low throughput since it performs GC while application executes. The JRockit JVM provides some useful command-line parameters that to control of its GC scheme like -XgcPrio command-line parameter which takes the following options; XgcPrio:pausetime (To minimize latency, parallel GC) XgcPrio:throughput (To minimize throughput, concurrent GC ) XgcPrio:deterministic (To guarantee maximum pause time, for real time systems) Sun JVM has similar parameters (like  -XX:UseParallelGC or -XX:+UseConcMarkSweepGC) to control its GC scheme. We can add -verbosegc -XX:+PrintGCDetails to monitor indications of a problem with garbage collection. Try configuring JVM’s of all managed servers to execute in -server mode to ensure that it is optimized for a server-side production environment.

    Read the article

  • Simple Java networking game engine [on hold]

    - by Florian Peschka
    I want to create a simple java networking game and search a networking engine that eases use of sockets etc. I have already read some questions on here and the internet about java networking for games, but many of them were over 10 years old or not really answered. I have no idea whatsoever about what exactly I need to send in terms of messages, but I figured simple strings or integers will be enough for my purposes. It's basically a peer to peer game, so I don't need a centralized server structure. Messaging doesn't have to have an extremely low ping, yet of course all players need to have a synchronized view. What are the possibilities I have here?

    Read the article

  • Win a set of Infragistics Silverlight Controls with Data Visualization!

    - by mbcrump
    Infragistics recently released their new Silverlight Data Visualization Controls. I saw a couple of samples and had to take a look. I headed over to their website and downloaded the controls. I first noticed the hospital floor-plan demo shown on their site and started thinking of ways that I could use this in my own organization. I emailed them asking if I could give away the Silverlight Data Visualization controls on my site and they said, Yes! They also wanted to throw in the standard Silverlight Line of Business controls. (combined they are worth about $3000 US). I am very thankful they were willing to help the Silverlight community with this giveaway. So some quick rules below: ----------------------------------------------------------------------------------------------------------------------------------------------------------- Win a FREE developer’s license of Infragistics Silverlight Controls with Data Visualization ($3000 Value) Random winner will be announced on January 1st, 2011! To be entered into the contest do the following things: Subscribe to my feed. Leave a comment below with a valid email account (I WILL NOT share this info with anyone.) For extra entries simply: Retweet a link to this page using the following URL [ http://mcrump.me/iscfree ]. It does not matter what the tweet says, just as long as the URL is the same. Unlimited tweets, but please don’t go crazy! This URL will allow me to track the users that Tweet this page. Don’t forget to visit Infragistics because they made this possible. ---------------------------------------------------------------------------------------------------------------------------------------------------------- Before we get started with the Silverlight Controls, here is a couple of links to bookmark: The Silverlight Line of Business Control page is here. You can also check out the live demos here. The Data Visualization page is here. You can also check out the live demos here. Don’t worry about the Samples/Help Documentation. You can install all of that to your local HDD when you are installing it. I am going to walk you through the Silverlight Controls recently released by Infragistics. Begin by downloading the trial version and running the executable. If you downloaded the Complete bundle then you will have the following options to pick from. I like having help documentation and samples on my local HDD in case I do not have access to the internet and want to code. After it is installed, you may want to take a look at your Toolbox in Visual Studio 2010. Look for NetAdvantage 10.3 Silverlight and you will see that you now have access to all of these controls. At this point, to use the controls it’s as simple as drag/drop onto your Silverlight container. It will create the proper Namespaces for you. I wanted to highlight a few of the controls that I liked the most: Grid – After using the Infragistics grid you will wonder how you ever survived using the grid supplied by Microsoft standard controls.  This grid was designed to get your application up and running very fast. It’s simple to bind, it handles LARGE DataSets, easy to filter and allows endless possibilities of formatting data. The screenshot below is an example of the grid. For a real-time updating demo click here. SpellChecker- If your users are creating emails or performing any other function that requires Spell Checking then this control is great. Check out the screenshots below: In this first screen, I have a word that is not in the dictionary [DotNet]. The Spell Checker finds the word and allows the user to correct it. What is so great about Infragistics controls is that it only takes a few lines of code to have a full-featured Spell Checker in your application. TagCloud – This is a control that I haven’t seen anywhere else. It allows you to create keywords for popular search terms. This is very similar to TagCloud seen all over the internet.  Below is a screenshot that shows “Facebook” being a very popular item in the cloud. You can link these items to a hyperlink if you wanted. Importing/Exporting from Excel – I work with data a majority of the time. We all know the importance of Excel in our organizations, its used a lot. With Infragistics controls it make importing and exporting data from a Grid into Excel a snap. One of the things that I liked most about this control was the option to choose the Excel format (2003 or 2007). I haven’t seen this feature in other controls. Creating/Saving/Extracting/Uploading Zip Files – This is another control that I haven’t seen many others making. It allows you to basically manipulate a zip file in any way you like. You can even create a password on the zip file. Schedule – The Schedule that Infragistics provides resembles Outlook’s calendar. I think that it’s important for a user to see your app for the first time and immediately be able to start using because they are already familiar with the UI. The Schedule control accomplishes that in my opinion. I have just barely scratched the surface with the Infragistics Silverlight Line of Business controls. To check all of them then click here. A quick thing to note is that this giveaway also comes with the following Silverlight Data Visualization Controls. Below is a screenshot that list all of them:   I wanted to highlight 2 of the controls that I liked the most: xamBarcode– The xamBarcode supports the following Symbologies: Below is an example of the barcode generated by Infragistics controls. This is a high resolution barcode that you will not have to wonder if your scanner can read it. As long as you have ink in your printer your barcode will read it. I used a Symbol barcode reader to test this barcode. xamTreemap– I’ve never seen a way of displaying data like this before, but I like it. You can style this anyway that you like of course and it also comes with an Office 2010 Theme. Thanks to Infragistics for providing the controls to one lucky reader. I hope that you enjoyed this post and good luck to those that entered the contest.  Subscribe to my feed

    Read the article

  • What You Said: What’s on Your Geeky Christmas List

    - by Jason Fitzpatrick
    Earlier this week we asked you to share what’s on your geeky Christmas list; you responded and we’re back to share your longed for tech goodies. The most requested item was this year’s hot introduction to the project board market: the Raspberry Pi. Dave writes: A Rapsberry Pi to tinker with, especially to see if I can get it up and running with OpenElec/Raspbmc and a torrent client for a low power media centre/htpc We just finished setting up a batch of new 512MB Raspberry Pi systems running the newest release of Rasbmbc and can’t recommend it enough–new refinements in Raspbmc and the extra 256MB of RAM really improve the media center experience. All John wants is a real keyboard so he can escape the torture of using a touch screen: How to Factory Reset Your Android Phone or Tablet When It Won’t Boot Our Geek Trivia App for Windows 8 is Now Available Everywhere How To Boot Your Android Phone or Tablet Into Safe Mode

    Read the article

  • Is there any good tutorial on Apache Jelly?

    - by Vigneshwaran
    I want to write a Jenkins Plugin which requires some knowledge on Apache Jelly. I looked at the Apache Site. It says "Low activity of developers" at the top. They have this tutorial page http://commons.apache.org/jelly/tutorial.html If I click any link to sample code, it gives me a 404 Not Found error. I couldn't find any other tutorial. Please point me to a good tutorial if there is any. Thanks a lot. (PS. Please add Tag Jelly)

    Read the article

  • How can I find the approximate daily traffic of a site which I don't own?

    - by John Thomas
    I want to find the approximate daily traffic of a site which isn't ours, and the site is located in other country than US (in Greece - hence no Quantcast or Compete.com afaik) and it doesn't use Google Ads (hence no Google Ad Planner). I know about Alexa but the site(s) has/have relatively low traffic and the Alexa's rank isn't very useful (same stands to Google Trends). Or perhaps I should look more at Alexa's data? Any other ideas? PS: I looked before posting here and here. No luck.

    Read the article

  • NoSQL Memcached API for MySQL: Latest Updates

    - by Mat Keep
    With data volumes exploding, it is vital to be able to ingest and query data at high speed. For this reason, MySQL has implemented NoSQL interfaces directly to the InnoDB and MySQL Cluster (NDB) storage engines, which bypass the SQL layer completely. Without SQL parsing and optimization, Key-Value data can be written directly to MySQL tables up to 9x faster, while maintaining ACID guarantees. In addition, users can continue to run complex queries with SQL across the same data set, providing real-time analytics to the business or anonymizing sensitive data before loading to big data platforms such as Hadoop, while still maintaining all of the advantages of their existing relational database infrastructure. This and more is discussed in the latest Guide to MySQL and NoSQL where you can learn more about using the APIs to scale new generations of web, cloud, mobile and social applications on the world's most widely deployed open source database The native Memcached API is part of the MySQL 5.6 Release Candidate, and is already available in the GA release of MySQL Cluster. By using the ubiquitous Memcached API for writing and reading data, developers can preserve their investments in Memcached infrastructure by re-using existing Memcached clients, while also eliminating the need for application changes. Speed, when combined with flexibility, is essential in the world of growing data volumes and variability. Complementing NoSQL access, support for on-line DDL (Data Definition Language) operations in MySQL 5.6 and MySQL Cluster enables DevOps teams to dynamically update their database schema to accommodate rapidly changing requirements, such as the need to capture additional data generated by their applications. These changes can be made without database downtime. Using the Memcached interface, developers do not need to define a schema at all when using MySQL Cluster. Lets look a little more closely at the Memcached implementations for both InnoDB and MySQL Cluster. Memcached Implementation for InnoDB The Memcached API for InnoDB is previewed as part of the MySQL 5.6 Release Candidate. As illustrated in the following figure, Memcached for InnoDB is implemented via a Memcached daemon plug-in to the mysqld process, with the Memcached protocol mapped to the native InnoDB API. Figure 1: Memcached API Implementation for InnoDB With the Memcached daemon running in the same process space, users get very low latency access to their data while also leveraging the scalability enhancements delivered with InnoDB and a simple deployment and management model. Multiple web / application servers can remotely access the Memcached / InnoDB server to get direct access to a shared data set. With simultaneous SQL access, users can maintain all the advanced functionality offered by InnoDB including support for Foreign Keys, XA transactions and complex JOIN operations. Benchmarks demonstrate that the NoSQL Memcached API for InnoDB delivers up to 9x higher performance than the SQL interface when inserting new key/value pairs, with a single low-end commodity server supporting nearly 70,000 Transactions per Second. Figure 2: Over 9x Faster INSERT Operations The delivered performance demonstrates MySQL with the native Memcached NoSQL interface is well suited for high-speed inserts with the added assurance of transactional guarantees. You can check out the latest Memcached / InnoDB developments and benchmarks here You can learn how to configure the Memcached API for InnoDB here Memcached Implementation for MySQL Cluster Memcached API support for MySQL Cluster was introduced with General Availability (GA) of the 7.2 release, and joins an extensive range of NoSQL interfaces that are already available for MySQL Cluster Like Memcached, MySQL Cluster provides a distributed hash table with in-memory performance. MySQL Cluster extends Memcached functionality by adding support for write-intensive workloads, a full relational model with ACID compliance (including persistence), rich query support, auto-sharding and 99.999% availability, with extensive management and monitoring capabilities. All writes are committed directly to MySQL Cluster, eliminating cache invalidation and the overhead of data consistency checking to ensure complete synchronization between the database and cache. Figure 3: Memcached API Implementation with MySQL Cluster Implementation is simple: 1. The application sends reads and writes to the Memcached process (using the standard Memcached API). 2. This invokes the Memcached Driver for NDB (which is part of the same process) 3. The NDB API is called, providing for very quick access to the data held in MySQL Cluster’s data nodes. The solution has been designed to be very flexible, allowing the application architect to find a configuration that best fits their needs. It is possible to co-locate the Memcached API in either the data nodes or application nodes, or alternatively within a dedicated Memcached layer. The benefit of this flexible approach to deployment is that users can configure behavior on a per-key-prefix basis (through tables in MySQL Cluster) and the application doesn’t have to care – it just uses the Memcached API and relies on the software to store data in the right place(s) and to keep everything synchronized. Using Memcached for Schema-less Data By default, every Key / Value is written to the same table with each Key / Value pair stored in a single row – thus allowing schema-less data storage. Alternatively, the developer can define a key-prefix so that each value is linked to a pre-defined column in a specific table. Of course if the application needs to access the same data through SQL then developers can map key prefixes to existing table columns, enabling Memcached access to schema-structured data already stored in MySQL Cluster. Conclusion Download the Guide to MySQL and NoSQL to learn more about NoSQL APIs and how you can use them to scale new generations of web, cloud, mobile and social applications on the world's most widely deployed open source database See how to build a social app with MySQL Cluster and the Memcached API from our on-demand webinar or take a look at the docs Don't hesitate to use the comments section below for any questions you may have 

    Read the article

  • Big Data – Role of Cloud Computing in Big Data – Day 11 of 21

    - by Pinal Dave
    In yesterday’s blog post we learned the importance of the NewSQL. In this article we will understand the role of Cloud in Big Data Story What is Cloud? Cloud is the biggest buzzword around from last few years. Everyone knows about the Cloud and it is extremely well defined online. In this article we will discuss cloud in the context of the Big Data. Cloud computing is a method of providing a shared computing resources to the application which requires dynamic resources. These resources include applications, computing, storage, networking, development and various deployment platforms. The fundamentals of the cloud computing are that it shares pretty much share all the resources and deliver to end users as a service.  Examples of the Cloud Computing and Big Data are Google and Amazon.com. Both have fantastic Big Data offering with the help of the cloud. We will discuss this later in this blog post. There are two different Cloud Deployment Models: 1) The Public Cloud and 2) The Private Cloud Public Cloud Public Cloud is the cloud infrastructure build by commercial providers (Amazon, Rackspace etc.) creates a highly scalable data center that hides the complex infrastructure from the consumer and provides various services. Private Cloud Private Cloud is the cloud infrastructure build by a single organization where they are managing highly scalable data center internally. Here is the quick comparison between Public Cloud and Private Cloud from Wikipedia:   Public Cloud Private Cloud Initial cost Typically zero Typically high Running cost Unpredictable Unpredictable Customization Impossible Possible Privacy No (Host has access to the data Yes Single sign-on Impossible Possible Scaling up Easy while within defined limits Laborious but no limits Hybrid Cloud Hybrid Cloud is the cloud infrastructure build with the composition of two or more clouds like public and private cloud. Hybrid cloud gives best of the both the world as it combines multiple cloud deployment models together. Cloud and Big Data – Common Characteristics There are many characteristics of the Cloud Architecture and Cloud Computing which are also essentially important for Big Data as well. They highly overlap and at many places it just makes sense to use the power of both the architecture and build a highly scalable framework. Here is the list of all the characteristics of cloud computing important in Big Data Scalability Elasticity Ad-hoc Resource Pooling Low Cost to Setup Infastructure Pay on Use or Pay as you Go Highly Available Leading Big Data Cloud Providers There are many players in Big Data Cloud but we will list a few of the known players in this list. Amazon Amazon is arguably the most popular Infrastructure as a Service (IaaS) provider. The history of how Amazon started in this business is very interesting. They started out with a massive infrastructure to support their own business. Gradually they figured out that their own resources are underutilized most of the time. They decided to get the maximum out of the resources they have and hence  they launched their Amazon Elastic Compute Cloud (Amazon EC2) service in 2006. Their products have evolved a lot recently and now it is one of their primary business besides their retail selling. Amazon also offers Big Data services understand Amazon Web Services. Here is the list of the included services: Amazon Elastic MapReduce – It processes very high volumes of data Amazon DynammoDB – It is fully managed NoSQL (Not Only SQL) database service Amazon Simple Storage Services (S3) – A web-scale service designed to store and accommodate any amount of data Amazon High Performance Computing – It provides low-tenancy tuned high performance computing cluster Amazon RedShift – It is petabyte scale data warehousing service Google Though Google is known for Search Engine, we all know that it is much more than that. Google Compute Engine – It offers secure, flexible computing from energy efficient data centers Google Big Query – It allows SQL-like queries to run against large datasets Google Prediction API – It is a cloud based machine learning tool Other Players Besides Amazon and Google we also have other players in the Big Data market as well. Microsoft is also attempting Big Data with the Cloud with Microsoft Azure. Additionally Rackspace and NASA together have initiated OpenStack. The goal of Openstack is to provide a massively scaled, multitenant cloud that can run on any hardware. Thing to Watch The cloud based solutions provides a great integration with the Big Data’s story as well it is very economical to implement as well. However, there are few things one should be very careful when deploying Big Data on cloud solutions. Here is a list of a few things to watch: Data Integrity Initial Cost Recurring Cost Performance Data Access Security Location Compliance Every company have different approaches to Big Data and have different rules and regulations. Based on various factors, one can implement their own custom Big Data solution on a cloud. Tomorrow In tomorrow’s blog post we will discuss about various Operational Databases supporting Big Data. Reference: Pinal Dave (http://blog.sqlauthority.com) Filed under: Big Data, PostADay, SQL, SQL Authority, SQL Query, SQL Server, SQL Tips and Tricks, T SQL

    Read the article

  • Wifi connection frequently dropping in hotspots and university campus, home Wifi works fine.

    - by Olivier Lalonde
    For some reason, my Wifi connection frequently drops everywhere except at home. I didn't have this problem with Windows 7 so I guess it's not a hardware problem. My best guess so far is that my connection timeout is very low so if my connection isn't able to reach the router after a few second, the connection drops. Is that likely to be the problem? If so, how could I fix this? Otherwise, what would be an alternative cause for this strange behavior?

    Read the article

  • NET Math Libraries

    - by JoshReuben
    NET Mathematical Libraries   .NET Builder for Matlab The MathWorks Inc. - http://www.mathworks.com/products/netbuilder/ MATLAB Builder NE generates MATLAB based .NET and COM components royalty-free deployment creates the components by encrypting MATLAB functions and generating either a .NET or COM wrapper around them. .NET/Link for Mathematica www.wolfram.com a product that 2-way integrates Mathematica and Microsoft's .NET platform call .NET from Mathematica - use arbitrary .NET types directly from the Mathematica language. use and control the Mathematica kernel from a .NET program. turns Mathematica into a scripting shell to leverage the computational services of Mathematica. write custom front ends for Mathematica or use Mathematica as a computational engine for another program comes with full source code. Leverages MathLink - a Wolfram Research's protocol for sending data and commands back and forth between Mathematica and other programs. .NET/Link abstracts the low-level details of the MathLink C API. Extreme Optimization http://www.extremeoptimization.com/ a collection of general-purpose mathematical and statistical classes built for the.NET framework. It combines a math library, a vector and matrix library, and a statistics library in one package. download the trial of version 4.0 to try it out. Multi-core ready - Full support for Task Parallel Library features including cancellation. Broad base of algorithms covering a wide range of numerical techniques, including: linear algebra (BLAS and LAPACK routines), numerical analysis (integration and differentiation), equation solvers. Mathematics leverages parallelism using .NET 4.0's Task Parallel Library. Basic math: Complex numbers, 'special functions' like Gamma and Bessel functions, numerical differentiation. Solving equations: Solve equations in one variable, or solve systems of linear or nonlinear equations. Curve fitting: Linear and nonlinear curve fitting, cubic splines, polynomials, orthogonal polynomials. Optimization: find the minimum or maximum of a function in one or more variables, linear programming and mixed integer programming. Numerical integration: Compute integrals over finite or infinite intervals, over 2D and higher dimensional regions. Integrate systems of ordinary differential equations (ODE's). Fast Fourier Transforms: 1D and 2D FFT's using managed or fast native code (32 and 64 bit) BigInteger, BigRational, and BigFloat: Perform operations with arbitrary precision. Vector and Matrix Library Real and complex vectors and matrices. Single and double precision for elements. Structured matrix types: including triangular, symmetrical and band matrices. Sparse matrices. Matrix factorizations: LU decomposition, QR decomposition, singular value decomposition, Cholesky decomposition, eigenvalue decomposition. Portability and performance: Calculations can be done in 100% managed code, or in hand-optimized processor-specific native code (32 and 64 bit). Statistics Data manipulation: Sort and filter data, process missing values, remove outliers, etc. Supports .NET data binding. Statistical Models: Simple, multiple, nonlinear, logistic, Poisson regression. Generalized Linear Models. One and two-way ANOVA. Hypothesis Tests: 12 14 hypothesis tests, including the z-test, t-test, F-test, runs test, and more advanced tests, such as the Anderson-Darling test for normality, one and two-sample Kolmogorov-Smirnov test, and Levene's test for homogeneity of variances. Multivariate Statistics: K-means cluster analysis, hierarchical cluster analysis, principal component analysis (PCA), multivariate probability distributions. Statistical Distributions: 25 29 continuous and discrete statistical distributions, including uniform, Poisson, normal, lognormal, Weibull and Gumbel (extreme value) distributions. Random numbers: Random variates from any distribution, 4 high-quality random number generators, low discrepancy sequences, shufflers. New in version 4.0 (November, 2010) Support for .NET Framework Version 4.0 and Visual Studio 2010 TPL Parallellized – multicore ready sparse linear program solver - can solve problems with more than 1 million variables. Mixed integer linear programming using a branch and bound algorithm. special functions: hypergeometric, Riemann zeta, elliptic integrals, Frensel functions, Dawson's integral. Full set of window functions for FFT's. Product  Price Update subscription Single Developer License $999  $399  Team License (3 developers) $1999  $799  Department License (8 developers) $3999  $1599  Site License (Unlimited developers in one physical location) $7999  $3199    NMath http://www.centerspace.net .NET math and statistics libraries matrix and vector classes random number generators Fast Fourier Transforms (FFTs) numerical integration linear programming linear regression curve and surface fitting optimization hypothesis tests analysis of variance (ANOVA) probability distributions principal component analysis cluster analysis built on the Intel Math Kernel Library (MKL), which contains highly-optimized, extensively-threaded versions of BLAS (Basic Linear Algebra Subroutines) and LAPACK (Linear Algebra PACKage). Product  Price Update subscription Single Developer License $1295 $388 Team License (5 developers) $5180 $1554   DotNumerics http://www.dotnumerics.com/NumericalLibraries/Default.aspx free DotNumerics is a website dedicated to numerical computing for .NET that includes a C# Numerical Library for .NET containing algorithms for Linear Algebra, Differential Equations and Optimization problems. The Linear Algebra library includes CSLapack, CSBlas and CSEispack, ports from Fortran to C# of LAPACK, BLAS and EISPACK, respectively. Linear Algebra (CSLapack, CSBlas and CSEispack). Systems of linear equations, eigenvalue problems, least-squares solutions of linear systems and singular value problems. Differential Equations. Initial-value problem for nonstiff and stiff ordinary differential equations ODEs (explicit Runge-Kutta, implicit Runge-Kutta, Gear's BDF and Adams-Moulton). Optimization. Unconstrained and bounded constrained optimization of multivariate functions (L-BFGS-B, Truncated Newton and Simplex methods).   Math.NET Numerics http://numerics.mathdotnet.com/ free an open source numerical library - includes special functions, linear algebra, probability models, random numbers, interpolation, integral transforms. A merger of dnAnalytics with Math.NET Iridium in addition to a purely managed implementation will also support native hardware optimization. constants & special functions complex type support real and complex, dense and sparse linear algebra (with LU, QR, eigenvalues, ... decompositions) non-uniform probability distributions, multivariate distributions, sample generation alternative uniform random number generators descriptive statistics, including order statistics various interpolation methods, including barycentric approaches and splines numerical function integration (quadrature) routines integral transforms, like fourier transform (FFT) with arbitrary lengths support, and hartley spectral-space aware sequence manipulation (signal processing) combinatorics, polynomials, quaternions, basic number theory. parallelized where appropriate, to leverage multi-core and multi-processor systems fully managed or (if available) using native libraries (Intel MKL, ACMS, CUDA, FFTW) provides a native facade for F# developers

    Read the article

  • list of things to think about for hosting a potentially high traffic website

    - by SpashHit
    I do my own hosting for a few clients on my own VPS server (Lindode). Since my clients so far have been extremely low traffic, I have not had to really dig into some of the considerations that I would need for a higher traffic site. Now I am bidding on a client whose site will be potentially higher (not Facebook or twitter, but higher than Joe's ice cream shop). Is there a list of things I need to think about that I may be missing? I am going to assume, at least at first, that I will be able to handle them on my shared Linode, but I could move to a dedicated Linode if need be. I am not thinking so far of multiple servers, but short of that there are still considerations. For example, mod_perl instead of straight CGI, better backups, etc. What else? In case it matters, the stack will be debian-linux / apache / Perl / mysql / Template Toolkit.

    Read the article

  • CQRS - Benefits

    - by Dylan Smith
    Thanks to all the comments and feedback from the last post I think I have a better understanding now of the benefits of CQRS (separate from the benefits of Event Sourcing). I’m going to try and sum it up here, and point out some areas where I could still use some advice: CQRS Benefits Sounds like the primary benefit of CQRS as an architecture is it allows you to create a simpler domain model by sucking out everything related to queries. I can definitely see the benefit to this, in general the domain logic related to commands is the high-value behavior in the software, but the logic required to service the queries would add a lot of low-value “noise” to the domain model that would dilute the high-value (command) behavior – sorting, paging, filtering, pre-fetch paths, etc. Also the most appropriate domain structure for implementing commands might not be the most optimal for implementing queries. To paraphrase Greg, this usually results in a domain model that is mediocre at both, piss-poor at one, or more likely piss-poor at both commands and queries. Not only will you be able to simplify your domain model by pulling out all the query logic, but at least a handful of commands in most systems will probably be “pass-though” type commands with little to no logic that just generate events. If these can be implemented directly in the command-handler and never touch the domain model, this allows you to slim down the domain model even more. Also, if you were to do event sourcing without CQRS, you no longer have a database containing the current state (only the domain model would) which makes it difficult (or impossible) to support ad-hoc querying and/or reporting that is common in most business software. Of course CQRS provides some great scalability benefits, not only scalability but I have to assume that it provides extremely low latency for most operations, especially if you have an asynchronous event bus. I know Greg says that you get a 3x scaling (Commands, Queries, Client) of your ability to perform parallel development, but IMHO, it seems like it only provides 1.5x scaling since even without CQRS you’re going to have your client loosely coupled to your domain - which is still a great benefit to be able to realize. Questions / Concerns If all the queries against an aggregate get pulled out to the Query layer, what if the only commands for that aggregate can be handled in a “pass-through” manner with the command handler directly generating events. Is it possible to have an aggregate that isn’t modeled in the domain model? Are there any issues or downsides to this? I know in the feedback from my previous posts it was suggested that having one domain model handling both commands and queries requires implementing a lot of traversals between objects that wouldn’t be necessary if it was only servicing commands. My question is, do you include traversals in your domain model based on the needs of the code, or based on the conceptual domain model? If none of my Commands require a Customer.Orders traversal, but the conceptual domain includes the concept of a set of orders belonging to a customer – should I model that in my domain model or not? I like the idea of using the Query side of the architecture as a place to put junior devs where the risk of them screwing something up has minimal impact. But I’m not sold on the idea that you can actually outsource it. Like I said in one of my comments on my previous post, the code to handle a query and generate DTO’s is going to be dead simple, but the code to process events and apply them to the tables on the query side is going to require a significant amount of domain knowledge to know which events to listen for to update each of the de-normalized tables (and what changes need to be made when each event is processed). I don’t know about everybody else, but having Indian/Russian/whatever outsourced developers have to do anything that requires significant domain knowledge has never been successful in my experience. And if you need to spec out for each new query which events to listen to and what to do with each one, well that’s probably going to be just as much work to document as it would be to just implement it. Greg made the point in a comment that doing an aggregate query like “Total Sales By Customer” is going to be inefficient if you use event sourcing but not CQRS. I don’t understand why that would be the case. I imagine in that case you’d simply have a method/property on the Customer object that calculated total sales for that customer by enumerating over the Orders collection. Then the application services layer would generate DTO’s off of the Customers collection that included say the CustomerID, CustomerName, TotalSales, or whatever the case may be. As long as you use a snapshotting implementation, I don’t see why that would be anymore inefficient in a DDD+Event Sourcing implementation than in a typical DDD implementation. Like I mentioned in my last post I still have some questions about query logic that haven’t been answered yet, but before I start asking those I want to make sure I have a strong grasp on what benefits CQRS provides.  My main concern with the query logic was that I know I could just toss it all into the query side, but I was concerned that I would be losing the benefits of using CQRS in the first place if I did that.  I want to elaborate more on this though with some example situations in an upcoming post.

    Read the article

  • Pyglet vs. PyQt

    - by L. De Leo
    I need to implement a really simple card game. As the game logic is written in Python I chose to stick with some Python framework even if my goal is to develop a Windows only version. I also don't like to work with .NET so I ruled out Iron Python + WPF. I tried to write a simple prototype with Pyglet but soon discovered that I will have to do a lot of stuff by hand: things like detecting mouseover events and finding which card was clicked on and moving it, etc... very low level and unnecessary for my use-case. So I thought it might be easier to do things in PyQt. Do you reckon it would be feasible to use PyQt for implementing a simple card game? Will I have higher level events I can work with?

    Read the article

  • Why isn't SSL/TLS built into modern Operating Systems?

    - by Channel72
    A lot of the basic network protocols that make up the infrastructure of the Internet are built in to most major Operating Systems. Things like TCP, UDP, and DNS are all built into Linux, UNIX and Windows, and are made available to the programmer through low-level system APIs. But when it comes to SSL or TLS, one has to turn to a third-party library such as OpenSSL or Mozilla NSS. SSL is a relatively old protocol, and it's basically an industry standard as ubiquitous as TCP/IP, so why isn't it built into most Operating Systems?

    Read the article

  • Can't Boot, video drivers or x-server problem?

    - by ZacharyH
    I was uninstalling some programs that I installed to try and get my iPod touch working with Ubuntu (I gave up on that) when ubuntu just crashed. Now after I choose ubuntu in GRUB, it gives me a screen that says "Ubuntu is running in low-graphics mode: your screen, graphics card, and input device settings could not be detected correctly. You will need to configure these yourself" It was working just fine before I started to uninstall those programs. I think that I might have uninstalled something necessary to the system. If I click OK on the screen, it gives me options to reconfigure, troubleshoot, exit to console, or restart X. But no matter what I choose I still can't boot into ubuntu - I get stuck looking at the splash screen which stalls forever. I was receiving support from one of my mate's and he was doing something with the LiveCD, and now the message doesn't pop up any more, I just get stuck at a never ending splash screen. Any help would be appreciated, thanks!

    Read the article

< Previous Page | 97 98 99 100 101 102 103 104 105 106 107 108  | Next Page >