Search Results

Search found 2726 results on 110 pages for 'processor'.

Page 85/110 | < Previous Page | 81 82 83 84 85 86 87 88 89 90 91 92  | Next Page >

• how to start LXDE session automatically after tightvncserver starts to make me able see desktop when connecting to the host via vncclient?

  - by Oleksandr Dudchenko

  I have system which is equipped with Intel Celeron processor 1.1 GHz s370 with 384 Mb of RAM on Intel d815egew motherboard which supports wake-on-lan function. I want to use such a PC for Internet sharing to the local network. Also this PC is a DHCP+DNS server as well as router/gateway. Based on above I decided to install Lubuntu as it is lightweight system. I installed Lubuntu 10.04.4 LTS from alternate ISO. System has no auto login. System boots and has acceptable performance. Host PC has onboard 4 network adapters: eth0 – ethernet controller which is used for Local Network connections. Has static address 10.0.0.1 eth1 – ethernet controller which is not used and not configured so far, I plan to connect printer here later on. eth2 - ethernet controller which is used to connect to Internet, which we plan to share for the local network wlan0 – wireless controller, it is used in role of access poit for local Network and has address 10.0.0.2 We want to control our gateway remotely. So, we need to be able to power it on remotely. To allow this I’ve done the following things: $ cd /etc/init.d/ made a new file with command $ sudo vim wakeonlanconfig Wrote the following lines to the newly created file, saved and closed it #!/bin/bash ethtool -s eth0 wol g ethtool -s eth2 wol g exit Made the abovementioned file executable $ sudo chmod a+x wakeonlanconfig Then included it into autostart sequence during boot. $ sudo update-rc.d -f wakeonlanconfig defaults after system reboot we will be able to poweron system remotely. Than we need to have a possibility to connect remotely to the host via SSH and VNC. So, I installed following packets with the following commands: $ sudo apt-get update $ sudo apt-get install openssh-server tightvncserver Add ssh daemon into autostart sequence during boot. $ sudo update-rc.d -f ssh defaults Power off the host PC $ sudo halt Then I went to remote place, send magic paket and powered the Host up. System started... And I connected to the host via Putty from remote system under Windows. Than logged in and run the command to start vnc server. $ tightvncserver -geometry 800x600 -depth 16 :2 VNC server successfully started and I got message like follows. New 'X' desktop is gateway:2 Starting applications specified in /home/dolv/.vnc/xstartup Log file is /home/dolv/.vnc/gateway:2.log Using UltraVNC Viewer programm under windows I connected to the host's vnc server, enterd the password and.... sow only mouse cursor in form of cross on a grey background of 800x600 dots, no desktop. Here is my .vnc/xstartup file #!/bin/sh xrdb $HOME/.Xresources xsetroot -solid grey #x-terminal-emulator -geometry 80x24+10+10 -ls -title "$VNCDESKTOP Desktop" & #x-window-manager & # Fix to make GNOME work export XKL_XMODMAP_DISABLE=1 /etc/X11/Xsession The Question: What I have to change and where to make LXDE session start automatically after tightvncserver starts?

  Read the article

• Don Knuth and MMIXAL vs. Chuck Moore and Forth -- Algorithms and Ideal Machines -- was there cross-pollination / influence in their ideas / work?

  - by AKE

  Question: To what extent is it known (or believed) that Chuck Moore and Don Knuth had influence on each other's thoughts on ideal machines, or their work on algorithms? I'm interested in citations, interviews, articles, links, or any other sort of evidence. It could also be evidence of the form of A and B here suggest that Moore might have borrowed or influenced C and D from Knuth here, or vice versa. (Opinions are of course welcome, but references / links would be better!) Context: Until fairly recently, I have been primarily familiar with Knuth's work on algorithms and computing models, mostly through TAOCP but also through his interviews and other writings. However, the more I have been using Forth, the more I am struck by both the power of a stack-based machine model, and the way in which the spareness of the model makes fundamental algorithmic improvements more readily apparent. A lot of what Knuth has done in fundamental analysis of algorithms has, it seems to me, a very similar flavour, and I can easily imagine that in a parallel universe, Knuth might perhaps have chosen Forth as his computing model. That's the software / algorithms / programming side of things. When it comes to "ideal computing machines", Knuth in the 70s came up with the MIX computer model, and then, collaborating with designers of state-of-the-art RISC chips through the 90s, updated this with the modern MMIX model and its attendant assembly language MMIXAL. Meanwhile, Moore, having been using and refining Forth as a language, but using it on top of whatever processor happened to be in the computer he was programming, began to imagine a world in which the efficiency and value of stack-based programming were reflected in hardware. So he went on in the 80s to develop his own stack-based hardware chips, defining the term MISC (Minimal Instruction Set Computers) along the way, and ending up eventually with the first Forth chip, the MuP21. Both are brilliant men with keen insight into the art of programming and algorithms, and both work at the intersection between algorithms, programs, and bare metal hardware (i.e. hardware without the clutter of operating systems). Which leads me to the headlined question... Question:To what extent is it known (or believed) that Chuck Moore and Don Knuth had influence on each other's thoughts on ideal machines, or their work on algorithms?

  Read the article

• Display Driver Issue on an hp TX2-1160ea Notebook

  - by Sam

  I'm new to Linux and recently switched to Ubuntu 11.04 due to my project requirement. My laptop has been freezing and going to black screen of death when I run anything related to display (Share desktop, stream video, etc). Today I went through the Ubuntu forum to install the appropriate graphic driver and, after doing it, I rebooted my PC. It gave an error before login saying "select the recovery mode" and after clicking OK, it didn't give the same error on reboot but I've lost the 11.04 graphical interface and all I see is the interface of Ubuntu v10 with slow visuals (even scrolling up/down on browser is really slow). For the reference, here's a desktop screenshot so that you can understand the situation. Also the laptop is overheating. How can I fix this problem? How can i get the Ubuntu 11.04 view back? I also tried Google, but couldn't find any issue like this. Some general Information: Laptop: HP TouchSmart TX2-1160ea Processor: AMD Turion TX2 Memory: 4GB OS: Ubuntu 11.04 Some debugging information:: $ report-hw | grep controller lspci -knn: 00:11.0 SATA controller [0106]: ATI Technologies Inc SB7x0/SB8x0/SB9x0 SATA Controller [AHCI mode] [1002:4391] lspci -knn: 00:14.3 ISA bridge [0601]: ATI Technologies Inc SB7x0/SB8x0/SB9x0 LPC host controller [1002:439d] lspci -knn: 01:05.0 VGA compatible controller [0300]: ATI Technologies Inc RS780M/RS780MN [Radeon HD 3200 Graphics] [1002:9612] lspci -knn: 08:00.0 Network controller [0280]: Broadcom Corporation BCM4322 802.11a/b/g/n Wireless LAN Controller [14e4:432b] (rev 01) lspci -knn: 09:00.0 Ethernet controller [0200]: Realtek Semiconductor Co., Ltd. RTL8111/8168B PCI Express Gigabit Ethernet controller [10ec:8168] (rev 02) And: $ dpkg -l '*fglrx*' Desired=Unknown/Install/Remove/Purge/Hold | Status=Not/Inst/Conf-files/Unpacked/halF-conf/Half-inst/trig-aWait/Trig-pend |/ Err?=(none)/Reinst-required (Status,Err: uppercase=bad) ||/ Name Version Description +++-==============-==============-============================================ ii fglrx 2:8.840-0ubunt Video driver for the ATI graphics accelerato ii fglrx-amdcccle 2:8.840-0ubunt Catalyst Control Center for the ATI graphics un fglrx-control <none> (no description available) un fglrx-control- <none> (no description available) ii fglrx-dev 2:8.840-0ubunt Video driver for the ATI graphics accelerato un fglrx-driver <none> (no description available) un fglrx-driver-d <none> (no description available) un fglrx-kernel-s <none> (no description available) un fglrx-modalias <none> (no description available) un xfree86-driver <none> (no description available) un xfree86-driver <none> (no description available) un xorg-driver-fg <none> (no description available) un xorg-driver-fg <none> (no description available) If you need any more information that could help, just ask.

  Read the article

• Subterranean IL: Volatile

  - by Simon Cooper

  This time, we'll be having a look at the volatile. prefix instruction, and one of the differences between volatile in IL and C#. The volatile. prefix volatile is a tricky one, as there's varying levels of documentation on it. From what I can see, it has two effects: It prevents caching of the load or store value; rather than reading or writing to a cached version of the memory location (say, the processor register or cache), it forces the value to be loaded or stored at the 'actual' memory location, so it is then immediately visible to other threads. It forces a memory barrier at the prefixed instruction. This ensures instructions don't get re-ordered around the volatile instruction. This is slightly more complicated than it first seems, and only seems to matter on certain architectures. For more details, Joe Duffy has a blog post going into the details. For this post, I'll be concentrating on the first aspect of volatile. Caching field accesses To demonstrate this, I created a simple multithreaded IL program. It boils down to the following code: .class public Holder { .field public static class Holder holder .field public bool stop .method public static specialname void .cctor() { newobj instance void Holder::.ctor() stsfld class Holder Holder::holder ret }}.method private static void Main() { .entrypoint // Thread t = new Thread(new ThreadStart(DoWork)) // t.Start() // Thread.Sleep(2000) // Console.WriteLine("Stopping thread...") ldsfld class Holder Holder::holder ldc.i4.1 stfld bool Holder::stop call instance void [mscorlib]System.Threading.Thread::Join() ret}.method private static void DoWork() { ldsfld class Holder Holder::holder // while (!Holder.holder.stop) {} DoWork: dup ldfld bool Holder::stop brfalse DoWork pop ret} If you compile and run this code, you'll find that the call to Thread.Join() never returns - the DoWork spinlock is reading a cached version of Holder.stop, which is never being updated with the new value set by the Main method. Adding volatile to the ldfld fixes this: dupvolatile.ldfld bool Holder::stopbrfalse DoWork The volatile ldfld forces the field access to read direct from heap memory, which is then updated by the main thread, rather than using a cached copy. volatile in C# This highlights one of the differences between IL and C#. In IL, volatile only applies to the prefixed instruction, whereas in C#, volatile is specified on a field to indicate that all accesses to that field should be volatile (interestingly, there's no mention of the 'no caching' aspect of volatile in the C# spec; it only focuses on the memory barrier aspect). Furthermore, this information needs to be stored within the assembly somehow, as such a field might be accessed directly from outside the assembly, but there's no concept of a 'volatile field' in IL! How this information is stored with the field will be the subject of my next post.

  Read the article

• Error message during update from 13.04 to 13.10

  - by layonhands

  The following was reported after I attempted to report the problem back to Ubuntu: The problem cannot be reported: You have some obsolete package versions installed. Please upgrade the following packages and check if the problem still occurs: ubuntu-release-upgrader-gtk, apport, apport-gtk, apport-symptoms, apt, apt-utils, at-spi2-core, binutils, dbus, gcc-4.7-base, gdb, gir1.2-atk-1.0, gir1.2-gtk-3.0, glib-networking, glib-networking-common, glib-networking-services, gnupg, gpgv, ifupdown, initramfs-tools, initramfs-tools-bin, kmod, libappindicator3-1, libapt-inst1.5, libapt-pkg4.12, libasound2, libatk-bridge2.0-0, libatk1.0-0, libatk1.0-data, libatspi2.0-0, libc-bin, libc6, libcups2, libdbus-1-3, libdbusmenu-glib4, libdbusmenu-gtk3-4, libdrm-intel1, libdrm-nouveau2, libdrm-radeon1, libdrm2, libgail-3-0, libgcc1, libgcrypt11, libglib2.0-0, libglib2.0-data, libgnutls26, libgomp1, libgstreamer-plugins-base1.0-0, libgstreamer1.0-0, libgtk-3-0, libgtk-3-bin, libgtk-3-common, libgudev-1.0-0, libicu48, libindicator3-7, libkmod2, liblcms2-2, libpci3, libplymouth2, libpolkit-agent-1-0, libpolkit-backend-1-0, libpolkit-gobject-1-0, libprocps0, libpython-stdlib, libpython2.7, libpython2.7-minimal, libpython2.7-stdlib, libpython3-stdlib, libpython3.3-minimal, libpython3.3-stdlib, libssl1.0.0, libstdc++6, libtiff5, libudev1, libx11-6, libx11-data, libx11-xcb1, libxcb-dri2-0, libxcb-glx0, libxcb-render0, libxcb-shm0, libxcb1, libxcursor1, libxext6, libxfixes3, libxi6, libxinerama1, libxml2, libxrandr2, libxrender1, libxres1, libxt6, libxtst6, libxxf86vm1, lsb-base, lsb-release, module-init-tools, multiarch-support, openssl, passwd, pciutils, perl, perl-base, perl-modules, plymouth, plymouth-theme-ubuntu-text, policykit-1, procps, python, python-gi, python-minimal, python2.7, python2.7-minimal, python3, python3-apport, python3-distupgrade, python3-gi, python3-minimal, python3-problem-report, python3-software-properties, python3-update-manager, python3.3, python3.3-minimal, rsyslog, shared-mime-info, software-properties-common, software-properties-gtk, tar, tzdata, ubuntu-release-upgrader-core, ubuntu-release-upgrader-gtk, udev, update-manager, update-manager-core, update-notifier, update-notifier-common If this question has already been answered, I'm sorry for the repost, but I would appreciate a link to the fix. Thanks. FYI: Dell Latitude D630, Intel Centrino processor. Also, the updater is currently running what seems to be the update. I will report back when it is done going through its process to let you know if it is in fact the 13.10 update. Update 2: System went through an update, but it wasn't for the OS. I think it was an update for the error message mentioned above. Now the OS update is currently running the 'distribution upgrade' portion of the update. This is further than it had gone before. Again I will report back once this is done to let you know whether or not the update was successful. Final Update: Don't know for sure what happened, but I'm almost sure that the error mentioned above was resolved in the first update prior to the 13.10 update. All set.

  Read the article

• OBIA on Teradata - Part 2 Teradata DB Utilization for ETL

  - by Mohan Ramanuja

  Techniques to Monitor Queries and ETL Load CPU and Disk I/OSelect username, processor, sum(cputime), sum(diskio) from dbc.ampusage where processor ='1-0' order by 2,3 descgroup by 1,2;UserName    Vproc    Sum(CpuTime)    Sum(DiskIO)AC00916        10    6.71            24975 List Hardware ErrorsThere is a possibility that the system might have adequate disk space but out of free cylinders. In order to monitor hardware errors, the following query was used:Select * from dbc.Software_Event_Log where Text like '%restart%' order by thedate, thetime;For active users, usage of CPU and analysis of bad CPU to I/O ratiosSelect * from DBC.AMPUSAGE where username='CRMSTGC_DEV_ID';  AND SUBSTR(ACCOUNTNAME,6,3)='006'; Usage By I/OSelect AccountName, UserName, sum(CpuTime), sum(DiskIO)  from DBC.AMPUSAGE group by AccountName, UserName Order by Sum(DiskIO) desc; AccountName                       UserName                          Sum(CpuTime)  Sum(DiskIO)$M1$10062209                      AB89487                           374628.612    7821847$M1$10062210                      AB89487                           186692.244    2799412$M1$10062213                      COC_ETL_ID                        119531.068    331100426$M1$10062200                      AB63472                           118973.316    109881984$M1$10062204                      AB63472                           110825.356    94666986$M1$10062201                      AB63472                           110797.976    75016994$M1$10062202                      AC06936                           100924.448    407839702$M1$10062204                      AB67963                           0         4$M1$10062207                      AB91990                           0         2$M1$10062208                      AB63461                           0         24$M1$10062211                      AB84332                           0         6$M1$10062214                      AB65484                           0         8$M1$10062205                      AB77529                           0         58$M1$10062210                      AC04768                           0         36$M1$10062206                      AB54940                           0         22 Usage By CPUSelect AccountName, UserName, sum(CpuTime), sum(DiskIO)  from DBC.AMPUSAGE group by AccountName, UserName Order by Sum(CpuTime) desc;AccountName                       UserName                          Sum(CpuTime)  Sum(DiskIO)$M1$10062209                      AB89487                           374628.612    7821847$M1$10062210                      AB89487                           186692.244    2799412$M1$10062213                      COC_ETL_ID                        119531.068    331100426$M1$10062200                      AB63472                           118973.316    109881984$M1$10062204                      AB63472                           110825.356    94666986$M1$10062201                      AB63472                           110797.976    75016994$M2$100622105813004760047LOAD     T23_ETLPROC_ENT                   0 6$M1$10062215                      AA37720                           0     180$M1$10062209                      AB81670                           0     6Select count(distinct vproc) from dbc.ampusage;432select * from dbc.dbcinfo;AccountName     UserName     CpuTime DiskIO  CpuTimeNorm         Vproc VprocType    Model$M1$10062205                      CRM_STGC_DEV_ID                   0.32    1764    12.7423999023438    0     AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.28    1730    11.1495999145508    3     AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.304    1736    12.1052799072266    4    AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.248    1731    9.87535992431641    7    AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.332    1731    13.2202398986816    8    AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.284    1712    11.3088799133301    11   AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.24    1757    9.55679992675781    12    AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.292    1737    11.6274399108887    15   AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.268    1753    10.6717599182129    16   AMP      2580$M1$10062205                      CRM_STGC_DEV_ID                   0.276    1732    10.9903199157715    19   AMP      2580select * from dbc.dbcinfo;InfoKey    InfoDataLANGUAGE   SUPPORT           MODE    StandardRELEASE    12.00.03.03VERSION    12.00.03.01a

  Read the article

• asus n550jv audio problem: no sound from notebook' speakers

  - by skywalker

  Ubuntu 13.10. The problem is: the internal speakers don't work. I have no problem when I'm using the headphones. There is no hardware issue since in windows 8 everything works perfectly(external subwoofer included). I'm trying to modify /etc/modprobe.d/alsa-base.conf but I can't find the correct model to put into: options snd-hda-intel model= The file HD-Audio-Models.txt doesn't contain the model for ALC668. Some info: :~sudo aplay -l **** List of PLAYBACK Hardware Devices **** card 0: MID [HDA Intel MID], device 3: HDMI 0 [HDMI 0] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: MID [HDA Intel MID], device 7: HDMI 1 [HDMI 1] Subdevices: 1/1 Subdevice #0: subdevice #0 card 0: MID [HDA Intel MID], device 8: HDMI 2 [HDMI 2] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: PCH [HDA Intel PCH], device 0: ALC668 Analog [ALC668 Analog] Subdevices: 0/1 Subdevice #0: subdevice #0 :~$ sudo lspci -v | grep -A7 -i "audio" 00:03.0 Audio device: Intel Corporation Xeon E3-1200 v3/4th Gen Core Processor HD Audio Controller (rev 06) Subsystem: Intel Corporation Device 2010 Flags: bus master, fast devsel, latency 0, IRQ 52 Memory at f7a14000 (64-bit, non-prefetchable) [size=16K] Capabilities: [50] Power Management version 2 Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit- Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00 Kernel driver in use: snd_hda_intel -- 00:1b.0 Audio device: Intel Corporation 8 Series/C220 Series Chipset High Definition Audio Controller (rev 04) Subsystem: ASUSTeK Computer Inc. Device 11cd Flags: bus master, fast devsel, latency 0, IRQ 53 Memory at f7a10000 (64-bit, non-prefetchable) [size=16K] Capabilities: [50] Power Management version 2 Capabilities: [60] MSI: Enable+ Count=1/1 Maskable- 64bit+ Capabilities: [70] Express Root Complex Integrated Endpoint, MSI 00 Capabilities: [100] Virtual Channel PS info :~$ amixer -c 0 Simple mixer control 'IEC958',0 Capabilities: pswitch pswitch-joined Playback channels: Mono Mono: Playback [on] Simple mixer control 'IEC958',1 Capabilities: pswitch pswitch-joined Playback channels: Mono Mono: Playback [on] Simple mixer control 'IEC958',2 Capabilities: pswitch pswitch-joined Playback channels: Mono Mono: Playback [on] :~$ pacmd dump-volumes Welcome to PulseAudio! Use "help" for usage information. Sink 0: reference = 0: 76% 1: 76%, real = 0: 76% 1: 76%, soft = 0: 100% 1: 100%, current_hw = 0: 76% 1: 76%, save = yes Input 8: volume = 0: 100% 1: 100%, reference_ratio = 0: 100% 1: 100%, real_ratio = 0: 100% 1: 100%, soft = 0: 100% 1: 100%, volume_factor = 0: 100% 1: 100%, volume_factor_sink = 0: 100% 1: 100%, save = no Source 0: reference = 0: 100% 1: 100%, real = 0: 100% 1: 100%, soft = 0: 100% 1: 100%, current_hw = 0: 100% 1: 100%, save = no Source 1: reference = 0: 16% 1: 16%, real = 0: 16% 1: 16%, soft = 0: 100% 1: 100%, current_hw = 0: 16% 1: 16%, save = yes

  Read the article

• Gradle for NetBeans RCP

  - by Geertjan

  Start with the NetBeans Paint Application and do the following to build it via Gradle (i.e., no Gradle/NetBeans plugin is needed for the following steps), assuming you've set up Gradle. Do everything below in the Files or Favorites window, not in the Projects window. In the application directory "Paint Application". Create a file named "settings.gradle", with this content: include 'ColorChooser', 'Paint' Create another file in the same location, named "build.gradle", with this content: subprojects { apply plugin: "announce" apply plugin: "java" sourceSets { main { java { srcDir 'src' } resources { srcDir 'src' } } } } In the module directory "Paint". Create a file named "build.gradle", with this content: dependencies { compile fileTree("$rootDir/build/public-package-jars").matching { include '**/*.jar' } } task show << { configurations.compile.each { dep -> println "$dep ${dep.isFile()}" } } Note: The above is a temporary solution, as you can see, the expectation is that the JARs are in the 'build/public-packages-jars' folder, which assumes an Ant build has been done prior to the Gradle build. Now run 'gradle classes' in the "Paint Application" folder and everything will compile correctly. So, this is how the Paint Application now looks: Preferable to the second 'build.gradle' would be this, which uses the JARs found in the NetBeans Platform... netbeansHome = '/home/geertjan/netbeans-dev-201111110600' dependencies { compile files("$rootDir/ColorChooser/release/modules/ext/ColorChooser.jar") def projectXml = new XmlParser().parse("nbproject/project.xml") projectXml.configuration.data."module-dependencies".dependency."code-name-base".each { if (it.text().equals('org.openide.filesystems')) { def dep = "$netbeansHome/platform/core/"+it.text().replace('.','-')+'.jar' compile files(dep) } else if (it.text().equals('org.openide.util.lookup') || it.text().equals('org.openide.util')) { def dep = "$netbeansHome/platform/lib/"+it.text().replace('.','-')+'.jar' compile files(dep) } else { def dep = "$netbeansHome/platform/modules/"+it.text().replace('.','-')+'.jar' compile files(dep) } } } task show << { configurations.compile.each { dep -> println "$dep ${dep.isFile()}" } } However, when you run 'gradle classes' with the above, you get an error like this: geertjan@geertjan:~/NetBeansProjects/PaintApp1/Paint$ gradle classes :Paint:compileJava [ant:javac] Note: Attempting to workaround javac bug #6512707 [ant:javac] [ant:javac] [ant:javac] An annotation processor threw an uncaught exception. [ant:javac] Consult the following stack trace for details. [ant:javac] java.lang.NullPointerException [ant:javac] at com.sun.tools.javac.util.DefaultFileManager.getFileForOutput(DefaultFileManager.java:1058) No idea why the above happens, still trying to figure it out. Once the above works, we can start figuring out how to use the NetBeans Maven repo instead and then the user of the plugin will be able to select whether to use local JARs or JARs from the NetBeans Maven repo. Many thanks to Hans Dockter who put the above together with me today, via Skype!

  Read the article

• Is Infiniband going to get squeezed by iWARP and external QPI?

  - by andy.grover

  The Inquirer certainly thinks so.However, I'm not so sure it makes sense to compare Infiniband to an as-yet-unannounced optical external QPI. QPI is currently a processor interconnect. CPUs, RAM, and devices connected by it are conceptually part of the same machine -- they run a single OS, for example. They are both "networks" or "fabrics" but they have very different design trade-offs.Another widely-used bus in the system is closer to Infiniband than QPI -- PCI Express. Isn't it more likely that PCIe could take on IB? There are companies already who have solutions that use external PCI Express for cluster interconnect, but these have not gained significant market share. Why would QPI, a technology whose sweet spot is even further from Infiniband's than PCIe, be able to challenge Infiniband? It's hard to speculate without much information, but right now it doesn't seem likely to me.The other prediction made in the article is that Intel's 10GbE iWARP card could squeeze IB on the low end, due to its greater compatibility and lower cost.It's definitely never a good idea to bet against Ethernet when it comes to mass-market, commodity networking. Ethernet will win. 10GbE will win. But, there are now two competing ways to implement the low-latency RDMA Verbs interface on top of Ethernet. iWARP is essentially RDMA over TCP/IP over Ethernet. The new alternative is IBoE (Infiniband over Ethernet, aka RoCEE, aka "Rocky"). This encapsulates the IB packet protocol directly in the Ethernet frame. It loses the layer 3 routability of iWARP, but better maintains software compatibility with existing apps that use IB, and is simpler to implement in both software and hardware. iWARP has a substantial head start, but I believe that IBoE silicon will eventually be cheaper, and more likely to be implemented in commodity Ethernet hardware.I think IBoE is going to take low-end market share from traditional IB, but I think this is a situation IB hardware vendors have no problem accepting. Commoditized IBoE NICs invite greater use of RDMA features, and when higher performance is needed, customers can upgrade to "real" IB, maintaining IB's justification for higher prices. (IB max interconnect speeds have historically been 2-4x higher than Ethernet, and I don't see that changing.)(ObDisclosure: My current employer now sells IB hardware. I previously also worked at Intel. My opinions are my own, duh.)

  Read the article

• GPU hung when switching graphic card

  - by Lie Ryan

  I have a laptop (Dell Inspiron N4110) with a switchable graphic. $ lspci | grep VGA 00:02.0 VGA compatible controller: Intel Corporation 2nd Generation Core Processor Family Integrated Graphics Controller (rev 09) 01:00.0 VGA compatible controller: ATI Technologies Inc NI Whistler [AMD Radeon HD 6600M Series] (rev ff) Normally, my laptop starts with both graphic cards enabled, which caused the laptop to turn very hot and the fan to become very noisy. I have been using a small script to disable the Radeon card. For some time, I'm quite happy with this arrangement. However, I have been having some issues with the Intel card (IGD), the Intel card often randomly hang when running OpenGL apps; and so I want to give the Radeon card (DIS) another chance. I have never been able to switch to the Radeon card, but recently, I found out that if I do a "delayed switching" (DDIS): # echo "DDIS" > /sys/kernel/debug/vgaswitcheroo/switch root@lieryan-dell-ubuntu:/sys/kernel/debug/vgaswitcheroo# cat switch 0:IGD:+:Pwr:0000:00:02.0 1:DIS: :Pwr:0000:01:00.0 then I logoff (i.e. to restart X), the screen switch to pseudo-tty and then it stuck there freezing. At this situation, mouse and keyboard stops working so I can't switch to another ptty. I tried ssh-ing from another computer to salvage logs (dmesg at that point) and whatnot; I found out that when freezing, the active graphic card is the AMD card: -- this is from ssh -- # cat switch 0:IGD: :Off:0000:00:02.0 1:DIS:+:Pwr:0000:01:00.0 but the GPU is apparently hung, looking at dmesg gives: ... [ 1411.649974] vga_switcheroo: client 0 refused switch [ 1411.649985] vga_switcheroo: setting delayed switch to client 1 [ 1423.911759] vga_switcheroo: processing delayed switch to 1 [ 1424.006564] fbcon: Remapping primary device, fb1, to tty 1-63 [ 1424.006799] i915: switched off [ 1424.840351] [drm:drm_mode_getfb] *ERROR* invalid framebuffer id [ 1425.718088] [drm:drm_mode_getfb] *ERROR* invalid framebuffer id [ 1426.622377] [drm:drm_mode_getfb] *ERROR* invalid framebuffer id [ 1427.355683] [drm:drm_mode_getfb] *ERROR* invalid framebuffer id [ 1428.193549] [drm:drm_mode_getfb] *ERROR* invalid framebuffer id ... the invalid framebuffer id error is repeated for many times over ... I were able to successfully recover by switching back to the Intel card and restarting X from ssh; indicating that only the Radeon card has problems switching. System info: $ uname -a Linux lieryan-dell-ubuntu 3.0.0-14-generic #23-Ubuntu SMP Mon Nov 21 20:28:43 UTC 2011 x86_64 x86_64 x86_64 GNU/Linux $ lsb_release -a No LSB modules are available. Distributor ID: Ubuntu Description: Ubuntu 11.10 Release: 11.10 Codename: oneiric The laptop also do not have the option to set graphic card at BIOS and the proprietary driver, fglrx, also have never worked; when I installed it through jockey ("Additional Drivers"), glxinfo showed that it still being rendered by Mesa, the /sys/kernel/debug/vgaswitcheroo directory has gone missing, and the driver crashes with a traceback if I use xorg.conf to tell X to use fglrx. Anyone had any idea if it is possible to use this AMD card either with the radeon or the fglrx driver? logs: dmesg

  Read the article

• Booting Ubuntu on HP Pavilion g7 - 13.04 [duplicate]

  - by death2040

  This question already has an answer here: My computer boots to a black screen, what options do I have to fix it? 24 answers I have a HP Pavilion G7 with an AMD A4 processor and Radeon graphics. I want to install Ubuntu on my laptop but whenever I put the Ubuntu live CD in it and boot to it, the screen shows the Ubuntu logo and the four little dots then after about a minute or two the screen goes black. I can tell the screen is still on but it doesn't have anything on it. I'm beginning to wonder if its a driver problem but I can't really install the drivers when I cant even get Ubuntu to show anything except a loading screen. I've already tried using 12.04 and 12.10 and all the others down to Ubuntu 10. none of them worked. All the other versions don't even show the Ubuntu logo. I'd prefer to have Ubuntu 13.04 on it if its possible but I haven't had any luck finding a solution. I've also tried using WUBI installer in Windows 7 but all that did was make my computer slower for windows and it does the same with the screen when i boot it to Ubuntu. I'm trying to use Ubuntu alongside Windows 7. I cant find any solution on Google. It wont load anything and I know that there is a program called grub on Ubuntu that I used on my desktop computer when it had graphics trouble but the trouble with my desktop was minor things like the screen would flash and then show weird patterns on the screen. But I can't find anything on what to do with the HP laptop. Please help. I use this laptop a lot for games on Windows 7 and I just want to use Ubuntu for when I take my laptop to school and for school stuff. Edit: I just tried booting it in nomodeset and some other things and still didn't work. It did boot up but now when it goes to install alongside windows it crashes and says Ubuntu is forcing reboot or something like that Also, this question is different from the black screen at boot issue because when I do use nomodeset on my computer and select install Ubuntu it will go as far as the screen where you can choose to replace Windows or run alongside Windows. Then after I click continue it ejects the live CD and turns off my computer without installing anything. The error message it shows when it ejects the disk says signal 15, shutting down - modem manager [1675]: <info> Caught nm-dispatcher.action: Caught signal 15, shutting down... *Deconfiguring network interfaces... Please remove installation media and close the tray (if any) then press ENTER *Deactivating swap... *Stopping remaining crypto disks... *stopping early crypto disks... unmount: /run/lock: not mounted unmount: /run/shm: not mounted

  Read the article

• Investing in Servers by Intel

  - by Koushal Deshpande

  Originally posted on: http://geekswithblogs.net/BizTalkAndOtherTechs/archive/2013/10/31/investing-in-servers-by-intel.aspxA nice article reference from Intel, refer here. Referees to cloud as well. Choose correctly what you need. 1 Do determine right server for your company. There is no use getting a server that has redundant services but still add to the costs. 2 Do get servers that can be upgraded. A server with limited memory and storage may not be able to keep up with your business growth. The basic memory and storage options might not be sufficient. Consider at least 8GB of RAM and 1 terabyte of hard disk space. 3 Do check the server has at least one Gigabit Ethernet port. This allows high speed transferring of files and increases productivity for your employees. USB and Firewire ports may not be enough as their transfer speed is too low and will affect the productivity of your company. Infinite Technologies is ready to help perform this upgrade. Contact Infinite Technologies now View our other resellers » 4 Do verify that the server comes with documentation. Documentation allows you to make a claim when your server breaks down and is supported by a warranty. 6 Do check the support options for the server from the manufacturer. Different manufacturer has different support options such as maintenance plans and software upgrades. 5 Do always look into the warranty. Get an enhanced warranty that guarantees response and repair time to avoid disruption. 7 Do get server management tools that can be used on any computer. Server management tools should be cross compatible across different operating systems to take into account future PC replacements. 8 Do check the power usage of the servers. Get the right power supply to avoid damaging server hardware and consider the Intel® Xeon® E3 processor to help save on your electricity bills. 9 Do check what built-in security packages are available. Ensure that your server is protected. Built-in security1 helps you save on getting add on security packages.

  Read the article

• How to Make Objects Fall Faster in a Physics Simulation

  - by David Dimalanta

  I used the collision physics (i.e. Box2d, Physics Body Editor) and implemented onto the java code. I'm trying to make the fall speed higher according to the examples: It falls slower if light object (i.e. feather). It falls faster depending on the object (i.e. pebble, rock, car). I decided to double its falling speed for more excitement. I tried adding the mass but the speed of falling is constant instead of gaining more speed. check my code that something I put under input processor's touchUp() return method under same roof of the class that implements InputProcessor and Screen: @Override public boolean touchUp(int screenX, int screenY, int pointer, int button) { // TODO Touch Up Event if(is_Next_Fruit_Touched) { BodyEditorLoader Fruit_Loader = new BodyEditorLoader(Gdx.files.internal("Shape_Physics/Fruity Physics.json")); Fruit_BD.type = BodyType.DynamicBody; Fruit_BD.position.set(x, y); FixtureDef Fruit_FD = new FixtureDef(); // --> Allows you to make the object's physics. Fruit_FD.density = 1.0f; Fruit_FD.friction = 0.7f; Fruit_FD.restitution = 0.2f; MassData mass = new MassData(); mass.mass = 5f; Fruit_Body[n] = world.createBody(Fruit_BD); Fruit_Body[n].setActive(true); // --> Let your dragon fall. Fruit_Body[n].setMassData(mass); Fruit_Body[n].setGravityScale(1.0f); System.out.println("Eggs... " + n); Fruit_Loader.attachFixture(Fruit_Body[n], Body, Fruit_FD, Fruit_IMG.getWidth()); Fruit_Origin = Fruit_Loader.getOrigin(Body, Fruit_IMG.getWidth()).cpy(); is_Next_Fruit_Touched = false; up = y; Gdx.app.log("Initial Y-coordinate", "Y at " + up); //Once it's touched, the next fruit will set to drag. if(n < 50) { n++; }else{ System.exit(0); } } return true; } And take note, at show() method , the view size from the camera is at 720x1280: camera_1 = new OrthographicCamera(); camera_1.viewportHeight = 1280; camera_1.viewportWidth = 720; camera_1.position.set(camera_1.viewportWidth * 0.5f, camera_1.viewportHeight * 0.5f, 0f); camera_1.update(); I know it's a good idea to add weight to make the falling object falls faster once I released the finger from the touchUp() after I picked the object from the upper right of the screen but the speed remains either constant or slow. How can I solve this? Can you help?

  Read the article

• Cannot get 3D OpenGL support in Vmware guests, how can I fix this?

  - by jjapol

  I have been working at this problem for 2 days now. I cannot for the life of me enable 3D support in VMWare 9 guests. My specifications are: Hardware: Dell Latitude E5520 laptop. Processor: Intel i7-2620M CPU @ 2.70GHz × 4. Memory: 8GB. Video: Intel Sandybridge Mobile x86/MMX/SSE2 OS: Ubuntu 12.04.1 LTS, 32 bit. Vmware Workstation: 9.0.1 build-894247 Glxgears functions fine. Frame rate is ~60fps. Vmware guest: Windows 7 Starting the Windows 7 guest in VMware throws the following errors: No 3D support is available from the host. and Hardware graphics acceleration is not available. I've read through this VMware forum thread, but again the hardware in the post is different (nVidia). I've followed the instructions at this Ask Ubuntu post as closely as possible as the question is nearly the same as mine although my hardware is different. Answer 1 regarding setting mks.gl.allowBlacklistedDrivers = TRUE; in my vmx configuration file causes the VM to crash when it starts. The second answer I followed as closely as possible. I uninstalled VMware, Did sudo apt-get install build-essential linux-headers-$(uname -r) at a terminal, Added the PPA https://launchpad.net/~glasen/+archive/intel-driver, Then at a terminal did sudo apt-get update && sudo apt-get upgrade -y I reinstalled VMware and have the same results: no 3D in guests. I'm getting the feeling that something is awry with the Sandy Bridge driver, but I can't seem to come up with any solutions. Has anyone out there run across this problem also? By the way, the operation of the likes of Solidworks and AutoCad within a Windpws 7 guest does appear to be improved in VMware 9 vs VMware 8 in spite of the fact that 3D support is lacking in the Windows 7 guest. I'd also add that my glxinfo file was nearly identical to the glxinfo file posted at askubuntu.com/questions/181829/…. I had a total of seven minor differences per a comparison using Meld. –

  Read the article

• Impressions from VMworld - Clearing up Misconceptions

  - by Monica Kumar

  Gorgeous sunny weather…none of the usual summer fog…the Oracle Virtualization team has been busy at VMworld in San Francisco this week. From the time exhibits opened on Sunday, our booth staff was fully engaged with visitors. It was great to meet with customers and prospects, and there were many…most with promises to meet again in October at Oracle OpenWorld 2012. Interests and questions ran the gamut - from implementation details to consolidating applications to how does Oracle VM enable rapid application deployment to Oracle support and licensing. All good stuff! Some inquiries are poignant and really help us get at the customer pain points. Some are just based on misconceptions. We’d like to address a couple of common misconceptions that we heard: 1) Rapid deployment of enterprise applications is great but I don’t do this all the time. So why bother? While production applications don’t get updated or upgraded as often, development and QA staging environments are much more dynamic. Also, in today’s Cloud based computing environments, end users expect an entire solution, along with the virtual machine, to be provisioned instantly, on-demand, as and when they need to scale. Whether it’s adding a new feature to meet customer demands or updating applications to meet business/service compliance, these environments undergo change frequently. The ability to rapidly stand up an entire application stack with all the components such as database tier, mid-tier, OS, and applications tightly integrated, can offer significant value. Hand patching, installation of the OS, application and configurations to ensure the entire stack works well together can take days and weeks. Oracle VM Templates provide a much faster path to standing up a development, QA or production stack in a matter of hours or minutes. I see lots of eyes light up as we get to this point of the conversation. 2) Oracle Software licensing on VMware vSphere In the world of multi-vendor IT stacks, understanding license boundaries and terms and conditions for each product in the stack can be challenging.  Oracle’s licensing, though, is straightforward.  Oracle software is licensed per physical processor in the server or cluster where the Oracle software is installed and/or running.  The use of third party virtualization technologies such as VMware is not allowed as a means to change the way Oracle software is licensed.  Exceptions are spelled out in the licensing document labeled “Hard Partitioning". Here are some fun pictures! Visitors to our booth told us they loved the Oracle SUV courtesy shuttles that are helping attendees get to/from hotels. Also spotted were several taxicabs sporting an Oracle banner! Stay tuned for more highlights across desktop and server virtualization as we wrap up our participation at VMworld.

  Read the article

• Live CD has black screen HP DV6

  - by Shaun Killingbeck

  Attempting to install/try ubuntu (11.10, 12.04) on my new laptop, using a liveCD (and tried USB). I get the purple screen (with the man/keyboard at the bottom) and after that the screen flashes bright white before going black. Ubuntu continues to load in the background, with login sound etc but the screen is off. I have tried as many different solutions as I could find including: using nomodestep, xforcevesa, i915.modeset=0, and also now i915.modeset=1 in boot options (seperately): varying consequences, but either I end up at a blinking cursor with no prompt, a command line (startx fails: no screen found), or the original blank screen again Tried booting from VirtualBox - it crashes at the same place the screen would go blank when using a CD/USB tried 11.04: I don't have this problem BUT when trying to install, I get a ubi-partman error 141 (possibly down to the three partitions that came on my laptop... not sure why HP needed there own separate partition for HP Tools...) Model: HP Pavillion DV6 6B08SA Processor: AMD Quad-Core A6-3410MX APU with Radeon HD 6545G2 Dual Graphics (1.6 GHZ 4 MB L2 cache ) Chipset: AMD RS880M Any help would be greatly appreciated. I just want to be able to partition the drive and install Ubuntu. I'm assuming the issue is graphics card related, although I have no confirmation of that. Update: Tried the ?orkarounds on https://wiki.ubuntu.com/X/Troubleshooting/BlankScreen - set gfxpayload=text changed nothing, removing splash did nothing and setting vesafb.nonsense=1 did nothing either. I'd like to be able to collect some log information somehow, but I can't get to a command line from the liveCD. tried using the latest 12.04 beta, same issue tried nomodeset without splash or quiet. get the following (tail of) output before it freezes on that screen: * Starting configure network device security [OK] * Starting configure network device [OK] [ 25.720899] ieee80211 phy0: w1_ops_config: change monitor mode: false (implement) [ 25.720923] ieee80211 phy0: w1_ops_config: change power-save mode: false (implement) * Starting restore sound card(s') mixer state(s) [fail] [ 25.721849] ieee80211 phy0: w1_ops_bss_info_changed: qos enabled: false (implement) * Stopping save kernel messages [OK] * Starting bluetooth [OK] * PulseAudio configured for per-user sessions saned disabled; edit /etc/default/saned [ 25.988016] hci_cmd_timer: hci0 command tx timeout [ 26.207225] bad LUN (0:1) [ 26.223735] bad target number (1:0) [ 26.252111] bad target number (2:0) [ 26.272170] bad target number (3:0) [ 26.300154] bad target number (4:0) [ 26.328162] bad target number (5:0) [ 26.344180] bad target number (6:0) [ 26.368142] bad target number (7:0) * Checking battery state... [OK] * Stopping System V runlevel capability [OK] Does this give any indication of the problem? the false (implement) messages also reappear when I press the power button to ask it to shutdown, followed by a [fail] status for killing remaining processes.

  Read the article

• Interconnect nodes in a Java distributed infrastructure for tweet processing

  - by David Moreno García

  I'm working in a new version of an old project that I used to download and process user statuses from Twitter. The main problem of that project was its infrastructure. I used multiple instances of a java application (trackers) to download from Twitter given an specific task (basically terms to search for), connected with a central node (a web application) that had to process all tweets once per day and generate a new task for each trackers once each 15 minutes. The central node also had to monitor all trackers and enable/disable them under user petition. This, as I said, was too slow because I had multiple bottlenecks, so in this new version I want to improve the infrastructure and isolate all functionalities in specific nodes. I also need a good notification system to receive notifications for any node. So, in the next diagram I show the components that I'll need in this new version: As you can see, there are more nodes. Here are some notes about them: Dashboard: Controls trackers statuses and send a single task to each of them (under user request). The trackers will use this task until replaced with a new one (if done, not each 15 minutes like before). Search engine: I need to store all the tweets. They are firstly stored in a local database for each tracker but after that I'm thinking on using something like Elasticsearch to be able to do fast searches. Tweet processor: Just and isolated component with its own database (maybe something like the search engine to have fast access to info generated by the module). In the future more could be added. Application UI: A web application with a shared database with the Dashboard (mainly to store users information and preferences). Indeed, both could be merged into a single web. The main difference with the previous version of the project is that now they will be isolated and they will only show information and send requests. I will not do any heavy task in them (like process tweets as I did before). So, having this components, my main headache is how to structure all to not have to rewrite a lot of code every time I need to access any new data. Another headache is how can I interconnect nodes. I could use sockets but that is a pain in the ass. Maybe a REST layer? And finally, if all the nodes are isolated, how could I generate notifications for each user which info is only in the database used by the Application UI? I'm programming this using Java and Spring (at least I used them in the last version) but I have no problems with changing the language if I can take advantage of a tool/library/engine to make my life easier and have a better platform. Any comment will be appreciated.

  Read the article

• Cloud Computing: Start with the problem

  - by BuckWoody

  At one point in my life I would build my own computing system for home use. I wanted a particular video card, a certain set of drives, and a lot of memory. Not only could I not find those things in a vendor’s pre-built computer, but those were more expensive – by a lot. As time moved on and the computing industry matured, I actually find that I can buy a vendor’s system as cheaply – and in some cases far more cheaply – than I can build it myself.   This paradigm holds true for almost any product, even clothing and furniture. And it’s also held true for software… Mostly. If you need an office productivity package, you simply buy one or use open-sourced software for that. There’s really no need to write your own Word Processor – it’s kind of been done a thousand times over. Even if you need a full system for customer relationship management or other needs, you simply buy one. But there is no “cloud solution in a box”.  Sure, if you’re after “Software as a Service” – type solutions, like being able to process video (Windows Azure Media Services) or running a Pig or Hive job in Hadoop (Hadoop on Windows Azure) you can simply use one of those, or if you just want to deploy a Virtual Machine (Windows Azure Virtual Machines) you can get that, but if you’re looking for a solution to a problem your organization has, you may need to mix Software, Infrastructure, and perhaps even Platforms (such as Windows Azure Computing) to solve the issue. It’s all about starting from the problem-end first. We’ve become so accustomed to looking for a box of software that will solve the problem, that we often start with the solution and try to fit it to the problem, rather than the other way around.  When I talk with my fellow architects at other companies, one of the hardest things to get them to do is to ignore the technology for a moment and describe what the issues are. It’s interesting to monitor the conversation and watch how many times we deviate from the problem into the solution. So, in your work today, try a little experiment: watch how many times you go after a problem by starting with the solution. Tomorrow, make a conscious effort to reverse that. You might be surprised at the results.

  Read the article

• MS in Computer Science after BE in electronics

  - by Abhinav

  I am doing my 3rd year Bachelors in Electronics and Electrical Communication but from the first year I have been interested in Computer Science. But at that time it was just my hobby. But in second year when I joined robotics my love for computer science rose. I with my team came in top three in 2 National Competition (Technical fests of different IITs) where we used Image Processing, Hardware interfacing etc. But then I realised that Computer Science is not just about coding. I took many lectures from online free schools like Udacity, Coursera in subjects related to Artificial Intelligence, Building a Search Engine, Design and Analysis of Algorithm, Programming a Robotic Car, Programming Languages, Machine Learning, Software Engineering as a Service, WebApps Engineering, Compilers, Applied Crypotography etc. I also did some courses in Core and Advanced Java in my second year from training institute. I will also be taking course in Statistics, Databases, Discrete Mathematics from 25th June. Now I realized how vast is the field of Computer Science and how efficient you become on deciding algorithms and classifying problems into different subfields which have been thoroughly researched so you don't always do brute force thing or naive programming. Now this field has become kind of passion for me. Adding to the fact I am also doing my 6 months internship in software field in Texas Instruments where I am working on Automation and Algorithms. I also have some 5-6 good college level projects in Softwares and Robotics. I also like Electronics but only some fields like Operating System(this subject was there in Electronics also), Micro Processor, Digital, Computer Architecture, DSPs etc. I really want to pursue MS in some field of Computer Science. I am giving GRE in October/November. Till now I have good CG of around 9.4/10 and my 1 year in college is still left. Do I have any chance that some good University in US will consider me for MS in field related to computer science or Robotics. Also Can you suggest somethings that I can do during this 1 year to increase my chances for MS or should I apply for EECS(Electrical Engineering and Computer Science) and then I can shift more towards Computer Science as my major option. My main aim is to do Phd after Ms in CS if I am able to do that somehow. I know that I have to put much extra effort to understand things in MS than CS undergraduates but I will do that with my full dedication, also when I communicate with my college CS students or during my internship period I didn't feel that I am missing very much stuff that they know and was very comfortable during my internship with software employees.

  Read the article

• Need help identifing what resources (eg. In MIT OpenCourseWare) can help me prepare for a test [closed]

  - by jiewmeng

  I am entering uni soon. I can sit for a placement test to see if I elegible for exemptions. The details are http://www.comp.nus.edu.sg/undergraduates/TestScope11_12.html Or CS2100 Computer Organisation (please click title) The objective of this module is to familiarise students with the fundamentals of computing devices. Through this module students will understand the basics of data representation, and how the various parts of a computer work, separately and with each other. This allows students to understand the issues in computing devices, and how these issues affect the implementation of solutions. Topics covered include data representation systems, combinational and sequential circuit design techniques, assembly language, processor execution cycles, pipelining, memory hierarchy and input/output systems. Recommended Textbooks Digital Design: Principles and Practices [DDPP] by John F. Wakerly, Prentice-Hall. ISBN 0-13-324500-4. Computer Organizations and Design (The hardware/software interface) by David A. Patterson and John L. Hennessy. CS2105 Introduction to Computer Networks (please click title) This course aims to provide a broad introduction to computer networks and some appreciations of network application programming. It covers a range of topics including basic data communication and computer network concepts, protocols, networked computing concepts and principles, network applications development and network security. The emphasis of teaching is on the working principles and application of computer networks. As an integral part of the course, tutorials and practical assignments enforcing learning will also be given. These assignments provide an early exposure in network application programming and they should be able to complete by using personal computers and school's network facilities. Topics included: An overview of computer networks and the Internet Basic data communications Application layer Transport layer Network layer and routing Link layer and local area networks Recommended Textbook James F. Kurose & Keith W. Ross, Computer networking: A top-down approach featuring internet, Addison Wesley, 2001 I am wondering what resources eg. MIT OpenCourseWare or other universities resources are available to help he perpare for these particular modubles. I am thinking does the Networking one look like CCNA? The computer oragization. Its like electronics, assembly etc? I learnt some electronics in Poly but looking at the sample papers, uni looks very different... I have about 1 month to prepare if I want any chance of exempting from these modules :) any help?

  Read the article

• Compiling for T4

  - by Darryl Gove

  I've recently had quite a few queries about compiling for T4 based systems. So it's probably a good time to review what I consider to be the best practices. Always use the latest compiler. Being in the compiler team, this is bound to be something I'd recommend But the serious points are that (a) Every release the tools get better and better, so you are going to be much more effective using the latest release (b) Every release we improve the generated code, so you will see things get better (c) Old releases cannot know about new hardware. Always use optimisation. You should use at least -O to get some amount of optimisation. -xO4 is typically even better as this will add within-file inlining. Always generate debug information, using -g. This allows the tools to attribute information to lines of source. This is particularly important when profiling an application. The default target of -xtarget=generic is often sufficient. This setting is designed to produce a binary that runs well across all supported platforms. If the binary is going to be deployed on only a subset of architectures, then it is possible to produce a binary that only uses the instructions supported on these architectures, which may lead to some performance gains. I've previously discussed which chips support which architectures, and I'd recommend that you take a look at the chart that goes with the discussion. Crossfile optimisation (-xipo) can be very useful - particularly when the hot source code is distributed across multiple source files. If you're allowed to have something as geeky as favourite compiler optimisations, then this is mine! Profile feedback (-xprofile=[collect: | use:]) will help the compiler make the best code layout decisions, and is particularly effective with crossfile optimisations. But what makes this optimisation really useful is that codes that are dominated by branch instructions don't typically improve much with "traditional" compiler optimisation, but often do respond well to being built with profile feedback. The macro flag -fast aims to provide a one-stop "give me a fast application" flag. This usually gives a best performing binary, but with a few caveats. It assumes the build platform is also the deployment platform, it enables floating point optimisations, and it makes some relatively weak assumptions about pointer aliasing. It's worth investigating. SPARC64 processor, T3, and T4 implement floating point multiply accumulate instructions. These can substantially improve floating point performance. To generate them the compiler needs the flag -fma=fused and also needs an architecture that supports the instruction (at least -xarch=sparcfmaf). The most critical advise is that anyone doing performance work should profile their application. I cannot overstate how important it is to look at where the time is going in order to determine what can be done to improve it. I also presented at Oracle OpenWorld on this topic, so it might be helpful to review those slides.

  Read the article

• How to troubleshoot ethernet port on laptop

  - by Psallas Vassilios

  I have a problem with my wired connection. To be more specific, my laptop doesn't seems to recognize that I have plugged in an ethernet cable. I tried to download new drivers for my ethernet card, but I couldn't find any solutions. Maybe because I am new to Linux, so I'm not familiar with running commands in the terminal. OK I have typed the command and here are the results: 00:04.0 Ethernet controller [0200]: Silicon Integrated Systems [SiS] 191 Gigabit Ethernet Adapter [1039:0191] (rev 02) For the second reply I don't know if the following is what you asked me: ?Memory: 3.9 GiB ?Processor: Intel Core 2 Duo CPU P8800 @ 2.66GHz × 2 ?OS type: 32-bit My Ethernet connection had some problem on Windows too. I have changed recently my internet provider, and since then my ethernet cable is not recognized by the laptop. At that time I was still on Windows. I thought that with Ubuntu the problem would be solved, but unfortunately the problem still persists. If someone can help me to solve my problem I'll be thankful. Here are the results of the three first commands you told me to run: lsmod | grep sis190 sis190 22570 0 sudo modprobe sis190 ifconfig eth0 Link encap:Ethernet HWaddr 00:90:f5:90:81:7e UP BROADCAST MULTICAST MTU:1500 Metric:1 RX packets:0 errors:0 dropped:0 overruns:0 frame:0 TX packets:0 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:0 (0.0 B) TX bytes:0 (0.0 B) lo Link encap:Local Loopback inet addr:127.0.0.1 Mask:255.0.0.0 inet6 addr: ::1/128 Scope:Host UP LOOPBACK RUNNING MTU:16436 Metric:1 RX packets:185 errors:0 dropped:0 overruns:0 frame:0 TX packets:185 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:0 RX bytes:22672 (22.6 KB) TX bytes:22672 (22.6 KB) wlan0 Link encap:Ethernet HWaddr 00:25:d3:2c:3a:ae inet addr:192.168.1.72 Bcast:192.168.1.255 Mask:255.255.255.0 inet6 addr: fe80::225:d3ff:fe2c:3aae/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:260 errors:0 dropped:0 overruns:0 frame:0 TX packets:363 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:71992 (71.9 KB) TX bytes:52000 (52.0 KB) and the results of running the last two commands: dmesg | grep -e eth -e sis190 [ 0.816667] sis190: sis190 Gigabit Ethernet driver 1.4 loaded [ 0.816728] sis190 0000:00:04.0: setting latency timer to 64 [ 0.816751] sis190: 0000:00:04.0: Read MAC address from EEPROM [ 0.904032] sis190: 0000:00:04.0: Realtek PHY RTL8201 transceiver at address [ 1.416030] sis190: 0000:00:04.0: Using transceiver at address 1 as default [ 1.448235] sis190 0000:00:04.0: eth0: 0000:00:04.0: SiS 191 PCI Gigabit Ethernet adapter at f8410000 (IRQ: 19), 00:90:f5:90:81:7e [ 1.448238] sis190 0000:00:04.0: eth0: GMII mode. [ 1.448243] sis190 0000:00:04.0: eth0: Enabling Auto-negotiation [ 11.560907] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 16.372019] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 16.372265] IPv6: ADDRCONF(NETDEV_UP): eth0: link is not ready [ 26.424038] sis190 0000:00:04.0: eth0: auto-negotiating... nm-tool NetworkManager Tool State: connected (global) - Device: eth0 ----------------------------------------------------------------- Type: Wired Driver: sis190 State: unavailable Default: no HW Address: 00:90:F5:90:81:7E Capabilities: Carrier Detect: yes Wired Properties Carrier: off

  Read the article

• How do I maintain a really poorly written code base?

  - by onlineapplab.com

  Recently I got hired to work on existing web application because of NDA I'm not at liberty to disclose any details but this application is working online in sort of a beta testing stage before official launch. We have a few hundred users right now but this number is supposed to significantly increase after official launch. The application is written in PHP (but it is irrelevant to my question) and is running on a dual xeon processor standalone server with severe performance problems. I have seen a lot of bad PHP code but this really sets new standards, especially knowing how much time and money was invested in developing it. it is as badly coded as possible there is PHP, HTML, SQL mixed together and code is repeated whenever it is necessary (especially SQL queries). there are not any functions used, not mentioning any OOP there are four versions of the app (desktop, iPhone, Android + other mobile) each version has pretty much the same functionality but was created by copying the whole code base, so now there are some differences between each version and it is really hard to maintain the database is really badly designed, which is causing severe performance problems also for fixing some errors in PHP code there is a lot of database triggers used which are updating data on SELECT and on INSERT so any testing is a nightmare Basically, any sin of a bad programming you can imagine is there for example it is not only possible to use SQL injections in literally every place but you can log into app if you use a login which doesn't exist and an empty password. The team which created this app is not working on it any more and there is an outsourced team which suggested that there are some problems but was never willing to deal with the elephant in the room partially because they've got a very comfortable contract and partially due to lack of skills (just my opinion). My job was supposed to be fixing some performance problems and extending existing functionality but first thing I was asked to do was a review of the existing code base. I've made my review and it was quite a shock for the management but my conclusions were after some time finally confirmed by other programmers. Management made it clear that it is not possible to start rewriting this app from scratch (which in my opinion should be done). We have to maintain its operable state and at the same time fix performance errors and extend the functionality. My question is, as I don't want just to patch the existing code, how to transform this into properly written app while keeping the existing code working at the same time? My plan is: Unify four existing versions into common code base (fixing only most obvious errors). Redesign db and use triggers to populate it with data (so data will be maintained in two formats at the same time) All new functionality will be written as separate project. Step by step transfer existing functionality into the new project After some time everything will be in the new project Some explanation about #2, right now it is practically impossible to make any updates in existing db any change requires reviewing whole code and making changes in many places. Is such plan feasible at all? Another solution is to walk away and leave the headache to someone else.

  Read the article

• Setting up Ubuntu on my mother's computer

  - by idealmachine

  Intended use My mother had an old Compaq desktop computer running Windows 98, which she used for occasional Web browsing and playing cards. The name of her card game is Hoyle Card Games 3. Although I had to repair it several times over the last 10 years, it worked fine until it finally died at the end of last year. Hardware specifications A relative brought up a newer computer soon afterward: Operating system: Windows XP Asus K8N motherboard (with broken on-board sound; getting a sound card) Athlon 64? processor (don't remember the clock speed) 512 MB RAM Hope the graphics card works... Replacement sound card will be one of: Ensoniq ES1370 AudioPCI Diamond Monster Sound MX300 (Aureal chipset) Sound Blaster Audigy 2 SE Peripherals HP Scanjet 3400c scanner (USB connected) HP LaserJet multi-function printer (parallel port connected, and printing works with a PCL driver) Same serial mouse as old computer Question I had set up an SSH/VNC connection to allow for remotely working out problems. Or so I thought. A month later, the computer would not boot, rendering the SSH connection useless and an OS reinstall necessary. Unfortunately, I have neither the original Windows disc nor the product key. Unless I were to pay $200 for a full Windows 7 Home Premium license for my computer, I would not be able to re-install Windows XP on hers. I consider myself an advanced Linux user, having used Debian for years. So here are my questions. I have only one day to decide whether to use Ubuntu or buy Windows: A quick search leads me to believe all the hardware listed above is supposed to work with Linux, but am I mistaken? Would Ubuntu/Xubuntu suffice (specify which one if it matters), or would I be better off paying the $200 necessary for Windows XP? Is the card game likely to run on Wine? I believe the minimum system requirement is Windows 95. Failing Wine compatibility, will VirtualBox run fast enough on such a computer (Windows 98 as the guest OS)? Are there any free card games just as good? She plays mainly Bridge, Poker, and Solitaire. Is there any "Large Fonts" option for those with poor vision? The lack of it would be a big disadvantage. BONUS: Although I would probably replace the old mouse upon a move to Ubuntu, is it even possible to get a serial mouse working?

  Read the article

• Understanding the SQL Server 2008 R2 Installation Center

  - by Enrique Lima

  What is available to us through those links?  Have you taken the time to explore and identify what could be useful to you? One of many gems that has come to my attention is the possibility of provisioning SQL Server to work in an image based environment (hint: Virtualization Template perhaps?!?).   Planning: Includes requirements information, documentation, how to guides, online documentation installation and other tools. Among the other tools you will find the System Configuration checker and The Upgrade Advisor. Both tools very important to ensure your deployment and installation would be successful.     Installation:  This sections focuses on getting installations going, from standalone to cluster when it comes to new instances.  Add new nodes to an existing cluster, and also perform upgrades (in this case to SQL Server 2008 R2).  Also part of this is the option to find updates available.   Maintenance: We find in this section, options that will assist us in tasks like repairing corrupt installations to removing nodes from a cluster. An option that is interesting (and we should discuss benefits later in another post) is to be able to do an Edition Upgrade, this is a feature expansion and addition based on your product installation (Developer to Enterprise, for example)   Tools:  From the System Configuration Checker to identify readiness for deployment in a successful manner, to being able to report on features installed.  And being able to run upgrades of existing packages developed in the 2005 offering to the 2008 R2 release for SSIS.   Resources: Useful and essential links to gather information and guidance.   Advanced: Here is where it gets interesting.  I break this down into 3 main groups: Installation Automation: When you install SQL Server there is a configuration file that gets dropped (ConfigurationFile.ini) that would allow for you to perform automated installations.  There are switches and options that go with this to have that process working. Cluster configuration for Sysprep: Create images that are cluster ready, 2 options, start the prep work, and then the complete once at the final destination. Stand-alone configuration for Sysprep:  Like the clustering counterpart, 2 options, prep and complete.  Giving you the option to create standard templates for your SQL Server deployments. I find it fitting that the 3 topics listed here should (and will) be additional topics I will discuss.   Options: Very clear and specific about what this means. Select the Processor Type or the Installation Media Root Path.

  Read the article

< Previous Page | 81 82 83 84 85 86 87 88 89 90 91 92  | Next Page >