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• LinkShare - A Customer Case of Highly Scalable BI and Analytics for E-Commerce Marketing

  LinkShare is one of the largest users of BI and Analytics for its innovative, E-commerce, Affiliate Marketing and Pay-per-Action services. It use OBIEE to gain insights into its own performance but also offers vast amounts of data and analytics to its customers on the performance of their marketing programs and campaigns. This session will highlight how creative firms can use BI to transform the products and services they provide to their customers and use BI as a competitive differentiator.

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• Creating Indicator and Gauge Report in SSRS - SQL Server 2008 R2

  SQL Server Reporting Services allows you to embed indicators and Gauges in your report to analyze the data and its state. Indicators are minimal gauges that convey the state of a single data value at a glance and are mostly used to represent state value of Key Performance Indicator (KPI). New! SQL Monitor 3.0 Red Gate's multi-server performance monitoring and alerting tool gets results from Day One.Simple to install and easy to use – download a free trial today.

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• Cursor-Killing: Retrieving Recently Modified Data

  Cursors are considered by many to be the bane of good T-SQL. What are the best ways to avoid iterative T-SQL and to write queries that look and perform beautifully? In the next part of an ongoing series, we look at ways to efficiently retrieve recently modified data. FREE eBook – "45 Database Performance Tips for Developers"Improve your database performance with 45 tips from SQL Server MVPs and industry experts. Get the eBook here.

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• Event-Driven Debugging

  - by Brian Donahue

  Most application troubleshooting involves getting an error, analyzing the error message, and at worst, attaching a debugger to work out the real cause. What is not really covered is how to troubleshoot an applicaiton that is not errant, but is having a performance issue, and more than likely, in the middle of the night when you are snug in your bed, sawing logs. What you need is an ever-vigilant cyborg who never sleeps to sit in front of your server all night, but as SkyNet is not live yet, you can settle for the next-best thing. Windows provides performance counters and alerts that can tell you when an applicaiton reaches an unacceptable threshold of naughty behavior, but although it can tattle on your brainchild, it won't be the child psychiatrist that you need to tell you why he's pulling your server's pigtails and pulling faces at the teacher. What you need is to plug a debugger into performance monitor and have it tell you what's going on with your applicaiton at the time. For this purpose, I'd used Microsoft's MDbgEngine as the basis for an applicaiton that will dump a program's stacks, I call it Application Slicer Dicer Wonder Dumper Super Cyborg, or StackOMatic for short. StackOMatic can look at a program's behavior and tell you if the stacks are not moving, but it can also work on the command-line to dump all managed methods on the stack at will. Now that there is a command you can use to dump the stacks, all you need to do is politely tell Windows to run it when you're displeased with your creation as it's trashing the CPU of your server at 3 AM. The first step is to create a scheduled task to tell StackOMatic to dump your applicaiton. Start Task Scheduler and right-click Task Scheduler Library and then Create Task. For this exercise I'm creating a task that will dump the Red Gate SQL Monitor Base Monitor Service. In the Actions tab, I enter the path to StackOMatic and use the arguments to log the stack dump to a file: /PN:RedGate.Response.Engine.Alerting.Base.Service /OUT:c:\users\administrator\MonitorLog.txt Next, I go into Windows Server 2008's Reliability and Performance Monitor and add a new Data Collector Set. This set will produce an alert on the %Processor Time for the service. When the processor time breaches 50%, it will run the StackDumpBaseService task I created. Whenever the service misbehaves, it will append to the log file. Now when I go to work in the morning, I can see what the service was doing when it overloaded the processor and take action.

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• Normal Redundancy (Double Mirroring) Option Available

  - by TammyBednar

  Normal 0 false false false EN-US X-NONE X-NONE MicrosoftInternetExplorer4 /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-qformat:yes; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin:0in; mso-para-margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:10.0pt; font-family:"Calibri","sans-serif";} The Oracle Database Appliance 2.4 Patch was released last week and provides you an option of ASM normal redundancy (double mirroring) during the initial deployment of the Database Appliance. The default deployment of the Oracle Database Appliance is high redundancy for the +DATA and +RECO disk groups. While there is 12TB of raw shared storage available, the Database Backup Location and Disk Group Redundancy govern how much usable storage is presented after the initial deployment is completed. The Database Backup Location options are Local or External. When the Local Backup Option is selected, this means that 60% of the available shared storage will be allocated for the Fast Recovery Area that contains database backups and archive logs. The External Backup Option will allocate 20% of the available shared storage to the Fast Recovery Area. So, let’s look at an example of High Redundancy and External Backups. Disk Group Redundancy – High --> Triple Mirroring to provide ~4TB of available storage Database Backup Location – External --> 20% of available shared storage allocated to +RECO +DATA = 3.2TB of usable storage, +RECO = 0.8TB of usable storage What about Normal Redundancy with External Backups? Disk Group Redundancy – Normal --> Double Mirroring to provide ~6TB of available storage Database Backup Location – External --> 20% of available shared storage allocated to +RECO +DATA = 4.8TB of usable storage, +RECO = 1.2TB of usable storage As a best practice, we would recommend using Normal Redundancy for your test and/or development Oracle Database Appliances and High Redundancy for production.

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• Maximizing Throughput with TVPs

  TVPs offer several performance optimization possibilities that other bulk operations do not allow, and these operations may allow for TVP performance to exceed other bulk operations by an order of magnitude, especially for a pattern where subsets of the data are frequently updated. Want to work faster with SQL Server?If you want to work faster try out the SQL Toolbelt. "The SQL Toolbelt provides tools that database developers as well as DBAs should not live without." William Van Orden. Download the SQL Toolbelt here.

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• The SQL of Membership: Equivalence Classes & Cliques

  It is awkward to do 'Graph databases' in SQL to explore the sort of relationships and memberships in social networks because equivalence relations are classes (a set of sets) rather than sets. However one can explore graphs in SQL if the relationship has all three of the mathematical properties needed for an equivalence relationship. FREE eBook – "45 Database Performance Tips for Developers"Improve your database performance with 45 tips from SQL Server MVPs and industry experts. Get the eBook here.

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• Multiuser's impact on Access Database

  - by SilentRage47

  Can someone explain to me how are effected the performances of an Access 2003 DB when it's used by a lot (30) of users on the same LAN? I'm working on a vb6 project with this access 2003 DB wich performs ok on my local PC, but it's terrible when used across 20-30 users. It's there something I can do to improve performance? How can I understand what's the cause of this degradation in performance?

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• How to write a real time data acquisition program [closed]

  - by Tosin Awe

  I have to write a program in assembly language that will monitor temperature continuously, and I have no idea where to begin. The temperature must be displayed in BCD format, and the high and low set points will be programmed into the system. if the set points are exceeded then an alarm will be indicated. The low point is 20 degrees Celsius, and the high point is 24 degrees Celsius. Can somebody give me some hints on how to complete this task?

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• How Can a Website Benefit From Search Engine Optimization

  Search Engine Optimization, also plainly referred to as SEO is tuning the potentials of a website with the aim of getting high rankings in search engines like Google, Yahoo and Bing. Businesses battle for this high ranking because when web users search for particular services or products online, they only use specific keywords in the search engines then perform a web search.

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• Are there any limitations to using WinRT instead of .Net?

  - by jerrykobes

  From my understanding creating an application that runs on multiple architectures requires virtualization, and virtualization reduces performance since it creates a layer of abstraction. With Windows 8 supporting both Intel and ARM architectures should we expect slower performance with a WinRT app versus a .Net app running on an Intel device? Also, will WinRT support database connectivity and active directory access?

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• Measuring Site Responsiveness With Web 2.0 Technologies

  No longer will measurements of single pages provide a view into the end-to-end performance of the user online. Web operations teams need tools that will alert them in real time when their Web site performance falls below acceptable thresholds.

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• Buy Backlinks Which Are Relevant!

  The internet is complicated so, for SEO purposes, I like to think of it like a high school. In order to be the most popular kid (get high on Google SERPs), you need to have friends.

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• Exadata X3 launch webcast - Available on-demand

  - by Javier Puerta

  Available on-demand, this webcast covers everything partners need to know about Oracle’s next-generation database machine. You will learn how to improve performance by storing multiple databases in memory, lower power and cooling costs by 30%, and easily deploy a cloud based database service. Exadata X3 combines massive memory and low-cost disks to deliver the highest performance at the lowest cost. View here!

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• Make Money Online - Why You Cannot Ignore SEO

  Any entrepreneur with designs to make money online consistently should focus heavily on obtaining high rankings in the search engines. If it turns out that you are struggling to obtain high rankings for targeted search terms, it is time to determine if your website is giving the right message to the search engines. Quite frequently internet marketers are told of the importance of building one way links to their website, but are not made privy to the importance of the optimization of their actual website, otherwise known as on-page optimization.

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• Best SEO Methods For Organic Traffic

  Search engine optimization is a complex and ever changing science on the internet. While certain things never seem to change about ranking high in the search engines, others simply never stop changing. These days, there are really only a handful of reliable methods for ranking high in the search engines, and it is something that you will see website designers and internet marketers raving about.

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• Migration Guide: Migrating to SQL Server 2012 Failover Clustering and Availability Groups from Prior Clustering and Mirroring Deployments

  This paper provides guidance for customers who prior to SQL Server 2012 have deployed SQL Failover Clustering for local high availability and database mirroring for disaster recovery, and who want to migrate to SQL Server AlwaysOn. It describes the corresponding SQL Server AlwaysOn scenario and the migration paths to SQL Server AlwaysOn. It also contains the important knowledge and considerations that you must know in order to successfully migrate to a HADR solution based on SQL Server AlwaysOn technology, which implements AlwaysOn Failover Cluster Instances for high availability and AlwaysOn Availability Groups for disaster recovery.

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• Is Arch Linux Really Faster Than Ubuntu?

  <b>Phoronix:</b> "to test the performance claims of Arch versus others, we have compared the performance of the newest Arch 2010.05 media against Ubuntu Linux."

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• How to check if a variable is an integer? [closed]

  - by FyrePlanet

  I'm going through my C++ book and have currently made a working Guess The Number game. The game generates a random number based on current time, has the user input their guess, and then tells them whether it was too high, too low, or the correct number. The game functions fine if you enter a number, but returns 'Too High' if you enter something that is not a number (such as a letter or punctuation). Not only does it return 'too high', but it also continually returns it. I was wondering what I could do to check if the guess, as input by the user, is an integer and if it is not, to return 'Not a number. Guess again.' Here is the code. #include <iostream> #include <cstdlib> #include <ctime> using namespace std; int main() { srand(time(0)); // seed the random number generator int theNumber = rand() % 100 + 1; // random number between 1 and 100 int tries = 0, guess; cout << "\tWelcome to Guess My Number!\n\n"; do { cout << "Enter a guess: "; cin >> guess; ++tries; if (guess > theNumber) cout << "Too high!\n\n"; if (guess < theNumber) cout << "Too low!\n\n"; } while (guess != theNumber); cout << "\nThat's it! You got it in " << tries << " guesses!\n"; cout << "\nPress Enter to exit.\n"; cin.ignore(cin.rdbuf()->in_avail() + 1); return 0; }

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• Top 7 Ways to Get Traffic For Free

  Website without high site traffic is useless. Site traffic is truly important for website with high end design is not good if not followed by several visitors and frequent viewers. If you don't get large volume of traffic, don't worry for here are the top 7 ways on how to get site traffic for free.

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• Getting the Most out of Statistics

  Statistics keep track of our data and will tell SQL Server how to make the best optimization decisions. Knowing how they work can make understanding query and performance problems much easier! Free eBook - Performance Tuning with DMVsThis free eBook provides you with the core techniques and scripts to monitor your query execution, index usage, session and transaction activity, disk IO, and more. Download the free eBook.

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• DirectX works for 64-bit but not 32-bit

  - by dtbarne

  I'm trying to play a game (Civilization 5) which was previously working but no longer. I believe I've narrowed it down to a DirectX issue because I get an error running dxdiag.exe in 32 bit mode. My goal (at least I believe) is to get Direct3D Acceleration "Enabled" in dxdiag (as it is in 64 bit dxdiag). A very similar issue is here: http://answers.microsoft.com/en-us/windows/forum/windows_7-gaming/direct3d-acceleration-is-not-available-in-windows/4c345e6e-dc68-e011-8dfc-68b599b31bf5?page=1 The proposed answer, which looks very promising, doesn't seem to work for me. Like other users in that thread, HKEY_LOCAL_MACHINE\SOFTWARE\Wow6432Node\Microsoft\Direct3D\Drivers does not have a SoftwareOnly key to change. I even tried manually adding it as a string and dword, to no avail. I have a NVIDIA GeForce GT 525M, and before you ask, yes I've tried updating (also uninstalling, reinstalling) my drivers. I've also tried doing the same with DirectX (and Civilization 5 for that matter). Been debugging for some 4+ hours now after a full day of work and I've run out of ideas. I'm hoping somebody knows the solution here! :) Here's what I see when I open dxdiag: DxDiag has detected that there mgiht have been a problem accessing Direct3D the last time this program was used. Would you like to bypass Direct3D this time? No - Crash Yes - Works, but in Display tab: DirectDraw Acceleration: Disabled Direct3D Acceleration: Not Available AGP Texture Acceleration: Not Available If I click "Run 64-bit DxDiag", all three are "Enabled". I should also note that I've tried the following steps as Microsoft suggests, but I'm not able to do so as the "Change Settings" button is disabled. Some programs run very slowly—or not at all—unless Microsoft DirectDraw or Direct3D hardware acceleration is turned on. To determine this, click the Display tab, and then under DirectX Features, check to see whether DirectDraw, Direct3D, and AGP Texture Acceleration appear as Enabled. If not, try turning on hardware acceleration. Click to open Screen Resolution. Click Advanced settings. Click the Troubleshoot tab, and then click Change settings. If you're prompted for an administrator password or confirmation, type the password or provide confirmation. Move the Hardware Acceleration slider to Full. Full dxdiag dump: ------------------ System Information ------------------ Time of this report: 11/8/2012, 23:13:24 Machine name: DTBARNE Operating System: Windows 7 Professional 64-bit (6.1, Build 7601) Service Pack 1 (7601.win7sp1_gdr.120830-0333) Language: English (Regional Setting: English) System Manufacturer: Dell Inc. System Model: Dell System XPS L502X BIOS: Default System BIOS Processor: Intel(R) Core(TM) i5-2450M CPU @ 2.50GHz (4 CPUs), ~2.5GHz Memory: 8192MB RAM Available OS Memory: 8086MB RAM Page File: 2466MB used, 13704MB available Windows Dir: C:\Windows DirectX Version: DirectX 11 DX Setup Parameters: Not found User DPI Setting: Using System DPI System DPI Setting: 96 DPI (100 percent) DWM DPI Scaling: Disabled DxDiag Version: 6.01.7601.17514 32bit Unicode DxDiag Previously: Crashed in Direct3D (stage 2). Re-running DxDiag with "dontskip" command line parameter or choosing not to bypass information gathering when prompted might result in DxDiag successfully obtaining this information ------------ DxDiag Notes ------------ Display Tab 1: No problems found. Sound Tab 1: No problems found. Sound Tab 2: No problems found. Input Tab: No problems found. -------------------- DirectX Debug Levels -------------------- Direct3D: 0/4 (retail) DirectDraw: 0/4 (retail) DirectInput: 0/5 (retail) DirectMusic: 0/5 (retail) DirectPlay: 0/9 (retail) DirectSound: 0/5 (retail) DirectShow: 0/6 (retail) --------------- Display Devices --------------- Card name: Intel(R) HD Graphics 3000 Manufacturer: Chip type: DAC type: Device Key: Enum\PCI\VEN_8086&DEV_0126&SUBSYS_04B61028&REV_09 Display Memory: Dedicated Memory: n/a Shared Memory: n/a Current Mode: 1920 x 1080 (32 bit) (60Hz) Monitor Name: Generic PnP Monitor Monitor Model: Monitor Id: Native Mode: Output Type: Driver Name: Driver File Version: () Driver Version: DDI Version: Driver Model: WDDM 1.1 Driver Attributes: Final Retail Driver Date/Size: , 0 bytes WHQL Logo'd: n/a WHQL Date Stamp: n/a Device Identifier: Vendor ID: Device ID: SubSys ID: Revision ID: Driver Strong Name: oem11.inf:IntelGfx.NTamd64.6.0:iSNBM0:8.15.10.2696:pci\ven_8086&dev_0126&subsys_04b61028 Rank Of Driver: 00E60001 Video Accel: Deinterlace Caps: n/a D3D9 Overlay: DXVA-HD: DDraw Status: Disabled D3D Status: Not Available AGP Status: Not Available ------------- Sound Devices ------------- Description: Speakers (High Definition Audio Device) Default Sound Playback: Yes Default Voice Playback: Yes Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0665&SUBSYS_102804B6&REV_1000 Manufacturer ID: 1 Product ID: 65535 Type: WDM Driver Name: HdAudio.sys Driver Version: 6.01.7601.17514 (English) Driver Attributes: Final Retail WHQL Logo'd: Yes Date and Size: 11/20/2010 22:23:47, 350208 bytes Other Files: Driver Provider: Microsoft HW Accel Level: Basic Cap Flags: 0xF1F Min/Max Sample Rate: 100, 200000 Static/Strm HW Mix Bufs: 1, 0 Static/Strm HW 3D Bufs: 0, 0 HW Memory: 0 Voice Management: No EAX(tm) 2.0 Listen/Src: No, No I3DL2(tm) Listen/Src: No, No Sensaura(tm) ZoomFX(tm): No Description: Digital Audio (S/PDIF) (High Definition Audio Device) Default Sound Playback: No Default Voice Playback: No Hardware ID: HDAUDIO\FUNC_01&VEN_10EC&DEV_0665&SUBSYS_102804B6&REV_1000 Manufacturer ID: 1 Product ID: 65535 Type: WDM Driver Name: HdAudio.sys Driver Version: 6.01.7601.17514 (English) Driver Attributes: Final Retail WHQL Logo'd: Yes Date and Size: 11/20/2010 22:23:47, 350208 bytes Other Files: Driver Provider: Microsoft HW Accel Level: Basic Cap Flags: 0xF1F Min/Max Sample Rate: 100, 200000 Static/Strm HW Mix Bufs: 1, 0 Static/Strm HW 3D Bufs: 0, 0 HW Memory: 0 Voice Management: No EAX(tm) 2.0 Listen/Src: No, No I3DL2(tm) Listen/Src: No, No Sensaura(tm) ZoomFX(tm): No --------------------- Sound Capture Devices --------------------- Description: Microphone (High Definition Audio Device) Default Sound Capture: Yes Default Voice Capture: Yes Driver Name: HdAudio.sys Driver Version: 6.01.7601.17514 (English) Driver Attributes: Final Retail Date and Size: 11/20/2010 22:23:47, 350208 bytes Cap Flags: 0x1 Format Flags: 0xFFFFF ------------------- DirectInput Devices ------------------- Device Name: Mouse Attached: 1 Controller ID: n/a Vendor/Product ID: n/a FF Driver: n/a Device Name: Keyboard Attached: 1 Controller ID: n/a Vendor/Product ID: n/a FF Driver: n/a Poll w/ Interrupt: No ----------- USB Devices ----------- + USB Root Hub | Vendor/Product ID: 0x8086, 0x1C26 | Matching Device ID: usb\root_hub20 | Service: usbhub | +-+ Generic USB Hub | | Vendor/Product ID: 0x8087, 0x0024 | | Location: Port_#0001.Hub_#0002 | | Matching Device ID: usb\class_09 | | Service: usbhub ---------------- Gameport Devices ---------------- ------------ PS/2 Devices ------------ + Standard PS/2 Keyboard | Matching Device ID: *pnp0303 | Service: i8042prt | + Terminal Server Keyboard Driver | Matching Device ID: root\rdp_kbd | Upper Filters: kbdclass | Service: TermDD | + Synaptics PS/2 Port TouchPad | Matching Device ID: *dll04b6 | Upper Filters: SynTP | Service: i8042prt | + Terminal Server Mouse Driver | Matching Device ID: root\rdp_mou | Upper Filters: mouclass | Service: TermDD ------------------------ Disk & DVD/CD-ROM Drives ------------------------ Drive: C: Free Space: 26.2 GB Total Space: 122.0 GB File System: NTFS Model: M4-CT128M4SSD2 ATA Device Drive: D: Model: Optiarc DVDRWBD BC-5540H ATA Device Driver: c:\windows\system32\drivers\cdrom.sys, 6.01.7601.17514 (English), , 0 bytes -------------- System Devices -------------- Name: High Definition Audio Controller Device ID: PCI\VEN_8086&DEV_1C20&SUBSYS_04B61028&REV_05\3&11583659&0&D8 Driver: n/a Name: PCI standard host CPU bridge Device ID: PCI\VEN_8086&DEV_0104&SUBSYS_04B61028&REV_09\3&11583659&0&00 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C1A&SUBSYS_04B61028&REV_B5\3&11583659&0&E5 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_0101&SUBSYS_20108086&REV_09\3&11583659&0&08 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C18&SUBSYS_04B61028&REV_B5\3&11583659&0&E4 Driver: n/a Name: Intel(R) Centrino(R) Advanced-N 6230 Device ID: PCI\VEN_8086&DEV_0091&SUBSYS_52218086&REV_34\4&2634DE8D&0&00E1 Driver: n/a Name: PCI standard ISA bridge Device ID: PCI\VEN_8086&DEV_1C4B&SUBSYS_04B61028&REV_05\3&11583659&0&F8 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C16&SUBSYS_04B61028&REV_B5\3&11583659&0&E3 Driver: n/a Name: Realtek PCIe GBE Family Controller Device ID: PCI\VEN_10EC&DEV_8168&SUBSYS_04B61028&REV_06\4&109EAB2F&0&00E5 Driver: n/a Name: Intel(R) Management Engine Interface Device ID: PCI\VEN_8086&DEV_1C3A&SUBSYS_04B61028&REV_04\3&11583659&0&B0 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C12&SUBSYS_04B61028&REV_B5\3&11583659&0&E1 Driver: n/a Name: NVIDIA GeForce GT 525M Device ID: PCI\VEN_10DE&DEV_0DF5&SUBSYS_04B61028&REV_A1\4&4DCA75F&0&0008 Driver: n/a Name: Standard Enhanced PCI to USB Host Controller Device ID: PCI\VEN_8086&DEV_1C2D&SUBSYS_04B61028&REV_05\3&11583659&0&D0 Driver: n/a Name: PCI standard PCI-to-PCI bridge Device ID: PCI\VEN_8086&DEV_1C10&SUBSYS_04B61028&REV_B5\3&11583659&0&E0 Driver: n/a Name: Standard Enhanced PCI to USB Host Controller Device ID: PCI\VEN_8086&DEV_1C26&SUBSYS_04B61028&REV_05\3&11583659&0&E8 Driver: n/a Name: Standard AHCI 1.0 Serial ATA Controller Device ID: PCI\VEN_8086&DEV_1C03&SUBSYS_04B61028&REV_05\3&11583659&0&FA Driver: n/a Name: SM Bus Controller Device ID: PCI\VEN_8086&DEV_1C22&SUBSYS_04B61028&REV_05\3&11583659&0&FB Driver: n/a Name: Intel(R) HD Graphics 3000 Device ID: PCI\VEN_8086&DEV_0126&SUBSYS_04B61028&REV_09\3&11583659&0&10 Driver: n/a Name: Renesas Electronics USB 3.0 Host Controller Device ID: PCI\VEN_1033&DEV_0194&SUBSYS_04B61028&REV_04\4&3494AC3A&0&00E3 Driver: n/a ------------------ DirectShow Filters ------------------ DirectShow Filters: WMAudio Decoder DMO,0x00800800,1,1,WMADMOD.DLL,6.01.7601.17514 WMAPro over S/PDIF DMO,0x00600800,1,1,WMADMOD.DLL,6.01.7601.17514 WMSpeech Decoder DMO,0x00600800,1,1,WMSPDMOD.DLL,6.01.7601.17514 MP3 Decoder DMO,0x00600800,1,1,mp3dmod.dll,6.01.7600.16385 Mpeg4s Decoder DMO,0x00800001,1,1,mp4sdecd.dll,6.01.7600.16385 WMV Screen decoder DMO,0x00600800,1,1,wmvsdecd.dll,6.01.7601.17514 WMVideo Decoder DMO,0x00800001,1,1,wmvdecod.dll,6.01.7601.17514 Mpeg43 Decoder DMO,0x00800001,1,1,mp43decd.dll,6.01.7600.16385 Mpeg4 Decoder DMO,0x00800001,1,1,mpg4decd.dll,6.01.7600.16385 DV Muxer,0x00400000,0,0,qdv.dll,6.06.7601.17514 Color Space Converter,0x00400001,1,1,quartz.dll,6.06.7601.17713 WM ASF Reader,0x00400000,0,0,qasf.dll,12.00.7601.17514 Screen Capture filter,0x00200000,0,1,wmpsrcwp.dll,12.00.7601.17514 AVI Splitter,0x00600000,1,1,quartz.dll,6.06.7601.17713 VGA 16 Color Ditherer,0x00400000,1,1,quartz.dll,6.06.7601.17713 SBE2MediaTypeProfile,0x00200000,0,0,sbe.dll,6.06.7601.17528 Microsoft DTV-DVD Video Decoder,0x005fffff,2,4,msmpeg2vdec.dll,6.01.7140.0000 AC3 Parser Filter,0x00600000,1,1,mpg2splt.ax,6.06.7601.17528 StreamBufferSink,0x00200000,0,0,sbe.dll,6.06.7601.17528 MJPEG Decompressor,0x00600000,1,1,quartz.dll,6.06.7601.17713 MPEG-I Stream Splitter,0x00600000,1,2,quartz.dll,6.06.7601.17713 SAMI (CC) Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 VBI Codec,0x00600000,1,4,VBICodec.ax,6.06.7601.17514 MPEG-2 Splitter,0x005fffff,1,0,mpg2splt.ax,6.06.7601.17528 Closed Captions Analysis Filter,0x00200000,2,5,cca.dll,6.06.7601.17514 SBE2FileScan,0x00200000,0,0,sbe.dll,6.06.7601.17528 Microsoft MPEG-2 Video Encoder,0x00200000,1,1,msmpeg2enc.dll,6.01.7601.17514 Internal Script Command Renderer,0x00800001,1,0,quartz.dll,6.06.7601.17713 MPEG Audio Decoder,0x03680001,1,1,quartz.dll,6.06.7601.17713 DV Splitter,0x00600000,1,2,qdv.dll,6.06.7601.17514 Video Mixing Renderer 9,0x00200000,1,0,quartz.dll,6.06.7601.17713 Microsoft MPEG-2 Encoder,0x00200000,2,1,msmpeg2enc.dll,6.01.7601.17514 ACM Wrapper,0x00600000,1,1,quartz.dll,6.06.7601.17713 Video Renderer,0x00800001,1,0,quartz.dll,6.06.7601.17713 MPEG-2 Video Stream Analyzer,0x00200000,0,0,sbe.dll,6.06.7601.17528 Line 21 Decoder,0x00600000,1,1,qdvd.dll,6.06.7601.17835 Video Port Manager,0x00600000,2,1,quartz.dll,6.06.7601.17713 Video Renderer,0x00400000,1,0,quartz.dll,6.06.7601.17713 VPS Decoder,0x00200000,0,0,WSTPager.ax,6.06.7601.17514 WM ASF Writer,0x00400000,0,0,qasf.dll,12.00.7601.17514 VBI Surface Allocator,0x00600000,1,1,vbisurf.ax,6.01.7601.17514 File writer,0x00200000,1,0,qcap.dll,6.06.7601.17514 iTV Data Sink,0x00600000,1,0,itvdata.dll,6.06.7601.17514 iTV Data Capture filter,0x00600000,1,1,itvdata.dll,6.06.7601.17514 DVD Navigator,0x00200000,0,3,qdvd.dll,6.06.7601.17835 Overlay Mixer2,0x00200000,1,1,qdvd.dll,6.06.7601.17835 AVI Draw,0x00600064,9,1,quartz.dll,6.06.7601.17713 RDP DShow Redirection Filter,0xffffffff,1,0,DShowRdpFilter.dll, Microsoft MPEG-2 Audio Encoder,0x00200000,1,1,msmpeg2enc.dll,6.01.7601.17514 WST Pager,0x00200000,1,1,WSTPager.ax,6.06.7601.17514 MPEG-2 Demultiplexer,0x00600000,1,1,mpg2splt.ax,6.06.7601.17528 DV Video Decoder,0x00800000,1,1,qdv.dll,6.06.7601.17514 SampleGrabber,0x00200000,1,1,qedit.dll,6.06.7601.17514 Null Renderer,0x00200000,1,0,qedit.dll,6.06.7601.17514 MPEG-2 Sections and Tables,0x005fffff,1,0,Mpeg2Data.ax,6.06.7601.17514 Microsoft AC3 Encoder,0x00200000,1,1,msac3enc.dll,6.01.7601.17514 StreamBufferSource,0x00200000,0,0,sbe.dll,6.06.7601.17528 Smart Tee,0x00200000,1,2,qcap.dll,6.06.7601.17514 Overlay Mixer,0x00200000,0,0,qdvd.dll,6.06.7601.17835 AVI Decompressor,0x00600000,1,1,quartz.dll,6.06.7601.17713 AVI/WAV File Source,0x00400000,0,2,quartz.dll,6.06.7601.17713 Wave Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 MIDI Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 Multi-file Parser,0x00400000,1,1,quartz.dll,6.06.7601.17713 File stream renderer,0x00400000,1,1,quartz.dll,6.06.7601.17713 Microsoft DTV-DVD Audio Decoder,0x005fffff,1,1,msmpeg2adec.dll,6.01.7140.0000 StreamBufferSink2,0x00200000,0,0,sbe.dll,6.06.7601.17528 AVI Mux,0x00200000,1,0,qcap.dll,6.06.7601.17514 Line 21 Decoder 2,0x00600002,1,1,quartz.dll,6.06.7601.17713 File Source (Async.),0x00400000,0,1,quartz.dll,6.06.7601.17713 File Source (URL),0x00400000,0,1,quartz.dll,6.06.7601.17713 Infinite Pin Tee Filter,0x00200000,1,1,qcap.dll,6.06.7601.17514 Enhanced Video Renderer,0x00200000,1,0,evr.dll,6.01.7601.17514 BDA MPEG2 Transport Information Filter,0x00200000,2,0,psisrndr.ax,6.06.7601.17669 MPEG Video Decoder,0x40000001,1,1,quartz.dll,6.06.7601.17713 WDM Streaming Tee/Splitter Devices: Tee/Sink-to-Sink Converter,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 Video Compressors: WMVideo8 Encoder DMO,0x00600800,1,1,wmvxencd.dll,6.01.7600.16385 WMVideo9 Encoder DMO,0x00600800,1,1,wmvencod.dll,6.01.7600.16385 MSScreen 9 encoder DMO,0x00600800,1,1,wmvsencd.dll,6.01.7600.16385 DV Video Encoder,0x00200000,0,0,qdv.dll,6.06.7601.17514 MJPEG Compressor,0x00200000,0,0,quartz.dll,6.06.7601.17713 Cinepak Codec by Radius,0x00200000,1,1,qcap.dll,6.06.7601.17514 Intel IYUV codec,0x00200000,1,1,qcap.dll,6.06.7601.17514 Intel IYUV codec,0x00200000,1,1,qcap.dll,6.06.7601.17514 Microsoft RLE,0x00200000,1,1,qcap.dll,6.06.7601.17514 Microsoft Video 1,0x00200000,1,1,qcap.dll,6.06.7601.17514 Audio Compressors: WM Speech Encoder DMO,0x00600800,1,1,WMSPDMOE.DLL,6.01.7600.16385 WMAudio Encoder DMO,0x00600800,1,1,WMADMOE.DLL,6.01.7600.16385 IMA ADPCM,0x00200000,1,1,quartz.dll,6.06.7601.17713 PCM,0x00200000,1,1,quartz.dll,6.06.7601.17713 Microsoft ADPCM,0x00200000,1,1,quartz.dll,6.06.7601.17713 GSM 6.10,0x00200000,1,1,quartz.dll,6.06.7601.17713 CCITT A-Law,0x00200000,1,1,quartz.dll,6.06.7601.17713 CCITT u-Law,0x00200000,1,1,quartz.dll,6.06.7601.17713 MPEG Layer-3,0x00200000,1,1,quartz.dll,6.06.7601.17713 Audio Capture Sources: Microphone (High Definition Aud,0x00200000,0,0,qcap.dll,6.06.7601.17514 PBDA CP Filters: PBDA DTFilter,0x00600000,1,1,CPFilters.dll,6.06.7601.17528 PBDA ETFilter,0x00200000,0,0,CPFilters.dll,6.06.7601.17528 PBDA PTFilter,0x00200000,0,0,CPFilters.dll,6.06.7601.17528 Midi Renderers: Default MidiOut Device,0x00800000,1,0,quartz.dll,6.06.7601.17713 Microsoft GS Wavetable Synth,0x00200000,1,0,quartz.dll,6.06.7601.17713 WDM Streaming Capture Devices: HD Audio Microphone 2,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 Integrated Webcam,0x00200000,1,2,ksproxy.ax,6.01.7601.17514 WDM Streaming Rendering Devices: HD Audio Headphone/Speakers,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 HD Audio SPDIF out,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 BDA Network Providers: Microsoft ATSC Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft DVBC Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft DVBS Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft DVBT Network Provider,0x00200000,0,1,MSDvbNP.ax,6.06.7601.17514 Microsoft Network Provider,0x00200000,0,1,MSNP.ax,6.06.7601.17514 Video Capture Sources: Integrated Webcam,0x00200000,1,2,ksproxy.ax,6.01.7601.17514 Multi-Instance Capable VBI Codecs: VBI Codec,0x00600000,1,4,VBICodec.ax,6.06.7601.17514 BDA Transport Information Renderers: BDA MPEG2 Transport Information Filter,0x00600000,2,0,psisrndr.ax,6.06.7601.17669 MPEG-2 Sections and Tables,0x00600000,1,0,Mpeg2Data.ax,6.06.7601.17514 BDA CP/CA Filters: Decrypt/Tag,0x00600000,1,1,EncDec.dll,6.06.7601.17708 Encrypt/Tag,0x00200000,0,0,EncDec.dll,6.06.7601.17708 PTFilter,0x00200000,0,0,EncDec.dll,6.06.7601.17708 XDS Codec,0x00200000,0,0,EncDec.dll,6.06.7601.17708 WDM Streaming Communication Transforms: Tee/Sink-to-Sink Converter,0x00200000,1,1,ksproxy.ax,6.01.7601.17514 Audio Renderers: Speakers (High Definition Audio,0x00200000,1,0,quartz.dll,6.06.7601.17713 Default DirectSound Device,0x00800000,1,0,quartz.dll,6.06.7601.17713 Default WaveOut Device,0x00200000,1,0,quartz.dll,6.06.7601.17713 Digital Audio (S/PDIF) (High De,0x00200000,1,0,quartz.dll,6.06.7601.17713 DirectSound: Digital Audio (S/PDIF) (High Definition Audio Device),0x00200000,1,0,quartz.dll,6.06.7601.17713 DirectSound: Speakers (High Definition Audio Device),0x00200000,1,0,quartz.dll,6.06.7601.17713 --------------- EVR Power Information --------------- Current Setting: {651288E5-A7ED-4076-A96B-6CC62D848FE1} (Balanced) Quality Flags: 2576 Enabled: Force throttling Allow half deinterlace Allow scaling Decode Power Usage: 100 Balanced Flags: 1424 Enabled: Force throttling Allow batching Force half deinterlace Force scaling Decode Power Usage: 50 PowerFlags: 1424 Enabled: Force throttling Allow batching Force half deinterlace Force scaling Decode Power Usage: 0

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• 10 Essential Tools for building ASP.NET Websites

  - by Stephen Walther

  I recently put together a simple public website created with ASP.NET for my company at Superexpert.com. I was surprised by the number of free tools that I ended up using to put together the website. Therefore, I thought it would be interesting to create a list of essential tools for building ASP.NET websites. These tools work equally well with both ASP.NET Web Forms and ASP.NET MVC. Performance Tools After reading Steve Souders two (very excellent) books on front-end website performance High Performance Web Sites and Even Faster Web Sites, I have been super sensitive to front-end website performance. According to Souders’ Performance Golden Rule: “Optimize front-end performance first, that's where 80% or more of the end-user response time is spent” You can use the tools below to reduce the size of the images, JavaScript files, and CSS files used by an ASP.NET application. 1. Sprite and Image Optimization Framework CSS sprites were first described in an article written for A List Apart entitled CSS sprites: Image Slicing’s Kiss of Death. When you use sprites, you combine multiple images used by a website into a single image. Next, you use CSS trickery to display particular sub-images from the combined image in a webpage. The primary advantage of sprites is that they reduce the number of requests required to display a webpage. Requesting a single large image is faster than requesting multiple small images. In general, the more resources – images, JavaScript files, CSS files – that must be moved across the wire, the slower your website. However, most people avoid using sprites because they require a lot of work. You need to combine all of the images and write just the right CSS rules to display the sub-images. The Microsoft Sprite and Image Optimization Framework enables you to avoid all of this work. The framework combines the images for you automatically. Furthermore, the framework includes an ASP.NET Web Forms control and an ASP.NET MVC helper that makes it easy to display the sub-images. You can download the Sprite and Image Optimization Framework from CodePlex at http://aspnet.codeplex.com/releases/view/50869. The Sprite and Image Optimization Framework was written by Morgan McClean who worked in the office next to mine at Microsoft. Morgan was a scary smart Intern from Canada and we discussed the Framework while he was building it (I was really excited to learn that he was working on it). Morgan added some great advanced features to this framework. For example, the Sprite and Image Optimization Framework supports something called image inlining. When you use image inlining, the actual image is stored in the CSS file. Here’s an example of what image inlining looks like: .Home_StephenWalther_small-jpg { width:75px; height:100px; background: url(data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAEsAAABkCAIAAABB1lpeAAAAB GdBTUEAALGOfPtRkwAAACBjSFJNAACHDwAAjA8AAP1SAACBQAAAfXkAAOmLAAA85QAAGcxzPIV3AAAKL s+zNfREAAAAASUVORK5CYII=) no-repeat 0% 0%; } The actual image (in this case a picture of me that is displayed on the home page of the Superexpert.com website) is stored in the CSS file. If you visit the Superexpert.com website then very few separate images are downloaded. For example, all of the images with a red border in the screenshot below take advantage of CSS sprites: Unfortunately, there are some significant Gotchas that you need to be aware of when using the Sprite and Image Optimization Framework. There are workarounds for these Gotchas. I plan to write about these Gotchas and workarounds in a future blog entry. 2. Microsoft Ajax Minifier Whenever possible you should combine, minify, compress, and cache with a far future header all of your JavaScript and CSS files. The Microsoft Ajax Minifier makes it easy to minify JavaScript and CSS files. Don’t confuse minification and compression. You need to do both. According to Souders, you can reduce the size of a JavaScript file by an additional 20% (on average) by minifying a JavaScript file after you compress the file. When you minify a JavaScript or CSS file, you use various tricks to reduce the size of the file before you compress the file. For example, you can minify a JavaScript file by replacing long JavaScript variables names with short variables names and removing unnecessary white space and comments. You can minify a CSS file by doing such things as replacing long color names such as #ffffff with shorter equivalents such as #fff. The Microsoft Ajax Minifier was created by Microsoft employee Ron Logan. Internally, this tool was being used by several large Microsoft websites. We also used the tool heavily on the ASP.NET team. I convinced Ron to publish the tool on CodePlex so that everyone in the world could take advantage of it. You can download the tool from the ASP.NET Ajax website and read documentation for the tool here. I created the installer for the Microsoft Ajax Minifier. When creating the installer, I also created a Visual Studio build task to make it easy to minify all of your JavaScript and CSS files whenever you do a build within Visual Studio automatically. Read the Ajax Minifier Quick Start to learn how to configure the build task. 3. ySlow The ySlow tool is a free add-on for Firefox created by Yahoo that enables you to test the front-end of your website. For example, here are the current test results for the Superexpert.com website: The Superexpert.com website has an overall score of B (not perfect but not bad). The ySlow tool is not perfect. For example, the Superexpert.com website received a failing grade of F for not using a Content Delivery Network even though the website using the Microsoft Ajax Content Delivery Network for JavaScript files such as jQuery. Uptime After publishing a website live to the world, you want to ensure that the website does not encounter any issues and that it stays live. I use the following tools to monitor the Superexpert.com website now that it is live. 4. ELMAH ELMAH stands for Error Logging Modules and Handlers for ASP.NET. ELMAH enables you to record any errors that happen at your website so you can review them in the future. You can download ELMAH for free from the ELMAH project website. ELMAH works great with both ASP.NET Web Forms and ASP.NET MVC. You can configure ELMAH to store errors in a number of different stores including XML files, the Event Log, an Access database, a SQL database, an Oracle database, or in computer RAM. You also can configure ELMAH to email error messages to you when they happen. By default, you can access ELMAH by requesting the elmah.axd page from a website with ELMAH installed. Here’s what the elmah page looks like from the Superexpert.com website (this page is password-protected because secret information can be revealed in an error message): If you click on a particular error message, you can view the original Yellow Screen ASP.NET error message (even when the error message was never displayed to the actual user). I installed ELMAH by taking advantage of the new package manager for ASP.NET named NuGet (originally named NuPack). You can read the details about NuGet in the following blog entry by Scott Guthrie. You can download NuGet from CodePlex. 5. Pingdom I use Pingdom to verify that the Superexpert.com website is always up. You can sign up for Pingdom by visiting Pingdom.com. You can use Pingdom to monitor a single website for free. At the Pingdom website, you configure the frequency that your website gets pinged. I verify that the Superexpert.com website is up every 5 minutes. I have the Pingdom service verify that it can retrieve the string “Contact Us” from the website homepage. If your website goes down, you can configure Pingdom so that it sends an email, Twitter, SMS, or iPhone alert. I use the Pingdom iPhone app which looks like this: 6. Host Tracker If your website does go down then you need some way of determining whether it is a problem with your local network or if your website is down for everyone. I use a website named Host-Tracker.com to check how badly a website is down. Here’s what the Host-Tracker website displays for the Superexpert.com website when the website can be successfully pinged from everywhere in the world: Notice that Host-Tracker pinged the Superexpert.com website from 68 locations including Roubaix, France and Scranton, PA. Debugging I mean debugging in the broadest possible sense. I use the following tools when building a website to verify that I have not made a mistake. 7. HTML Spell Checker Why doesn’t Visual Studio have a built-in spell checker? Don’t know – I’ve always found this mysterious. Fortunately, however, a former member of the ASP.NET team wrote a free spell checker that you can use with your ASP.NET pages. I find a spell checker indispensible. It is easy to delude yourself that you are capable of perfect spelling. I’m always super embarrassed when I actually run the spell checking tool and discover all of my spelling mistakes. The fastest way to add the HTML Spell Checker extension to Visual Studio is to select the menu option Tools, Extension Manager within Visual Studio. Click on Online Gallery and search for HTML Spell Checker: 8. IIS SEO Toolkit If people cannot find your website through Google then you should not even bother to create it. Microsoft has a great extension for IIS named the IIS Search Engine Optimization Toolkit that you can use to identify issue with your website that would hurt its page rank. You also can use this tool to quickly create a sitemap for your website that you can submit to Google or Bing. You can even generate the sitemap for an ASP.NET MVC website. Here’s what the report overview for the Superexpert.com website looks like: Notice that the Sueprexpert.com website had plenty of violations. For example, there are 65 cases in which a page has a broken hyperlink. You can drill into these violations to identity the exact page and location where these violations occur. 9. LinqPad If your ASP.NET website accesses a database then you should be using LINQ to Entities with the Entity Framework. Using LINQ involves some magic. LINQ queries written in C# get converted into SQL queries for you. If you are not careful about how you write your LINQ queries, you could unintentionally build a really badly performing website. LinqPad is a free tool that enables you to experiment with your LINQ queries. It even works with Microsoft SQL CE 4 and Azure. You can use LinqPad to execute a LINQ to Entities query and see the results. You also can use it to see the resulting SQL that gets executed against the database: 10. .NET Reflector I use .NET Reflector daily. The .NET Reflector tool enables you to take any assembly and disassemble the assembly into C# or VB.NET code. You can use .NET Reflector to see the “Source Code” of an assembly even when you do not have the actual source code. You can download a free version of .NET Reflector from the Redgate website. I use .NET Reflector primarily to help me understand what code is doing internally. For example, I used .NET Reflector with the Sprite and Image Optimization Framework to better understand how the MVC Image helper works. Here’s part of the disassembled code from the Image helper class: Summary In this blog entry, I’ve discussed several of the tools that I used to create the Superexpert.com website. These are tools that I use to improve the performance, improve the SEO, verify the uptime, or debug the Superexpert.com website. All of the tools discussed in this blog entry are free. Furthermore, all of these tools work with both ASP.NET Web Forms and ASP.NET MVC. Let me know if there are any tools that you use daily when building ASP.NET websites.

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• CLSF & CLK 2013 Trip Report by Jeff Liu

  - by jamesmorris

  This is a contributed post from Jeff Liu, lead XFS developer for the Oracle mainline Linux kernel team. Recently, I attended both the China Linux Storage and Filesystem workshop (CLSF), and the China Linux Kernel conference (CLK), which were held in Shanghai. Here are the highlights for both events. CLSF - 17th October XFS update (led by Jeff Liu) XFS keeps rapid progress with a lot of changes, especially focused on the infrastructure/performance improvements as well as  new feature development.  This can be reflected with a sample statistics among XFS/Ext4+JBD2/Btrfs via: # git diff --stat --minimal -C -M v3.7..v3.12-rc4 -- fs/xfs|fs/ext4+fs/jbd2|fs/btrfs XFS: 141 files changed, 27598 insertions(+), 19113 deletions(-) Ext4+JBD2: 39 files changed, 10487 insertions(+), 5454 deletions(-) Btrfs: 70 files changed, 19875 insertions(+), 8130 deletions(-) What made up those changes in XFS? Self-describing metadata(CRC32c). This is a new feature and it contributed about 70% code changes, it can be enabled via `mkfs.xfs -m crc=1 /dev/xxx` for v5 superblock. Transaction log space reservation improvements. With this change, we can calculate the log space reservation at mount time rather than runtime to reduce the the CPU overhead. User namespace support. So both XFS and USERNS can be enabled on kernel configuration begin from Linux 3.10. Thanks Dwight Engen's efforts for this thing. Split project/group quota inodes. Originally, project quota can not be enabled with group quota at the same time because they were share the same quota file inode, now it works but only for v5 super block. i.e, CRC enabled. CONFIG_XFS_WARN, an new lightweight runtime debugger which can be deployed in production environment. Readahead log object recovery, this change can speed up the log replay progress significantly. Speculative preallocation inode tracking, clearing and throttling. The main purpose is to deal with inodes with post-EOF space due to speculative preallocation, support improved quota management to free up a significant amount of unwritten space when at or near EDQUOT. It support backgroup scanning which occurs on a longish interval(5 mins by default, tunable), and on-demand scanning/trimming via ioctl(2). Bitter arguments ensued from this session, especially for the comparison between Ext4 and Btrfs in different areas, I have to spent a whole morning of the 1st day answering those questions. We basically agreed on XFS is the best choice in Linux nowadays because: Stable, XFS has a good record in stability in the past 10 years. Fengguang Wu who lead the 0-day kernel test project also said that he has observed less error than other filesystems in the past 1+ years, I own it to the XFS upstream code reviewer, they always performing serious code review as well as testing. Good performance for large/small files, XFS does not works very well for small files has already been an old story for years. Best choice (maybe) for distributed PB filesystems. e.g, Ceph recommends delopy OSD daemon on XFS because Ext4 has limited xattr size. Best choice for large storage (>16TB). Ext4 does not support a single file more than around 15.95TB. Scalability, any objection to XFS is best in this point? :) XFS is better to deal with transaction concurrency than Ext4, why? The maximum size of the log in XFS is 2038MB compare to 128MB in Ext4. Misc. Ext4 is widely used and it has been proved fast/stable in various loads and scenarios, XFS just need more customers, and Btrfs is still on the road to be a manhood. Ceph Introduction (Led by Li Wang) This a hot topic.  Li gave us a nice introduction about the design as well as their current works. Actually, Ceph client has been included in Linux kernel since 2.6.34 and supported by Openstack since Folsom but it seems that it has not yet been widely deployment in production environment. Their major work is focus on the inline data support to separate the metadata and data storage, reduce the file access time, i.e, a file access need communication twice, fetch the metadata from MDS and then get data from OSD, and also, the small file access is limited by the network latency. The solution is, for the small files they would like to store the data at metadata so that when accessing a small file, the metadata server can push both metadata and data to the client at the same time. In this way, they can reduce the overhead of calculating the data offset and save the communication to OSD. For this feature, they have only run some small scale testing but really saw noticeable improvements. Test environment: Intel 2 CPU 12 Core, 64GB RAM, Ubuntu 12.04, Ceph 0.56.6 with 200GB SATA disk, 15 OSD, 1 MDS, 1 MON. The sequence read performance for 1K size files improved about 50%. I have asked Li and Zheng Yan (the core developer of Ceph, who also worked on Btrfs) whether Ceph is really stable and can be deployed at production environment for large scale PB level storage, but they can not give a positive answer, looks Ceph even does not spread over Dreamhost (subject to confirmation). From Li, they only deployed Ceph for a small scale storage(32 nodes) although they'd like to try 6000 nodes in the future. Improve Linux swap for Flash storage (led by Shaohua Li) Because of high density, low power and low price, flash storage (SSD) is a good candidate to partially replace DRAM. A quick answer for this is using SSD as swap. But Linux swap is designed for slow hard disk storage, so there are a lot of challenges to efficiently use SSD for swap. SWAPOUT swap_map scan swap_map is the in-memory data structure to track swap disk usage, but it is a slow linear scan. It will become a bottleneck while finding many adjacent pages in the use of SSD. Shaohua Li have changed it to a cluster(128K) list, resulting in O(1) algorithm. However, this apporoach needs restrictive cluster alignment and only enabled for SSD. IO pattern In most cases, the swap io is in interleaved pattern because of mutiple reclaimers or a free cluster is shared by all reclaimers. Even though block layer can merge interleaved IO to some extent, but we cannot count on it completely. Hence the per-cpu cluster is added base on the previous change, it can help reclaimer do sequential IO and the block layer will be easier to merge IO. TLB flush: If we're reclaiming one active page, we should first move the page from active lru list to inactive lru list, and then reclaim the page from inactive lru to swap it out. During the process, we need to clear PTE twice: first is 'A'(ACCESS) bit, second is 'P'(PRESENT) bit. Processors need to send lots of ipi which make the TLB flush really expensive. Some works have been done to improve this, including rework smp_call_functiom_many() or remove the first TLB flush in x86, but there still have some arguments here and only parts of works have been pushed to mainline. SWAPIN: Page fault does iodepth=1 sync io, but it's a little waste if only issue a page size's IO. The obvious solution is doing swap readahead. But the current in-kernel swap readahead is arbitary(always 8 pages), and it always doesn't perform well for both random and sequential access workload. Shaohua introduced a new flag for madvise(MADV_WILLNEED) to do swap prefetch, so the changes happen in userspace API and leave the in-kernel readahead unchanged(but I think some improvement can also be done here). SWAP discard As we know, discard is important for SSD write throughout, but the current swap discard implementation is synchronous. He changed it to async discard which allow discard and write run in the same time. Meanwhile, the unit of discard is also optimized to cluster. Misc: lock contention For many concurrent swapout and swapin , the lock contention such as anon_vma or swap_lock is high, so he changed the swap_lock to a per-swap lock. But there still have some lock contention in very high speed SSD because of swapcache address_space lock. Zproject (led by Bob Liu) Bob gave us a very nice introduction about the current memory compression status. Now there are 3 projects(zswap/zram/zcache) which all aim at smooth swap IO storm and promote performance, but they all have their own pros and cons. ZSWAP It is implemented based on frontswap API and it uses a dynamic allocater named Zbud to allocate free pages. Zbud means pairs of zpages are "buddied" and it can only store at most two compressed pages in one page frame, so the max compress ratio is 50%. Each page frame is lru-linked and can do shink in memory pressure. If the compressed memory pool reach its limitation, shink or reclaim happens. It decompress the page frame into two new allocated pages and then write them to real swap device, but it can fail when allocating the two pages. ZRAM Acts as a compressed ramdisk and used as swap device, and it use zsmalloc as its allocator which has high density but may have fragmentation issues. Besides, page reclaim is hard since it will need more pages to uncompress and free just one page. ZRAM is preferred by embedded system which may not have any real swap device. Now both ZRAM and ZSWAP are in driver/staging tree, and in the mm community there are some disscussions of merging ZRAM into ZSWAP or viceversa, but no agreement yet. ZCACHE Handles file page compression but it is removed out of staging recently. From industry (led by Tang Jie, LSI) An LSI engineer introduced several new produces to us. The first is raid5/6 cards that it use full stripe writes to improve performance. The 2nd one he introduced is SandForce flash controller, who can understand data file types (data entropy) to reduce write amplification (WA) for nearly all writes. It's called DuraWrite and typical WA is 0.5. What's more, if enable its Dynamic Logical Capacity function module, the controller can do data compression which is transparent to upper layer. LSI testing shows that with this virtual capacity enables 1x TB drive can support up to 2x TB capacity, but the application must monitor free flash space to maintain optimal performance and to guard against free flash space exhaustion. He said the most useful application is for datebase. Another thing I think it's worth to mention is that a NV-DRAM memory in NMR/Raptor which is directly exposed to host system. Applications can directly access the NV-DRAM via a memory address - using standard system call mmap(). He said that it is very useful for database logging now. This kind of NVM produces are beginning to appear in recent years, and it is said that Samsung is building a research center in China for related produces. IMHO, NVM will bring an effect to current os layer especially on file system, e.g. its journaling may need to redesign to fully utilize these nonvolatile memory. OCFS2 (led by Canquan Shen) Without a doubt, HuaWei is the biggest contributor to OCFS2 in the past two years. They have posted 46 upstream patches and 39 patches have been merged. Their current project is based on 32/64 nodes cluster, but they also tried 128 nodes at the experimental stage. The major work they are working is to support ATS (atomic test and set), it can be works with DLM at the same time. Looks this idea is inspired by the vmware VMFS locking, i.e, http://blogs.vmware.com/vsphere/2012/05/vmfs-locking-uncovered.html CLK - 18th October 2013 Improving Linux Development with Better Tools (Andi Kleen) This talk focused on how to find/solve bugs along with the Linux complexity growing. Generally, we can do this with the following kind of tools: Static code checkers tools. e.g, sparse, smatch, coccinelle, clang checker, checkpatch, gcc -W/LTO, stanse. This can help check a lot of things, simple mistakes, complex problems, but the challenges are: some are very slow, false positives, may need a concentrated effort to get false positives down. Especially, no static checker I found can follow indirect calls (“OO in C”, common in kernel): struct foo_ops { int (*do_foo)(struct foo *obj); } foo->do_foo(foo); Dynamic runtime checkers, e.g, thread checkers, kmemcheck, lockdep. Ideally all kernel code would come with a test suite, then someone could run all the dynamic checkers. Fuzzers/test suites. e.g, Trinity is a great tool, it finds many bugs, but needs manual model for each syscall. Modern fuzzers around using automatic feedback, but notfor kernel yet: http://taviso.decsystem.org/making_software_dumber.pdf Debuggers/Tracers to understand code, e.g, ftrace, can dump on events/oops/custom triggers, but still too much overhead in many cases to run always during debug. Tools to read/understand source, e.g, grep/cscope work great for many cases, but do not understand indirect pointers (OO in C model used in kernel), give us all “do_foo” instances: struct foo_ops { int (*do_foo)(struct foo *obj); } = { .do_foo = my_foo }; foo>do_foo(foo); That would be great to have a cscope like tool that understands this based on types/initializers XFS: The High Performance Enterprise File System (Jeff Liu) [slides] I gave a talk for introducing the disk layout, unique features, as well as the recent changes.   The slides include some charts to reflect the performances between XFS/Btrfs/Ext4 for small files. About a dozen users raised their hands when I asking who has experienced with XFS. I remembered that when I asked the same question in LinuxCon/Japan, only 3 people raised their hands, but they are Chris Mason, Ric Wheeler, and another attendee. The attendee questions were mainly focused on stability, and comparison with other file systems. Linux Containers (Feng Gao) The speaker introduced us that the purpose for those kind of namespaces, include mount/UTS/IPC/Network/Pid/User, as well as the system API/ABI. For the userspace tools, He mainly focus on the Libvirt LXC rather than us(LXC). Libvirt LXC is another userspace container management tool, implemented as one type of libvirt driver, it can manage containers, create namespace, create private filesystem layout for container, Create devices for container and setup resources controller via cgroup. In this talk, Feng also mentioned another two possible new namespaces in the future, the 1st is the audit, but not sure if it should be assigned to user namespace or not. Another is about syslog, but the question is do we really need it? In-memory Compression (Bob Liu) Same as CLSF, a nice introduction that I have already mentioned above. Misc There were some other talks related to ACPI based memory hotplug, smart wake-affinity in scheduler etc., but my head is not big enough to record all those things. -- Jeff Liu

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• _default_ VirtualHost overlap on port 443, the first has precedence

  - by Mohit Jain

  I have two ruby on rails 3 applications running on same server, (ubuntu 10.04), both with SSL. Here is my apache config file: <VirtualHost *:80> ServerName example1.com DocumentRoot /home/me/example1/production/current/public </VirtualHost> <VirtualHost *:443> ServerName example1.com DocumentRoot /home/me/example1/production/current/public SSLEngine on SSLCertificateFile /home/me/example1/production/shared/example1.crt SSLCertificateKeyFile /home/me/example1/production/shared/example1.key SSLCertificateChainFile /home/me/example1/production/shared/gd_bundle.crt SSLProtocol -all +TLSv1 +SSLv3 SSLCipherSuite HIGH:MEDIUM:!aNULL:+SHA1:+MD5:+HIGH:+MEDIUM </VirtualHost> <VirtualHost *:80> ServerName example2.com DocumentRoot /home/me/example2/production/current/public </VirtualHost> <VirtualHost *:443> ServerName example2.com DocumentRoot /home/me/example2/production/current/public SSLEngine on SSLCertificateFile /home/me/example2/production/shared/iwanto.crt SSLCertificateKeyFile /home/me/example2/production/shared/iwanto.key SSLCertificateChainFile /home/me/example2/production/shared/gd_bundle.crt SSLProtocol -all +TLSv1 +SSLv3 SSLCipherSuite HIGH:MEDIUM:!aNULL:+SHA1:+MD5:+HIGH:+MEDIUM </VirtualHost> Whats the issue: On restarting my server it gives me some output like this: * Restarting web server apache2 [Sun Jun 17 17:57:49 2012] [warn] _default_ VirtualHost overlap on port 443, the first has precedence ... waiting [Sun Jun 17 17:57:50 2012] [warn] _default_ VirtualHost overlap on port 443, the first has precedence On googling why this issue is coming I got something like this: You cannot use name based virtual hosts with SSL because the SSL handshake (when the browser accepts the secure Web server's certificate) occurs before the HTTP request, which identifies the appropriate name based virtual host. If you plan to use name-based virtual hosts, remember that they only work with your non-secure Web server. But not able to figure out how to run two ssl application on same server. Can any one help me?

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