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  • A Forming Repository of Script Samples for Automating Windows Server 2012 and Windows 8

    - by Jialiang
    Compared with Windows Server 2008/R2 that provides about 230 cmdlets, Windows Server 2012 beats that by a factor of over 10 shipping ~ 2,430 cmdlets.  You can automate almost every aspect of the server.   The new PowerShell 3.0, like Windows Server 2012, has a ton of new features.  In this automation script-centric move, Microsoft All-In-One Script Framework (AIOSF) is ready to support IT Pros with many new services and offerings coming this year.  We sincerely hope that the IT community will benefit from the effort. Here is the first one among our new services and offerings:  The team is preparing a large set of Windows 8 / Windows Server 2012 script samples based on frequently asked IT tasks that we collect in TechNet forums and support calls to Microsoft.   Because the script topics come from frequently asked IT tasks, we hope that these script samples can be helpful to many IT Pros worldwide.   With the General Availability of Windows Server 2012, we release the first three Windows Server 2012 / Windows 8 script samples today.    Get Network Adapter Properties in Windows Server 2012 and Windows 8 (PowerShell) http://gallery.technet.microsoft.com/scriptcenter/Get-Network-Adapter-37c5a913 Description: This script could be used to get network adapter properties and advanced properties in Windows Server 2012 and Windows 8. It combines the outputs of Get-NetAdapter and Get-NetAdapterAdvancedProperty. It can generate a report of network adapter configuration settings. Use Scenarios: In a real world, IT Administrators are required to check the configuration of network adapters after the deployment of new servers. One typical example is the duplex setting of network adapters. Also, IT administrators need to maintain a server list which contains network adapter configuration settings in a regular basis. Before Windows Server 2012, IT administrators often feel difficulties to handle these tasks. Acknowledgement: Thanks Greg Gu from AIOSF for collecting this script topic, and writing the script sample.  Thanks James Adams (Microsoft Premier Field Engineer) for reviewing the script sample and ensuring its quality.   How to batch create virtual machines in Windows Server 2012 (PowerShell) http://gallery.technet.microsoft.com/scriptcenter/How-to-batch-create-9efd1811 Description: This PowerShell Script illustrates how to batch create multiple virtual machines based on comma delimited file by using PowerShell 3.0 in Windows Server 2012. Use Scenarios: IT admin requires to batch creating virtual machines in Windows Server 2012, although they can use few commands due to the lack of programming knowledge. Although it’s a set of Hyper-V command-lets within Windows PowerShell, IT Admins are reluctant to use them except simple a command which is widely used. Acknowledgement: Thanks Anders Wang from AIOSF for collecting this script topic and writing the script sample.  Thanks Christopher Norris for reviewing the script sample and ensuring its quality before publishing.   Remove Windows Store Apps in Windows 8 (PowerShell) http://gallery.technet.microsoft.com/scriptcenter/Remove-Windows-Store-Apps-a00ef4a4 Description: This script can be used to remove multiple Windows Store Apps from a user account in Windows 8. It provides a list of installed Windows Store applications. You can specify the application IDs, and remove them all at once. Use Scenarios: 1. In Windows 8, you can remove a single Windows Store App by right-clicking the tile in the Start menu and choosing the uninstall command.  However, no command is provided for removing multiple Windows Store Apps all at once. If you want to do so, you can use this script sample. 2. Sometimes Windows Store Apps may crash in Windows 8.  Even though you can successfully uninstall and reinstall the App, the application may still crash after the reinstallation.  In this situation, you can use this example script to remove these Windows Store Apps cleanly. Acknowledgement: Thanks Edward Qi from AIOSF for collecting the script idea and composing the script sample.  Thanks James Adams (Microsoft Premier Field Engineer) for reviewing the script sample and ensuring its quality.   This is just the beginning, and more and more script samples are coming.  You can follow our blog (http://blogs.technet.com/b/onescript) to get the latest customer-driven script samples for Windows Server 2012 and Windows 8.

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  • WebCenter Marketing and Upcoming Events

    - by rituchhibber
    Events: Events: Date Event Name Location/Country October 30, 2012 ResCare Solves Content Lifecycle Challenges with Oracle WebCenter Webcast November 1, 2012 Paper Burying Your HR Processes? Dig Your Way Out With Oracle WebCenter! Webcast November 15, 2012 Social Business Thought Leader Webcast: Three Ways to Fix Your Broken Organization, featuring Christian Finn Webcast Marketing: Marketing: WebCenter Sites Sales eVite:Embrace the Base: Create an Exceptional Online Customer Experience with Oracle WebCenter Sites Directs recipients to the Connected Customer Experience Resource Center to see the latest demos, analyst reports, and customer webcasts promoting WebCenter Sites. For more information Click  here. WebCenter Social Business Thought Leaders Series: Digital Darwinism: How Brands Can Survive the Rapid Evolution of Society and TechnologyBrian Solis, Altimeter Group digital analyst and futuristDecember 13, 2012 10am PDTRegistration available soon, find other content from this speaker here. Webcast: WebCenter Sites for Applications: Disconnected Online Customer Experience? Connect it with Oracle WebCenter November 8, 2012  eVite | Registration Page WebCenter in Action Customer & Partner webcast series: Started earlier in FY13, a new webcast series featuring WebCenter customer deployments that are executed by a partner.The next webcast in the series will be November 14th:Los Angeles Department of Building & Safety Lowers Customer Service Costs with Oracle WebCenter Click here to learn more. OnDemand Webcast: ResCare Solves Content Lifecycle Challenges with Oracle WebCenterComplex documents must be created, assembled, reviewed, and tracked. To avoid fragmented, chaotic information processes, organizations must adopt an integrated set of strategies, standards, best practices, and technologies for managing information. Attend this webcast to learn how Oracle WebCenter has allowed ResCare to: solve content lifecycle challenges, reduce compliance and business risks and increase adoption of intranet as primary business communication tool. On-Demand Assets Date Event Name Location/Country On Demand Avoid Social Media Fatigue - Learn the 9 C’s of Customer Engagement, featuring Ray Wang, Principal Analyst and CEO, Constellation Research Webcast On Demand WebCenter in Action Series: Hitachi Data Systems Improves Global Web Experience with Oracle WebCenter, presented by Hitachi Data Systems and Lingotek. Webcast On Demand Managing Social Relationships for the Enterprise, featuring Jeremiah Owyang, Industry Analyst, Altimeter Group and Reggie Bradford, Vice President, Oracle Webcast On Demand Oracle’s Vision for the Social-Enabled Enterprise, presented by Mark Hurd, Thomas Kurian and Reggie Bradford Webcast On Demand WebCenter in Action Series: Qualcomm Provides a Seamless Experience for Customers with Oracle WebCenter, presented by Qualcomm and Keste. Webcast On Demand Social Business Thought Leaders Series: 6 Counterintuitive Best Practices for Social Collaboration Adoption, featuring John Brunswick, Oracle. Webcast On Demand Oracle WebCenter Connects Patients and Researchers in Cancer Control Mission, presented by Canadian Partnership Against Cancer and App-Systems Webcast On Demand Oracle WebCenter: Modernize, Aggregate and Extend Your Portals Webcast On Demand Top 10 Technology Trends Driving Business Innovation, featuring Andy Mulholland, CTO, Capgemini Webcast On Demand Ancestry.com Helps Families Uncover History with Oracl e WebCenter Webcast On Demand Organic Business Networks: Doing Business in a Hyper-Connected World, featuring Mike Fauscette, GVP, IDC Webcast On Demand Social Business and Innovation, featuring John Mancini, President, AIIM Webcast On Demand Do More with Oracle WebCenter: Expand Beyond Web Experience Management Webcast On Demand Race Against the Machine, featuring Andrew McAfee, author and principal scientist at MIT Webcast On Demand Introducing Oracle WebCenter Sites 11gR1: Transforming the Online Experience Webcast On Demand Mobile is the New Face of Engagement, featuring Ted Schadler, Vice President & Principal Analyst, Forrester Research Inc Webcast Analyst Report: IDC Research: Oracle Debuts New Release of Oracle WebCenter Sites.

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  • Systems of Engagement

    - by Michael Snow
    12.00 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-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}  Engagement Week 12.00 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-family:"Calibri","sans-serif"; mso-ascii- mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi- mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} This week we’ll be looking at the ever evolving topic of systems of engagement. This topic continues generating widespread discussion around how we connect with businesses, employers, governments, and extended social communities across multiple channels spanning web, mobile and human face to face contact. Earlier in our Social Business Thought Leader Webcast Series, we had AIIM President John Mancini presenting "Moving from Records to Engagement to Insight" discussing the factors that are driving organizations to think more strategically about the intersection of content management, social technologies, and business processes. John spoke about how Content Management and Enterprise IT are being changed by social technologies and how new technologies are being used to drive innovation and transform processes along and what the implications of this transformation are for information professionals. He used these two slides below to illustrate the evolution from Systems of Record to Systems of Engagement. The AIIM White Paper is available for download from the AIIM website. Later this week (09/20), we'll have another session in our Social Business Thought Leader Webcast Series featuring  R “Ray” Wang (@rwang0) Principal Analyst & CEO from Constellation Research presenting: "Engaging Customers in the Era of Overexposure"  More info to come tomorrow on the upcoming webcast this week. ~~~~~~ In the spirit of spreading good karma - one of the first things that came to mind as I was thinking about "Engagement" was the evolution of the Marriage Proposal.  Someone sent me a link to this link a couple of months ago and it raises the bar on all proposals. I hope you'll enjoy!

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  • Deploying ASP.NET MVC to IIS6: pages are just blank

    - by BryanGrimes
    I have an MVC app that is actually on a couple other servers but I didn't do the deploy. For this deploy I have added the wildcard to aspnet_isapi.dll which has gotten rid of the 404 error. But the pages are not pulling up, rather everything is just blank. I can't seem to find any IIS configuration differences. The Global asax.cs file does have routing defined, but as I've seen on a working server, that file isn't just hanging out in the root or anything so obvious. What could I be missing here? All of the servers are running IIS6 and I have compared the setups and they look the same to me at this point. Thanks... Bryan EDIT for the comments thus far: I've looked in the event logs with no luck, and scoured various IIS logs per David Wang: blogs.msdn.com. Below is the Global.asax.cs file... public class MvcApplication : System.Web.HttpApplication { public static void RegisterRoutes(RouteCollection routes) { routes.IgnoreRoute("{resource}.axd/{*pathInfo}"); routes.IgnoreRoute("error.axd"); // for Elmah // For deployment to IIS6 routes.Add(new Route ( "{controller}.mvc/{action}/{id}", new RouteValueDictionary(new { action = "Index", id = (string)null }), new MvcRouteHandler() )); routes.MapRoute( "WeeklyTimeSave", "Time/Save", new { controller = "Time", action = "Save" } ); routes.MapRoute( "WeeklyTimeAdd", "Time/Add", new { controller = "Time", action = "Add" } ); routes.MapRoute( "WeeklyTimeEdit", "Time/Edit/{id}", new { controller = "Time", action = "Edit", id = "" } ); routes.MapRoute( "FromSalesforce", "Home/{id}", new { controller = "Home", action = "Index", id = "" }); routes.MapRoute( "Default2", "{controller}/{id}", new { controller = "Home", action = "Index", id = "" } ); routes.MapRoute( "Default", "{controller}/{action}/{id}", new { controller = "Home", action = "Index", id = "" } ); } protected void Application_Start() { RegisterRoutes(RouteTable.Routes); } } Maybe this is as stupid as the asax file not being somewhere it needs to be, but heck if I know at this point.

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  • propositional theorems

    - by gcc
    wang's theorem to prove theorems in propositonal calculus Label Sequent Comment S1: P ? Q, Q ? R, ¬R ? ¬P Initial sequent. S2: ¬P ? Q, ¬Q ? R, ¬R ? ¬P Two applications of R5. S3: ¬P ? Q, ¬Q ? R ? ¬P, R Rl. S4: ¬P, ¬Q ? R ? ¬P, R S4 and S5 are obtained from S3 with R3. Note that S4 is an axiom since P appears on both sides of the sequent ar- row at the top level. S5: Q, ¬Q ? R ? ¬P, R The other sequent generated by the ap- plication of R3. S6: Q, ¬Q ? ¬P, R S6 and S7 are obtained from S5 using R3. S7: Q, R ? ¬P, R This is an axiom. S8: Q ? ¬P, R, Q Obtained from S6 using R1. S8 is an axiom. The original sequent is now proved, since it has successfully been transformed into a set of three axioms with no unproved sequents left over. //R1,R2,R3,R4,R5 is transformation myhomework is so complicate as you can see and i must finish homework in 4 days i just want help ,can you show me how i should construct the algorithm or how i should take and store the input

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  • String Manipulation in C

    - by baris_a
    Hi guys, I am helping my nephew for his C lab homework, it is a string manipulation assignment and applying Wang's algorithm. Here is the BNF representation for the input. <sequent> ::= <lhs> # <rhs> <lhs> ::= <formulalist>| e <rhs> ::= <formulalist>| e <formulalist> ::= <formula>|<formula> , <formulalist> <formula> ::= <letter>| - <formula>| (<formula><in?xop><formula>) <in?xop> ::= & | | | > <letter> ::= A | B | ... | Z What is the best practice to handle and parse this kind of input in C? How can I parse this structure without using struct? Thanks in advance.

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  • Body Mass Index program in haskell

    - by user364996
    Hi there. I'm trying to write a simple program in Haskell that can determine someone's body mass index. Here's what I have written: type Height = Float type Weight = Float type PeopleStats = [(String, Height, Weight)] and... bmi :: Height -> Weight -> Float bmi heightCm weightKg = weightKg/(heightCm)^2 healthy :: Height -> Weight -> Bool healthy heightCm weightKg | 25 > index && 18 < index = True | otherwise = False where index = bmi heightCm weightKg So far, the function "healthy" can calculate someone's BMI, and the function "healthyPeople" returns a boolean statement determining if the person's BMI falls within the limits which is considered normal for a healthy person. I want to write a function called "healthyPeople". healthyPeople :: PeopleStats -> [String] This function needs to take a list of PeopleStats and returns a list of names (Strings) of people who are deemed to be "healthy" from the "healthy" function. For example: If I input [("Lee", 65, 185), ("Wang", 170, 100), ("Tsu", 160, 120)] I will get a list of the names of the people whose BMI returns true form the boolean function in "healthy". Please help !!!!

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  • CDN on Hosted Service in Windows Azure

    - by Shaun
    Yesterday I told Wang Tao, an annoying colleague sitting beside me, about how to make the static content enable the CDN in his website which had just been published on Windows Azure. The approach would be Move the static content, the images, CSS files, etc. into the blob storage. Enable the CDN on his storage account. Change the URL of those static files to the CDN URL. I think these are the very common steps when using CDN. But this morning I found that the new Windows Azure SDK 1.4 and new Windows Azure Developer Portal had just been published announced at the Windows Azure Blog. One of the new features in this release is about the CDN, which means we can enabled the CDN not only for a storage account, but a hosted service as well. Within this new feature the steps I mentioned above would be turned simpler a lot.   Enable CDN for Hosted Service To enable the CDN for a hosted service we just need to log on the Windows Azure Developer Portal. Under the “Hosted Services, Storage Accounts & CDN” item we will find a new menu on the left hand side said “CDN”, where we can manage the CDN for storage account and hosted service. As we can see the hosted services and storage accounts are all listed in my subscriptions. To enable a CDN for a hosted service is veru simple, just select a hosted service and click the New Endpoint button on top. In this dialog we can select the subscription and the storage account, or the hosted service we want the CDN to be enabled. If we selected the hosted service, like I did in the image above, the “Source URL for the CDN endpoint” will be shown automatically. This means the windows azure platform will make all contents under the “/cdn” folder as CDN enabled. But we cannot change the value at the moment. The following 3 checkboxes next to the URL are: Enable CDN: Enable or disable the CDN. HTTPS: If we need to use HTTPS connections check it. Query String: If we are caching content from a hosted service and we are using query strings to specify the content to be retrieved, check it. Just click the “Create” button to let the windows azure create the CDN for our hosted service. The CDN would be available within 60 minutes as Microsoft mentioned. My experience is that about 15 minutes the CDN could be used and we can find the CDN URL in the portal as well.   Put the Content in CDN in Hosted Service Let’s create a simple windows azure project in Visual Studio with a MVC 2 Web Role. When we created the CDN mentioned above the source URL of CDN endpoint would be under the “/cdn” folder. So in the Visual Studio we create a folder under the website named “cdn” and put some static files there. Then all these files would be cached by CDN if we use the CDN endpoint. The CDN of the hosted service can cache some kind of “dynamic” result with the Query String feature enabled. We create a controller named CdnController and a GetNumber action in it. The routed URL of this controller would be /Cdn/GetNumber which can be CDN-ed as well since the URL said it’s under the “/cdn” folder. In the GetNumber action we just put a number value which specified by parameter into the view model, then the URL could be like /Cdn/GetNumber?number=2. 1: using System; 2: using System.Collections.Generic; 3: using System.Linq; 4: using System.Web; 5: using System.Web.Mvc; 6:  7: namespace MvcWebRole1.Controllers 8: { 9: public class CdnController : Controller 10: { 11: // 12: // GET: /Cdn/ 13:  14: public ActionResult GetNumber(int number) 15: { 16: return View(number); 17: } 18:  19: } 20: } And we add a view to display the number which is super simple. 1: <%@ Page Title="" Language="C#" MasterPageFile="~/Views/Shared/Site.Master" Inherits="System.Web.Mvc.ViewPage<int>" %> 2:  3: <asp:Content ID="Content1" ContentPlaceHolderID="TitleContent" runat="server"> 4: GetNumber 5: </asp:Content> 6:  7: <asp:Content ID="Content2" ContentPlaceHolderID="MainContent" runat="server"> 8:  9: <h2>The number is: <% 1: : Model.ToString() %></h2> 10:  11: </asp:Content> Since this action is under the CdnController the URL would be under the “/cdn” folder which means it can be CDN-ed. And since we checked the “Query String” the content of this dynamic page will be cached by its query string. So if I use the CDN URL, http://az25311.vo.msecnd.net/GetNumber?number=2, the CDN will firstly check if there’s any content cached with the key “GetNumber?number=2”. If yes then the CDN will return the content directly; otherwise it will connect to the hosted service, http://aurora-sys.cloudapp.net/Cdn/GetNumber?number=2, and then send the result back to the browser and cached in CDN. But to be notice that the query string are treated as string when used by the key of CDN element. This means the URLs below would be cached in 2 elements in CDN: http://az25311.vo.msecnd.net/GetNumber?number=2&page=1 http://az25311.vo.msecnd.net/GetNumber?page=1&number=2 The final step is to upload the project onto azure. Test the Hosted Service CDN After published the project on azure, we can use the CDN in the website. The CDN endpoint we had created is az25311.vo.msecnd.net so all files under the “/cdn” folder can be requested with it. Let’s have a try on the sample.htm and c_great_wall.jpg static files. Also we can request the dynamic page GetNumber with the query string with the CDN endpoint. And if we refresh this page it will be shown very quickly since the content comes from the CDN without MCV server side process. We style of this page was missing. This is because the CSS file was not includes in the “/cdn” folder so the page cannot retrieve the CSS file from the CDN URL.   Summary In this post I introduced the new feature in Windows Azure CDN with the release of Windows Azure SDK 1.4 and new Developer Portal. With the CDN of the Hosted Service we can just put the static resources under a “/cdn” folder so that the CDN can cache them automatically and no need to put then into the blob storage. Also it support caching the dynamic content with the Query String feature. So that we can cache some parts of the web page by using the UserController and CDN. For example we can cache the log on user control in the master page so that the log on part will be loaded super-fast. There are some other new features within this release you can find here. And for more detailed information about the Windows Azure CDN please have a look here as well.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • A New Threat To Web Applications: Connection String Parameter Pollution (CSPP)

    - by eric.maurice
    Hi, this is Shaomin Wang. I am a security analyst in Oracle's Security Alerts Group. My primary responsibility is to evaluate the security vulnerabilities reported externally by security researchers on Oracle Fusion Middleware and to ensure timely resolution through the Critical Patch Update. Today, I am going to talk about a serious type of attack: Connection String Parameter Pollution (CSPP). Earlier this year, at the Black Hat DC 2010 Conference, two Spanish security researchers, Jose Palazon and Chema Alonso, unveiled a new class of security vulnerabilities, which target insecure dynamic connections between web applications and databases. The attack called Connection String Parameter Pollution (CSPP) exploits specifically the semicolon delimited database connection strings that are constructed dynamically based on the user inputs from web applications. CSPP, if carried out successfully, can be used to steal user identities and hijack web credentials. CSPP is a high risk attack because of the relative ease with which it can be carried out (low access complexity) and the potential results it can have (high impact). In today's blog, we are going to first look at what connection strings are and then review the different ways connection string injections can be leveraged by malicious hackers. We will then discuss how CSPP differs from traditional connection string injection, and the measures organizations can take to prevent this kind of attacks. In web applications, a connection string is a set of values that specifies information to connect to backend data repositories, in most cases, databases. The connection string is passed to a provider or driver to initiate a connection. Vendors or manufacturers write their own providers for different databases. Since there are many different providers and each provider has multiple ways to make a connection, there are many different ways to write a connection string. Here are some examples of connection strings from Oracle Data Provider for .Net/ODP.Net: Oracle Data Provider for .Net / ODP.Net; Manufacturer: Oracle; Type: .NET Framework Class Library: - Using TNS Data Source = orcl; User ID = myUsername; Password = myPassword; - Using integrated security Data Source = orcl; Integrated Security = SSPI; - Using the Easy Connect Naming Method Data Source = username/password@//myserver:1521/my.server.com - Specifying Pooling parameters Data Source=myOracleDB; User Id=myUsername; Password=myPassword; Min Pool Size=10; Connection Lifetime=120; Connection Timeout=60; Incr Pool Size=5; Decr Pool Size=2; There are many variations of the connection strings, but the majority of connection strings are key value pairs delimited by semicolons. Attacks on connection strings are not new (see for example, this SANS White Paper on Securing SQL Connection String). Connection strings are vulnerable to injection attacks when dynamic string concatenation is used to build connection strings based on user input. When the user input is not validated or filtered, and malicious text or characters are not properly escaped, an attacker can potentially access sensitive data or resources. For a number of years now, vendors, including Oracle, have created connection string builder class tools to help developers generate valid connection strings and potentially prevent this kind of vulnerability. Unfortunately, not all application developers use these utilities because they are not aware of the danger posed by this kind of attacks. So how are Connection String parameter Pollution (CSPP) attacks different from traditional Connection String Injection attacks? First, let's look at what parameter pollution attacks are. Parameter pollution is a technique, which typically involves appending repeating parameters to the request strings to attack the receiving end. Much of the public attention around parameter pollution was initiated as a result of a presentation on HTTP Parameter Pollution attacks by Stefano Di Paola and Luca Carettoni delivered at the 2009 Appsec OWASP Conference in Poland. In HTTP Parameter Pollution attacks, an attacker submits additional parameters in HTTP GET/POST to a web application, and if these parameters have the same name as an existing parameter, the web application may react in different ways depends on how the web application and web server deal with multiple parameters with the same name. When applied to connections strings, the rule for the majority of database providers is the "last one wins" algorithm. If a KEYWORD=VALUE pair occurs more than once in the connection string, the value associated with the LAST occurrence is used. This opens the door to some serious attacks. By way of example, in a web application, a user enters username and password; a subsequent connection string is generated to connect to the back end database. Data Source = myDataSource; Initial Catalog = db; Integrated Security = no; User ID = myUsername; Password = XXX; In the password field, if the attacker enters "xxx; Integrated Security = true", the connection string becomes, Data Source = myDataSource; Initial Catalog = db; Integrated Security = no; User ID = myUsername; Password = XXX; Intergrated Security = true; Under the "last one wins" principle, the web application will then try to connect to the database using the operating system account under which the application is running to bypass normal authentication. CSPP poses serious risks for unprepared organizations. It can be particularly dangerous if an Enterprise Systems Management web front-end is compromised, because attackers can then gain access to control panels to configure databases, systems accounts, etc. Fortunately, organizations can take steps to prevent this kind of attacks. CSPP falls into the Injection category of attacks like Cross Site Scripting or SQL Injection, which are made possible when inputs from users are not properly escaped or sanitized. Escaping is a technique used to ensure that characters (mostly from user inputs) are treated as data, not as characters, that is relevant to the interpreter's parser. Software developers need to become aware of the danger of these attacks and learn about the defenses mechanism they need to introduce in their code. As well, software vendors need to provide templates or classes to facilitate coding and eliminate developers' guesswork for protecting against such vulnerabilities. Oracle has introduced the OracleConnectionStringBuilder class in Oracle Data Provider for .NET. Using this class, developers can employ a configuration file to provide the connection string and/or dynamically set the values through key/value pairs. It makes creating connection strings less error-prone and easier to manager, and ultimately using the OracleConnectionStringBuilder class provides better security against injection into connection strings. For More Information: - The OracleConnectionStringBuilder is located at http://download.oracle.com/docs/cd/B28359_01/win.111/b28375/OracleConnectionStringBuilderClass.htm - Oracle has developed a publicly available course on preventing SQL Injections. The Server Technologies Curriculum course "Defending Against SQL Injection Attacks!" is located at http://st-curriculum.oracle.com/tutorial/SQLInjection/index.htm - The OWASP web site also provides a number of useful resources. It is located at http://www.owasp.org/index.php/Main_Page

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  • Node.js Adventure - Node.js on Windows

    - by Shaun
    Two weeks ago I had had a talk with Wang Tao, a C# MVP in China who is currently running his startup company and product named worktile. He asked me to figure out a synchronization solution which helps his product in the future. And he preferred me implementing the service in Node.js, since his worktile is written in Node.js. Even though I have some experience in ASP.NET MVC, HTML, CSS and JavaScript, I don’t think I’m an expert of JavaScript. In fact I’m very new to it. So it scared me a bit when he asked me to use Node.js. But after about one week investigate I have to say Node.js is very easy to learn, use and deploy, even if you have very limited JavaScript skill. And I think I became love Node.js. Hence I decided to have a series named “Node.js Adventure”, where I will demonstrate my story of learning and using Node.js in Windows and Windows Azure. And this is the first one.   (Brief) Introduction of Node.js I don’t want to have a fully detailed introduction of Node.js. There are many resource on the internet we can find. But the best one is its homepage. Node.js was created by Ryan Dahl, sponsored by Joyent. It’s consist of about 80% C/C++ for core and 20% JavaScript for API. It utilizes CommonJS as the module system which we will explain later. The official definition of Node.js is Node.js is a platform built on Chrome's JavaScript runtime for easily building fast, scalable network applications. Node.js uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, perfect for data-intensive real-time applications that run across distributed devices. First of all, Node.js utilizes JavaScript as its development language and runs on top of V8 engine, which is being used by Chrome. It brings JavaScript, a client-side language into the backend service world. So many people said, even though not that actually, “Node.js is a server side JavaScript”. Additionally, Node.js uses an event-driven, non-blocking IO model. This means in Node.js there’s no way to block currently working thread. Every operation in Node.js executed asynchronously. This is a huge benefit especially if our code needs IO operations such as reading disks, connect to database, consuming web service, etc.. Unlike IIS or Apache, Node.js doesn’t utilize the multi-thread model. In Node.js there’s only one working thread serves all users requests and resources response, as the ST star in the figure below. And there is a POSIX async threads pool in Node.js which contains many async threads (AT stars) for IO operations. When a user have an IO request, the ST serves it but it will not do the IO operation. Instead the ST will go to the POSIX async threads pool to pick up an AT, pass this operation to it, and then back to serve any other requests. The AT will actually do the IO operation asynchronously. Assuming before the AT complete the IO operation there is another user comes. The ST will serve this new user request, pick up another AT from the POSIX and then back. If the previous AT finished the IO operation it will take the result back and wait for the ST to serve. ST will take the response and return the AT to POSIX, and then response to the user. And if the second AT finished its job, the ST will response back to the second user in the same way. As you can see, in Node.js there’s only one thread serve clients’ requests and POSIX results. This thread looping between the users and POSIX and pass the data back and forth. The async jobs will be handled by POSIX. This is the event-driven non-blocking IO model. The performance of is model is much better than the multi-threaded blocking model. For example, Apache is built in multi-threaded blocking model while Nginx is in event-driven non-blocking mode. Below is the performance comparison between them. And below is the memory usage comparison between them. These charts are captured from the video NodeJS Basics: An Introductory Training, which presented at Cloud Foundry Developer Advocate.   Node.js on Windows To execute Node.js application on windows is very simple. First of you we need to download the latest Node.js platform from its website. After installed, it will register its folder into system path variant so that we can execute Node.js at anywhere. To confirm the Node.js installation, just open up a command windows and type “node”, then it will show the Node.js console. As you can see this is a JavaScript interactive console. We can type some simple JavaScript code and command here. To run a Node.js JavaScript application, just specify the source code file name as the argument of the “node” command. For example, let’s create a Node.js source code file named “helloworld.js”. Then copy a sample code from Node.js website. 1: var http = require("http"); 2:  3: http.createServer(function (req, res) { 4: res.writeHead(200, {"Content-Type": "text/plain"}); 5: res.end("Hello World\n"); 6: }).listen(1337, "127.0.0.1"); 7:  8: console.log("Server running at http://127.0.0.1:1337/"); This code will create a web server, listening on 1337 port and return “Hello World” when any requests come. Run it in the command windows. Then open a browser and navigate to http://localhost:1337/. As you can see, when using Node.js we are not creating a web application. In fact we are likely creating a web server. We need to deal with request, response and the related headers, status code, etc.. And this is one of the benefit of using Node.js, lightweight and straightforward. But creating a website from scratch again and again is not acceptable. The good news is that, Node.js utilizes CommonJS as its module system, so that we can leverage some modules to simplify our job. And furthermore, there are about ten thousand of modules available n the internet, which covers almost all areas in server side application development.   NPM and Node.js Modules Node.js utilizes CommonJS as its module system. A module is a set of JavaScript files. In Node.js if we have an entry file named “index.js”, then all modules it needs will be located at the “node_modules” folder. And in the “index.js” we can import modules by specifying the module name. For example, in the code we’ve just created, we imported a module named “http”, which is a build-in module installed alone with Node.js. So that we can use the code in this “http” module. Besides the build-in modules there are many modules available at the NPM website. Thousands of developers are contributing and downloading modules at this website. Hence this is another benefit of using Node.js. There are many modules we can use, and the numbers of modules increased very fast, and also we can publish our modules to the community. When I wrote this post, there are totally 14,608 modules at NPN and about 10 thousand downloads per day. Install a module is very simple. Let’s back to our command windows and input the command “npm install express”. This command will install a module named “express”, which is a MVC framework on top of Node.js. And let’s create another JavaScript file named “helloweb.js” and copy the code below in it. I imported the “express” module. And then when the user browse the home page it will response a text. If the incoming URL matches “/Echo/:value” which the “value” is what the user specified, it will pass it back with the current date time in JSON format. And finally my website was listening at 12345 port. 1: var express = require("express"); 2: var app = express(); 3:  4: app.get("/", function(req, res) { 5: res.send("Hello Node.js and Express."); 6: }); 7:  8: app.get("/Echo/:value", function(req, res) { 9: var value = req.params.value; 10: res.json({ 11: "Value" : value, 12: "Time" : new Date() 13: }); 14: }); 15:  16: console.log("Web application opened."); 17: app.listen(12345); For more information and API about the “express”, please have a look here. Start our application from the command window by command “node helloweb.js”, and then navigate to the home page we can see the response in the browser. And if we go to, for example http://localhost:12345/Echo/Hello Shaun, we can see the JSON result. The “express” module is very populate in NPM. It makes the job simple when we need to build a MVC website. There are many modules very useful in NPM. - underscore: A utility module covers many common functionalities such as for each, map, reduce, select, etc.. - request: A very simple HTT request client. - async: Library for coordinate async operations. - wind: Library which enable us to control flow with plain JavaScript for asynchronous programming (and more) without additional pre-compiling steps.   Node.js and IIS I demonstrated how to run the Node.js application from console. Since we are in Windows another common requirement would be, “can I host Node.js in IIS?” The answer is “Yes”. Tomasz Janczuk created a project IISNode at his GitHub space we can find here. And Scott Hanselman had published a blog post introduced about it.   Summary In this post I provided a very brief introduction of Node.js, includes it official definition, architecture and how it implement the event-driven non-blocking model. And then I described how to install and run a Node.js application on windows console. I also described the Node.js module system and NPM command. At the end I referred some links about IISNode, an IIS extension that allows Node.js application runs on IIS. Node.js became a very popular server side application platform especially in this year. By leveraging its non-blocking IO model and async feature it’s very useful for us to build a highly scalable, asynchronously service. I think Node.js will be used widely in the cloud application development in the near future.   In the next post I will explain how to use SQL Server from Node.js.   Hope this helps, Shaun All documents and related graphics, codes are provided "AS IS" without warranty of any kind. Copyright © Shaun Ziyan Xu. This work is licensed under the Creative Commons License.

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  • CSS Dropdown Menu issues

    - by Simon Hume
    Can anyone help with a small problem. I've got a nice simple CSS dropdown menu http://www.cinderellahair.co.uk/new/CSSDropdown.html The problem I have is when you rollover a menu item that has children which are wider than the content, it pushes the whole menu right. Aside of shortening the child menu links down, is there any tweak I can make to my CSS to stop this happening? CSS Code: /* General */ #cssdropdown, #cssdropdown ul { list-style: none; } #cssdropdown, #cssdropdown * { padding: 0; margin: 0; } #cssdropdown {padding:43px 0px 0px 0px;} /* Head links */ #cssdropdown li.headlink { margin:0px 40px 0px -1px; float: left; background-color: #e9e9e9;} #cssdropdown li.headlink a { display: block; padding: 0px 0px 0px 5px; text-decoration:none; } #cssdropdown li.headlink a:hover { text-decoration:underline; } /* Child lists and links */ #cssdropdown li.headlink ul { display: none; text-align: left; padding:10px 0px 0px 0px; font-size:12px; float:left;} #cssdropdown li.headlink:hover ul { display: block; } #cssdropdown li.headlink ul li a { padding: 5px; height: 17px; } #cssdropdown li.headlink ul li a:hover { background-color: #333; } /* Pretty styling */ body { font-family:Georgia, "Times New Roman", Times, serif; font-size: 16px; } #cssdropdown a { color: grey; } #cssdropdown ul li a:hover { text-decoration: none; } #cssdropdown li.headlink { background-color: white; } #cssdropdown li.headlink ul { padding-bottom: 10px;} HTML: <ul id="cssdropdown"> <li class="headlink"><a href="http://www.cinderellahair.co.uk/new/index.php">HOME</a></li> <li class="headlink"><a href="http://www.cinderellahair.co.uk/new/gallery/gallery.php">GALLERY</a> <ul> <li><a href="http://amazon.com/">CELEBRITY</a></li> <li><a href="http://ebay.com/">BEFORE &amp; AFTER</a></li> <li><a href="http://craigslist.com/">HAIR TYPES</a></li> </ul> </li> <li class="headlink"><a href="http://www.cinderellahair.co.uk/new/about-cinderella-hair-extensions/about-us.php">ABOUT US</a> <ul> <li><a href="http://amazon.com/">WHY CHOOSE CINDERELLA</a></li> <li><a href="http://ebay.com/">TESTIMONIALS</a></li> <li><a href="http://craigslist.com/">MINI VIDEO CLIPS</a></li> <li><a href="http://craigslist.com/">OUR HAIR PRODUCTS</a></li> </ul> </li> <li class="headlink"><a href="http://www.cinderellahair.co.uk/new/news-and-offers/news.php">NEWS &amp; OFFERS</a> <ul> <li><a href="http://amazon.com/">VERA WANG FREE GIVEAWAY</a></li> <li><a href="http://ebay.com/">CINDERELLA ON TV</a></li> <li><a href="http://craigslist.com/">CINDERELLA IN THE PRESS</a></li> <li><a href="http://craigslist.com/">CINDRELLA NEWSLETTERS</a></li> </ul> </li> <li class="headlink"><a href="http://www.cinderellahair.co.uk/new/cinderella-salon/salon-finder.php">SALON FINDER</a></li> </ul> JS Code: $(document).ready(function(){ $('#cssdropdown li.headlink').hover( function() { $('ul', this).css('display', 'block'); }, function() { $('ul', this).css('display', 'none'); }); }); Full code is on the link above, just view source.

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  • Passing a comparator syntax help in Java

    - by Crystal
    I've tried this a couple ways, the first is have a class that implements comparator at the bottom of the following code. When I try to pass the comparat in sortListByLastName, I get a constructor not found error and I am not sure why import java.util.*; public class OrganizeThis implements WhoDoneIt { /** Add a person to the organizer @param p A person object */ public void add(Person p) { staff.put(p.getEmail(), p); //System.out.println("Person " + p + "added"); } /** * Remove a Person from the organizer. * * @param email The email of the person to be removed. */ public void remove(String email) { staff.remove(email); } /** * Remove all contacts from the organizer. * */ public void empty() { staff.clear(); } /** * Find the person stored in the organizer with the email address. * Note, each person will have a unique email address. * * @param email The person email address you are looking for. * */ public Person findByEmail(String email) { Person aPerson = staff.get(email); return aPerson; } /** * Find all persons stored in the organizer with the same last name. * Note, there can be multiple persons with the same last name. * * @param lastName The last name of the persons your are looking for. * */ public Person[] find(String lastName) { ArrayList<Person> names = new ArrayList<Person>(); for (Person s : staff.values()) { if (s.getLastName() == lastName) { names.add(s); } } // Convert ArrayList back to Array Person nameArray[] = new Person[names.size()]; names.toArray(nameArray); return nameArray; } /** * Return all the contact from the orgnizer in * an array sorted by last name. * * @return An array of Person objects. * */ public Person[] getSortedListByLastName() { PersonLastNameComparator comp = new PersonLastNameComparator(); Map<String, Person> sorted = new TreeMap<String, Person>(comp); ArrayList<Person> sortedArrayList = new ArrayList<Person>(); for (Person s: sorted.values()) { sortedArrayList.add(s); } Person sortedArray[] = new Person[sortedArrayList.size()]; sortedArrayList.toArray(sortedArray); return sortedArray; } private Map<String, Person> staff = new HashMap<String, Person>(); public static void main(String[] args) { OrganizeThis testObj = new OrganizeThis(); Person person1 = new Person("J", "W", "111-222-3333", "[email protected]"); Person person2 = new Person("K", "W", "345-678-9999", "[email protected]"); Person person3 = new Person("Phoebe", "Wang", "322-111-3333", "[email protected]"); Person person4 = new Person("Nermal", "Johnson", "322-342-5555", "[email protected]"); Person person5 = new Person("Apple", "Banana", "123-456-1111", "[email protected]"); testObj.add(person1); testObj.add(person2); testObj.add(person3); testObj.add(person4); testObj.add(person5); System.out.println(testObj.findByEmail("[email protected]")); System.out.println("------------" + '\n'); Person a[] = testObj.find("W"); for (Person p : a) System.out.println(p); System.out.println("------------" + '\n'); a = testObj.find("W"); for (Person p : a) System.out.println(p); System.out.println("SORTED" + '\n'); a = testObj.getSortedListByLastName(); for (Person b : a) { System.out.println(b); } System.out.println(testObj.getAuthor()); } } class PersonLastNameComparator implements Comparator<Person> { public int compare(Person a, Person b) { return a.getLastName().compareTo(b.getLastName()); } } And then when I tried doing it by creating an anonymous inner class, I also get a constructor TreeMap cannot find symbol error. Any thoughts? inner class method: public Person[] getSortedListByLastName() { //PersonLastNameComparator comp = new PersonLastNameComparator(); Map<String, Person> sorted = new TreeMap<String, Person>(new Comparator<Person>() { public int compare(Person a, Person b) { return a.getLastName().compareTo(b.getLastName()); } }); ArrayList<Person> sortedArrayList = new ArrayList<Person>(); for (Person s: sorted.values()) { sortedArrayList.add(s); } Person sortedArray[] = new Person[sortedArrayList.size()]; sortedArrayList.toArray(sortedArray); return sortedArray; }

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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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  • Sorting in Hash Maps in Java

    - by Crystal
    I'm trying to get familiar with Collections. I have a String which is my key, email address, and a Person object (firstName, lastName, telephone, email). I read in the Java collections chapter on Sun's webpages that if you had a HashMap and wanted it sorted, you could use a TreeMap. How does this sort work? Is it based on the compareTo() method you have in your Person class? I overrode the compareTo() method in my Person class to sort by lastName. But it isn't working properly and was wondering if I have the right idea or not. getSortedListByLastName at the bottom of this code is where I try to convert to a TreeMap. Also, if this is the correct way to do it, or one of the correct ways to do it, how do I then sort by firstName since my compareTo() is comparing by lastName. import java.util.*; public class OrganizeThis { /** Add a person to the organizer @param p A person object */ public void add(Person p) { staff.put(p.getEmail(), p); //System.out.println("Person " + p + "added"); } /** * Remove a Person from the organizer. * * @param email The email of the person to be removed. */ public void remove(String email) { staff.remove(email); } /** * Remove all contacts from the organizer. * */ public void empty() { staff.clear(); } /** * Find the person stored in the organizer with the email address. * Note, each person will have a unique email address. * * @param email The person email address you are looking for. * */ public Person findByEmail(String email) { Person aPerson = staff.get(email); return aPerson; } /** * Find all persons stored in the organizer with the same last name. * Note, there can be multiple persons with the same last name. * * @param lastName The last name of the persons your are looking for. * */ public Person[] find(String lastName) { ArrayList<Person> names = new ArrayList<Person>(); for (Person s : staff.values()) { if (s.getLastName() == lastName) { names.add(s); } } // Convert ArrayList back to Array Person nameArray[] = new Person[names.size()]; names.toArray(nameArray); return nameArray; } /** * Return all the contact from the orgnizer in * an array sorted by last name. * * @return An array of Person objects. * */ public Person[] getSortedListByLastName() { Map<String, Person> sorted = new TreeMap<String, Person>(staff); ArrayList<Person> sortedArrayList = new ArrayList<Person>(); for (Person s: sorted.values()) { sortedArrayList.add(s); } Person sortedArray[] = new Person[sortedArrayList.size()]; sortedArrayList.toArray(sortedArray); return sortedArray; } private Map<String, Person> staff = new HashMap<String, Person>(); public static void main(String[] args) { OrganizeThis testObj = new OrganizeThis(); Person person1 = new Person("J", "W", "111-222-3333", "[email protected]"); Person person2 = new Person("K", "W", "345-678-9999", "[email protected]"); Person person3 = new Person("Phoebe", "Wang", "322-111-3333", "[email protected]"); Person person4 = new Person("Nermal", "Johnson", "322-342-5555", "[email protected]"); Person person5 = new Person("Apple", "Banana", "123-456-1111", "[email protected]"); testObj.add(person1); testObj.add(person2); testObj.add(person3); testObj.add(person4); testObj.add(person5); System.out.println(testObj.findByEmail("[email protected]")); System.out.println("------------" + '\n'); Person a[] = testObj.find("W"); for (Person p : a) System.out.println(p); System.out.println("------------" + '\n'); a = testObj.find("W"); for (Person p : a) System.out.println(p); System.out.println("SORTED" + '\n'); a = testObj.getSortedListByLastName(); for (Person b : a) { System.out.println(b); } } } Person class: public class Person implements Comparable { String firstName; String lastName; String telephone; String email; public Person() { firstName = ""; lastName = ""; telephone = ""; email = ""; } public Person(String firstName) { this.firstName = firstName; } public Person(String firstName, String lastName, String telephone, String email) { this.firstName = firstName; this.lastName = lastName; this.telephone = telephone; this.email = email; } public String getFirstName() { return firstName; } public void setFirstName(String firstName) { this.firstName = firstName; } public String getLastName() { return lastName; } public void setLastName(String lastName) { this.lastName = lastName; } public String getTelephone() { return telephone; } public void setTelephone(String telephone) { this.telephone = telephone; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; } public int compareTo(Object o) { String s1 = this.lastName + this.firstName; String s2 = ((Person) o).lastName + ((Person) o).firstName; return s1.compareTo(s2); } public boolean equals(Object otherObject) { // a quick test to see if the objects are identical if (this == otherObject) { return true; } // must return false if the explicit parameter is null if (otherObject == null) { return false; } if (!(otherObject instanceof Person)) { return false; } Person other = (Person) otherObject; return firstName.equals(other.firstName) && lastName.equals(other.lastName) && telephone.equals(other.telephone) && email.equals(other.email); } public int hashCode() { return this.email.toLowerCase().hashCode(); } public String toString() { return getClass().getName() + "[firstName = " + firstName + '\n' + "lastName = " + lastName + '\n' + "telephone = " + telephone + '\n' + "email = " + email + "]"; } }

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