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  • The Product Owner

    - by Robert May
    In a previous post, I outlined the rules of Scrum.  This post details one of those rules. Picking a most important part of Scrum is difficult.  All of the rules are required, but if there were one rule that is “more” required that every other rule, its having a good Product Owner.  Simply put, the Product Owner can make or break the project. Duties of the Product Owner A Product Owner has many duties and responsibilities.  I’ll talk about each of these duties in detail below. A Product Owner: Discovers and records stories for the backlog. Prioritizes stories in the Product Backlog, Release Backlog and Iteration Backlog. Determines Release dates and Iteration Dates. Develops story details and helps the team understand those details. Helps QA to develop acceptance tests. Interact with the Customer to make sure that the product is meeting the customer’s needs. Discovers and Records Stories for the Backlog When I do Scrum, I always use User Stories as the means for capturing functionality that’s required in the system.  Some people will use Use Cases, but the same rule applies.  The Product Owner has the ultimate responsibility for figuring out what functionality will be in the system.  Many different mechanisms for capturing this input can be used.  User interviews are great, but all sources should be considered, including talking with Customer Support types.  Often, they hear what users are struggling with the most and are a great source for stories that can make the application easier to use. Care should be taken when soliciting user stories from technical types such as programmers and the people that manage them.  They will almost always give stories that are very technical in nature and may not have a direct benefit for the end user.  Stories are about adding value to the company.  If the stories don’t have direct benefit to the end user, the Product Owner should question whether or not the story should be implemented.  In general, technical stories should be included as tasks in User Stories.  Technical stories are often needed, but the ultimate value to the user is in user based functionality, so technical stories should be considered nothing more than overhead in providing that user functionality. Until the iteration prior to development, stories should be nothing more than short, one line placeholders. An exercise called Story Planning can be used to brainstorm and come up with stories.  I’ll save the description of this activity for another blog post. For more information on User Stories, please read the book User Stories Applied by Mike Cohn. Prioritizes Stories in the Product Backlog, Release Backlog and Iteration Backlog Prioritization of stories is one of the most difficult tasks that a Product Owner must do.  A key concept of Scrum done right is the need to have the team working from a single set of prioritized stories.  If the team does not have a single set of prioritized stories, Scrum will likely fail at your organization.  The Product Owner is the ONLY person who has the responsibility to prioritize that list.  The Product Owner must be very diplomatic and sincerely listen to the people around him so that he can get the priorities correct. Just listening will still not yield the proper priorities.  Care must also be taken to ensure that Return on Investment is also considered.  Ultimately, determining which stories give the most value to the company for the least cost is the most important factor in determining priorities.  Product Owners should be willing to look at cold, hard numbers to determine the order for stories.  Even when many people want a feature, if that features is costly to develop, it may not have as high of a return on investment as features that are cheaper, but not as popular. The act of prioritization often causes conflict in an environment.  Customer Service thinks that feature X is the most important, because it will stop people from calling.  Operations thinks that feature Y is the most important, because it will stop servers from crashing.  Developers think that feature Z is most important because it will make writing software much easier for them.  All of these are useful goals, but the team can have only one list of items, and each item must have a priority that is different from all other stories.  The Product Owner will determine which feature gives the best return on investment and the other features will have to wait their turn, which means that someone will not have their top priority feature implemented first. A weak Product Owner will refuse to do prioritization.  I’ve heard from multiple Product Owners the following phrase, “Well, it’s all got to be done, so what does it matter what order we do it in?”  If your product owner is using this phrase, you need a new Product Owner.  Order is VERY important.  In Scrum, every release is potentially shippable.  If the wrong priority items are developed, then the value added in each release isn’t what it should be.  Additionally, the Product Owner with this mindset doesn’t understand Agile.  A product is NEVER finished, until the company has decided that it is no longer a going concern and they are no longer going to sell the product.  Therefore, prioritization isn’t an event, its something that continues every day.  The logical extension of the phrase “It’s all got to be done” is that you will never ship your product, since a product is never “done.”  Once stories have been prioritized, assigning them to the Release Backlog and the Iteration Backlog becomes relatively simple.  The top priority items are copied into the respective backlogs in order and the task is complete.  The team does have the right to shuffle things around a little in the iteration backlog.  For example, they may determine that working on story C with story A is appropriate because they’re related, even though story B is technically a higher priority than story C.  Or they may decide that story B is too big to complete in the time available after Story A has tasks created, so they’ll work on Story C since it’s smaller.  They can’t, however, go deep into the backlog to pick stories to implement.  The team and the Product Owner should work together to determine what’s best for the company. Prioritization is time consuming, but its one of the most important things a Product Owner does. Determines Release Dates and Iteration Dates Product owners are responsible for determining release dates for a product.  A common misconception that Product Owners have is that every “release” needs to correspond with an actual release to customers.  This is not the case.  In general, releases should be no more than 3 months long.  You  may decide to release the product to the customers, and many companies do release the product to customers, but it may also be an internal release. If a release date is too far away, developers will fall into the trap of not feeling a sense of urgency.  The date is far enough away that they don’t need to give the release their full attention.  Additionally, important tasks, such as performance tuning, regression testing, user documentation, and release preparation, will not happen regularly, making them much more difficult and time consuming to do.  The more frequently you do these tasks, the easier they are to accomplish. The Product Owner will be a key participant in determining whether or not a release should be sent out to the customers.  The determination should be made on whether or not the features contained in the release are valuable enough  and complete enough that the customers will see real value in the release.  Often, some features will take more than three months to get them to a state where they qualify for a release or need additional supporting features to be released.  The product owner has the right to make this determination. In addition to release dates, the Product Owner also will help determine iteration dates.  In general, an iteration length should be chosen and the team should follow that iteration length for an extended period of time.  If the iteration length is changed every iteration, you’re not doing Scrum.  Iteration lengths help the team and company get into a rhythm of developing quality software.  Iterations should be somewhere between 2 and 4 weeks in length.  Any shorter, and significant software will likely not be developed.  Any longer, and the team won’t feel urgency and planning will become very difficult. Iterations may not be extended during the iteration.  Companies where Scrum isn’t really followed will often use this as a strategy to complete all stories.  They don’t want to face the harsh reality of what their true performance is, and looking good is more important than seeking visibility and improving the process and team.  Companies like this typically don’t allow failure.  This is unhealthy.  Failure is part of life and unless we learn from it, we can’t improve.  I would much rather see a team push out stories to the next iteration and then have healthy discussions about why they failed rather than extend the iteration and not deal with the core problems. If iteration length varies, retrospectives become more difficult.  For example, evaluating the performance of the team’s estimation efforts becomes much more difficult if the iteration length varies.  Also, the team must have a velocity measurement.  If the iteration length varies, measuring velocity becomes impossible and upper management no longer will have the ability to evaluate the teams performance.  People external to the team will no longer have the ability to determine when key features are likely to be developed.  Variable iterations cause the entire company to fail and likely cause Scrum to fail at an organization. Develops Story Details and Helps the Team Understand Those Details A key concept in Scrum is that the stories are nothing more than a placeholder for a conversation.  Stories should be nothing more than short, one line statements about the functionality.  The team will then converse with the Product Owner about the details about that story.  The product owner needs to have a very good idea about what the details of the story are and needs to be able to help the team understand those details. Too often, we see this requirement as being translated into the need for comprehensive documentation about the story, including old fashioned requirements documentation.  The team should only develop the documentation that is required and should not develop documentation that is only created because their is a process to do so. In general, what we see that works best is the iteration before a team starts development work on a story, the Product Owner, with other appropriate business analysts, will develop the details of that story.  They’ll figure out what business rules are required, potentially make paper prototypes or other light weight mock-ups, and they seek to understand the story and what is implied.  Note that the time allowed for this task is deliberately short.  The Product Owner only has a single iteration to develop all of the stories for the next iteration. If more than one iteration is used, I’ve found that teams will end up with Big Design Up Front and traditional requirements documents.  This is a waste of time, since the team will need to then have discussions with the Product Owner to figure out what the requirements document says.  Instead of this, skip making the pretty pictures and detailing the nuances of the requirements and build only what is minimally needed by the team to do development.  If something comes up during development, you can address it at that time and figure out what you want to do.  The goal is to keep things as light weight as possible so that everyone can move as quickly as possible. Helps QA to Develop Acceptance Tests In Scrum, no story can be counted until it is accepted by QA.  Because of this, acceptance tests are very important to the team.  In general, acceptance tests need to be developed prior to the iteration or at the very beginning of the iteration so that the team can make sure that the tasks that they develop will fulfill the acceptance criteria. The Product Owner will help the team, including QA, understand what will make the story acceptable.  Note that the Product Owner needs to be careful about specifying that the feature will work “Perfectly” at the end of the iteration.  In general, features are developed a little bit at a time, so only the bit that is being developed should be considered as necessary for acceptance. A weak Product Owner will make statements like “Do it right the first time.”  Not only are these statements damaging to the team (like they would try to do it WRONG the first time . . .), they’re also ignoring the iterative nature of Scrum.  Additionally, a weak product owner will seek to add scope in the acceptance testing.  For example, they will refuse to determine acceptance at the beginning of the iteration, and then, after the team has planned and committed to the iteration, they will expand scope by defining acceptance.  This often causes the team to miss the iteration because scope that wasn’t planned on is included.  There are ways that the team can mitigate this problem.  For example, include extra “Product Owner” time to deal with the uncertainty that you know will be introduced by the Product Owner.  This will slow the perceived velocity of the team and is not ideal, since they’ll be doing more work than they get credit for. Interact with the Customer to Make Sure that the Product is Meeting the Customer’s Needs Once development is complete, what the team has worked on should be put in front of real live people to see if it meets the needs of the customer.  One of the great things about Agile is that if something doesn’t work, we can revisit it in a future iteration!  This frees up the team to make the best decision now and know that if that decision proves to be incorrect, the team can revisit it and change that decision. Features are about adding value to the customer, so if the customer doesn’t find them useful, then having the team make tweaks is valuable.  In general, most software will be 80 to 90 percent “right” after the initial round and only minor tweaks are required.  If proper coding standards are followed, these tweaks are usually minor and easy to accomplish.  Product Owners that are doing a good job will encourage real users to see and use the software, since they know that they are trying to add value to the customer. Poor product owners will think that they know the answers already, that their customers are silly and do stupid things and that they don’t need customer input.  If you have a product owner that is afraid to show the team’s work to real customers, you probably need a different product owner. Up Next, “Who Makes a Good Product Owner.” Followed by, “Messing with the Team.” Technorati Tags: Scrum,Product Owner

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  • MERGE Bug with Filtered Indexes

    - by Paul White
    A MERGE statement can fail, and incorrectly report a unique key violation when: The target table uses a unique filtered index; and No key column of the filtered index is updated; and A column from the filtering condition is updated; and Transient key violations are possible Example Tables Say we have two tables, one that is the target of a MERGE statement, and another that contains updates to be applied to the target.  The target table contains three columns, an integer primary key, a single character alternate key, and a status code column.  A filtered unique index exists on the alternate key, but is only enforced where the status code is ‘a’: CREATE TABLE #Target ( pk integer NOT NULL, ak character(1) NOT NULL, status_code character(1) NOT NULL,   PRIMARY KEY (pk) );   CREATE UNIQUE INDEX uq1 ON #Target (ak) INCLUDE (status_code) WHERE status_code = 'a'; The changes table contains just an integer primary key (to identify the target row to change) and the new status code: CREATE TABLE #Changes ( pk integer NOT NULL, status_code character(1) NOT NULL,   PRIMARY KEY (pk) ); Sample Data The sample data for the example is: INSERT #Target (pk, ak, status_code) VALUES (1, 'A', 'a'), (2, 'B', 'a'), (3, 'C', 'a'), (4, 'A', 'd');   INSERT #Changes (pk, status_code) VALUES (1, 'd'), (4, 'a');          Target                     Changes +-----------------------+    +------------------+ ¦ pk ¦ ak ¦ status_code ¦    ¦ pk ¦ status_code ¦ ¦----+----+-------------¦    ¦----+-------------¦ ¦  1 ¦ A  ¦ a           ¦    ¦  1 ¦ d           ¦ ¦  2 ¦ B  ¦ a           ¦    ¦  4 ¦ a           ¦ ¦  3 ¦ C  ¦ a           ¦    +------------------+ ¦  4 ¦ A  ¦ d           ¦ +-----------------------+ The target table’s alternate key (ak) column is unique, for rows where status_code = ‘a’.  Applying the changes to the target will change row 1 from status ‘a’ to status ‘d’, and row 4 from status ‘d’ to status ‘a’.  The result of applying all the changes will still satisfy the filtered unique index, because the ‘A’ in row 1 will be deleted from the index and the ‘A’ in row 4 will be added. Merge Test One Let’s now execute a MERGE statement to apply the changes: MERGE #Target AS t USING #Changes AS c ON c.pk = t.pk WHEN MATCHED AND c.status_code <> t.status_code THEN UPDATE SET status_code = c.status_code; The MERGE changes the two target rows as expected.  The updated target table now contains: +-----------------------+ ¦ pk ¦ ak ¦ status_code ¦ ¦----+----+-------------¦ ¦  1 ¦ A  ¦ d           ¦ <—changed from ‘a’ ¦  2 ¦ B  ¦ a           ¦ ¦  3 ¦ C  ¦ a           ¦ ¦  4 ¦ A  ¦ a           ¦ <—changed from ‘d’ +-----------------------+ Merge Test Two Now let’s repopulate the changes table to reverse the updates we just performed: TRUNCATE TABLE #Changes;   INSERT #Changes (pk, status_code) VALUES (1, 'a'), (4, 'd'); This will change row 1 back to status ‘a’ and row 4 back to status ‘d’.  As a reminder, the current state of the tables is:          Target                        Changes +-----------------------+    +------------------+ ¦ pk ¦ ak ¦ status_code ¦    ¦ pk ¦ status_code ¦ ¦----+----+-------------¦    ¦----+-------------¦ ¦  1 ¦ A  ¦ d           ¦    ¦  1 ¦ a           ¦ ¦  2 ¦ B  ¦ a           ¦    ¦  4 ¦ d           ¦ ¦  3 ¦ C  ¦ a           ¦    +------------------+ ¦  4 ¦ A  ¦ a           ¦ +-----------------------+ We execute the same MERGE statement: MERGE #Target AS t USING #Changes AS c ON c.pk = t.pk WHEN MATCHED AND c.status_code <> t.status_code THEN UPDATE SET status_code = c.status_code; However this time we receive the following message: Msg 2601, Level 14, State 1, Line 1 Cannot insert duplicate key row in object 'dbo.#Target' with unique index 'uq1'. The duplicate key value is (A). The statement has been terminated. Applying the changes using UPDATE Let’s now rewrite the MERGE to use UPDATE instead: UPDATE t SET status_code = c.status_code FROM #Target AS t JOIN #Changes AS c ON t.pk = c.pk WHERE c.status_code <> t.status_code; This query succeeds where the MERGE failed.  The two rows are updated as expected: +-----------------------+ ¦ pk ¦ ak ¦ status_code ¦ ¦----+----+-------------¦ ¦  1 ¦ A  ¦ a           ¦ <—changed back to ‘a’ ¦  2 ¦ B  ¦ a           ¦ ¦  3 ¦ C  ¦ a           ¦ ¦  4 ¦ A  ¦ d           ¦ <—changed back to ‘d’ +-----------------------+ What went wrong with the MERGE? In this test, the MERGE query execution happens to apply the changes in the order of the ‘pk’ column. In test one, this was not a problem: row 1 is removed from the unique filtered index by changing status_code from ‘a’ to ‘d’ before row 4 is added.  At no point does the table contain two rows where ak = ‘A’ and status_code = ‘a’. In test two, however, the first change was to change row 1 from status ‘d’ to status ‘a’.  This change means there would be two rows in the filtered unique index where ak = ‘A’ (both row 1 and row 4 meet the index filtering criteria ‘status_code = a’). The storage engine does not allow the query processor to violate a unique key (unless IGNORE_DUP_KEY is ON, but that is a different story, and doesn’t apply to MERGE in any case).  This strict rule applies regardless of the fact that if all changes were applied, there would be no unique key violation (row 4 would eventually be changed from ‘a’ to ‘d’, removing it from the filtered unique index, and resolving the key violation). Why it went wrong The query optimizer usually detects when this sort of temporary uniqueness violation could occur, and builds a plan that avoids the issue.  I wrote about this a couple of years ago in my post Beware Sneaky Reads with Unique Indexes (you can read more about the details on pages 495-497 of Microsoft SQL Server 2008 Internals or in Craig Freedman’s blog post on maintaining unique indexes).  To summarize though, the optimizer introduces Split, Filter, Sort, and Collapse operators into the query plan to: Split each row update into delete followed by an inserts Filter out rows that would not change the index (due to the filter on the index, or a non-updating update) Sort the resulting stream by index key, with deletes before inserts Collapse delete/insert pairs on the same index key back into an update The effect of all this is that only net changes are applied to an index (as one or more insert, update, and/or delete operations).  In this case, the net effect is a single update of the filtered unique index: changing the row for ak = ‘A’ from pk = 4 to pk = 1.  In case that is less than 100% clear, let’s look at the operation in test two again:          Target                     Changes                   Result +-----------------------+    +------------------+    +-----------------------+ ¦ pk ¦ ak ¦ status_code ¦    ¦ pk ¦ status_code ¦    ¦ pk ¦ ak ¦ status_code ¦ ¦----+----+-------------¦    ¦----+-------------¦    ¦----+----+-------------¦ ¦  1 ¦ A  ¦ d           ¦    ¦  1 ¦ d           ¦    ¦  1 ¦ A  ¦ a           ¦ ¦  2 ¦ B  ¦ a           ¦    ¦  4 ¦ a           ¦    ¦  2 ¦ B  ¦ a           ¦ ¦  3 ¦ C  ¦ a           ¦    +------------------+    ¦  3 ¦ C  ¦ a           ¦ ¦  4 ¦ A  ¦ a           ¦                            ¦  4 ¦ A  ¦ d           ¦ +-----------------------+                            +-----------------------+ From the filtered index’s point of view (filtered for status_code = ‘a’ and shown in nonclustered index key order) the overall effect of the query is:   Before           After +---------+    +---------+ ¦ pk ¦ ak ¦    ¦ pk ¦ ak ¦ ¦----+----¦    ¦----+----¦ ¦  4 ¦ A  ¦    ¦  1 ¦ A  ¦ ¦  2 ¦ B  ¦    ¦  2 ¦ B  ¦ ¦  3 ¦ C  ¦    ¦  3 ¦ C  ¦ +---------+    +---------+ The single net change there is a change of pk from 4 to 1 for the nonclustered index entry ak = ‘A’.  This is the magic performed by the split, sort, and collapse.  Notice in particular how the original changes to the index key (on the ‘ak’ column) have been transformed into an update of a non-key column (pk is included in the nonclustered index).  By not updating any nonclustered index keys, we are guaranteed to avoid transient key violations. The Execution Plans The estimated MERGE execution plan that produces the incorrect key-violation error looks like this (click to enlarge in a new window): The successful UPDATE execution plan is (click to enlarge in a new window): The MERGE execution plan is a narrow (per-row) update.  The single Clustered Index Merge operator maintains both the clustered index and the filtered nonclustered index.  The UPDATE plan is a wide (per-index) update.  The clustered index is maintained first, then the Split, Filter, Sort, Collapse sequence is applied before the nonclustered index is separately maintained. There is always a wide update plan for any query that modifies the database. The narrow form is a performance optimization where the number of rows is expected to be relatively small, and is not available for all operations.  One of the operations that should disallow a narrow plan is maintaining a unique index where intermediate key violations could occur. Workarounds The MERGE can be made to work (producing a wide update plan with split, sort, and collapse) by: Adding all columns referenced in the filtered index’s WHERE clause to the index key (INCLUDE is not sufficient); or Executing the query with trace flag 8790 set e.g. OPTION (QUERYTRACEON 8790). Undocumented trace flag 8790 forces a wide update plan for any data-changing query (remember that a wide update plan is always possible).  Either change will produce a successfully-executing wide update plan for the MERGE that failed previously. Conclusion The optimizer fails to spot the possibility of transient unique key violations with MERGE under the conditions listed at the start of this post.  It incorrectly chooses a narrow plan for the MERGE, which cannot provide the protection of a split/sort/collapse sequence for the nonclustered index maintenance. The MERGE plan may fail at execution time depending on the order in which rows are processed, and the distribution of data in the database.  Worse, a previously solid MERGE query may suddenly start to fail unpredictably if a filtered unique index is added to the merge target table at any point. Connect bug filed here Tests performed on SQL Server 2012 SP1 CUI (build 11.0.3321) x64 Developer Edition © 2012 Paul White – All Rights Reserved Twitter: @SQL_Kiwi Email: [email protected]

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  • CodePlex Daily Summary for Wednesday, March 09, 2011

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This only came to light after releasing, and will be fixed in the next one.Microsoft All-In-One Code Framework: Visual Studio 2008 Code Samples 2011-03-09: Code samples for Visual Studio 2008myCollections: Version 1.3: New in version 1.3 : Added Editor management for Books Added Amazon API for Books Us, Fr, De Added Amazon Us, Fr, De for Movies Added The MovieDB for Fr and De Added Author for Books Added Editor and Platform for Games Added Amazon Us, De for Games Added Studio for XXX Added Background for XXX Bug fixing with Softonic API Bug fixing with IMDB UI improvement Removed GraceNote Added Amazon Us,Fr, De for Series Added TVDB Fr and De for Series Added Tracks for Musi...Facebook Graph Toolkit: Facebook Graph Toolkit 1.1: Version 1.1 (8 Mar 2011)new Dialog class for redirecting users to Facebook dialogs new Async publishing methods new Check for Extended Permissions option fixed bug: inappropiate condition of redirecting to login in Api class fixed bug: IframeRedirect method not workingpatterns & practices : Composite Services: Composite Services Guidance - CTP2: This is the second CTP of the p&p Composite Service Guidance.Python Tools for Visual Studio: 1.0 Beta 1: Beta 1You can't install IronPython Tools for Visual Studio side-by-side with Python Tools for Visual Studio. 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Change Log from 0.9.2 to 1.0: ==================== Added: > Added Icon Overlay for Windows 7 Taskbar Icon. >Added Thumbnail Toolbar buttons to make the navigation easier...Chirpy - VS Add In For Handling Js, Css, DotLess, and T4 Files: Margogype Chirpy (ver 2.0): Chirpy loves Americans. Chirpy hates Americanos.ASP.NET: Sprite and Image Optimization Preview 3: The ASP.NET Sprite and Image Optimization framework is designed to decrease the amount of time required to request and display a page from a web server by performing a variety of optimizations on the page’s images. This is the third preview of the feature and works with ASP.NET Web Forms 4, ASP.NET MVC 3, and ASP.NET Web Pages (Razor) projects. The binaries are also available via NuGet: AspNetSprites-Core AspNetSprites-WebFormsControl AspNetSprites-MvcAndRazorHelper It includes the foll...New ProjectsA-Inventory: Inventory Management System * Purchase Orders * Sales Orders * Multiple warehouses * Stock Transfers * Financial Transaction Tracking * ReportsAsync Execution Lib: This library simplifies the process of executing code on a different thread and separating the caller from the actual command logic. To do this messages are put into an execution module and the library automatically calls the target message handlers.Bing Wallpaper Downloader: Downloads wallpapers from Bing and displays them as the desktop wallpaper. Based on UI and concepts of Bing4Free.CloudBox: This is a custom storage controller for DropBox. It lets you create multiple DropBox accounts an will then treat them as one large storage. Controller2: Projeto para desenvolvimento de Sistema para o Projeto Integrador do Curso de Análise e Desenvolvimento de Sistemas do CesumarCurso_Virtual_FPSEP: En este proyecto se esta elaborando el sistema para el manejo de un curso virtual que se tiene pensado impartir en la CFE, este curso se esta desarrollando bajo el mando del Ingeniero Earl Amazurrutia Carson y esta dirigido para el personal de protecciones.DBSJ: testEveTools: EveTools is a set of classes to aid in the development of programs that access the EVE Online API. It is written with a very event-driven model; all normally blocking, non-compute-bound workloads will instead run asynchronously, freeing up your program to do as it pleases!GeoIp: .Net MaxMind GeoIP client libraryKieuHungProject: Doan Vien managmentMimoza: ?????? ??? ????? ?????????, ??????? ????? ???????????? ??? ?????? ????????? ???????????? ?? ?????? ??????...mmoss: Medical Marijuana Open Source System. To manage Point-of-sale, inventory, grow and compliance issues related to the sale of MMJNetCassa: .Net Cassandra client library.Neudesic Pulse SDK: The Neudesic Pulse SDK allows developers the ability to quickly and efficiently build solutions that interact with the Neudesic Pulse social framework APIs.Nuget Package Creation and Publishing Wizard: simplifies the creation and publishing of an nuget packagePetscareinlondon: This project is all about pets care.Pool based Batch Processing: A simple framework that allows pool based processing of batches. A new batch is picked up when pools are empty. The framework exposes simple events that allows user to process jobs at the back end (Windows Service).Project Nonnon: Keep-It-Simple Softwares for Win32 MinGW GCC 3.x C Language + Batch Files POSIX-based Base Layer Library Win32 Applications Easy2Compile Easy2Make Easy2Use Python Tools for Visual Studio: Python Tools for Visual Studio adds support for Intellisense, Debugging, Profiling, IPython (.11+), Cluster & Cloud Computing to Visual Studio. It supports both CPython (2.4-3.1) and IronPython (2.7). python_lib: like protobuf,parse xml definition of c++struct,and develop lots of usageRapidMEF: A collection of tools to help developers author and debug applications that use MEF.Reflective: Reflective adds lots of new extension methods related to reflection and Reflection.Emit, to make it easier to build code dynamically at runtime.Remote Desktop Organizer: This is a fun little application that lets you easily manage lots of different Remote Desktops. It allows the user to apply custom alias's and descriptions so that it is easy denote which desktop is which and allows for easy customization and managementSharePoint data population: SharePoint data populationSpriteEditor: Basic sprite editorStock3243254635254325435: 345234324324324324Time Management Application: Based upon Stephen Covey's 7 Habits of Highly Effective People, I was looking for a place to digitally record my time. When I could not find one I liked, I set out to build my own. This also covers several of the coding practices and patterns that I have been putting together.Tuned N: Tuned N is a Playlist.com based media application. Allows listening to playlists via desktop app and allows downloading of tracks in playlists.Winforms BetterBindingSource: A better windows forms (winforms) bindingsource control which enables you to add class based datasources without the hassle of adding datasource files and using the slow wizard to add data sources.WinShutdown: Just a small application to countdown the windows shutdown/restart. When you want the windows shutdown after some time or after some application finishes its work. Please if you have a better project for this purpouse or if you have an update for my code. Let me know.

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  • CodePlex Daily Summary for Thursday, March 10, 2011

    CodePlex Daily Summary for Thursday, March 10, 2011Popular ReleasesTweetSharp: TweetSharp v2.0.0: Documentation for this release may be found at http://tweetsharp.codeplex.com/wikipage?title=UserGuide&referringTitle=Documentation. Beta ChangesAdded user streams support Serialization is not attempted for Twitter 5xx errors Fixes based on feedback Third Party Library VersionsHammock v1.2.0: http://hammock.codeplex.com Json.NET 4.0 Release 1: http://json.codeplex.comSharePoint Field Groups To Users: GroupsToUsers Release 1.0: SharePoint "Groups to Users" is a custom field that displays two separate drop-down lists. The first drop-down populates with all SharePoint Groups from the current web. By selecting a particular group the second drop-down list gets populated with all Users within the selected SharePoint group.DirectQ: Release 1.8.7 (RC2): More fixes and improvements. Note for multiplayer - you may need to set r_waterwarp to 0 or 2 before connecting to a server, otherwise you will get a "Mod_PointInLeaf: bad model" error and not be able to connect. You can set it back to 1 after you connect, of course. This only came to light after releasing, and will be fixed in the next one.Microsoft All-In-One Code Framework: Visual Studio 2008 Code Samples 2011-03-09: Code samples for Visual Studio 2008Office Web.UI: Version 2.4: After having lost all modifications done for 2.3. I finally did it again... Have a look at http://www.officewebui.com/change-log Also, the documentation continues to grow... http://www.officewebui.com/category/kb ThanksmyCollections: Version 1.3: New in version 1.3 : Added Editor management for Books Added Amazon API for Books Us, Fr, De Added Amazon Us, Fr, De for Movies Added The MovieDB for Fr and De Added Author for Books Added Editor and Platform for Games Added Amazon Us, De for Games Added Studio for XXX Added Background for XXX Bug fixing with Softonic API Bug fixing with IMDB UI improvement Removed GraceNote Added Amazon Us,Fr, De for Series Added TVDB Fr and De for Series Added Tracks for Musi...Facebook Graph Toolkit: Facebook Graph Toolkit 1.1: Version 1.1 (8 Mar 2011)new Dialog class for redirecting users to Facebook dialogs new Async publishing methods new Check for Extended Permissions option fixed bug: inappropiate condition of redirecting to login in Api class fixed bug: IframeRedirect method not workingpatterns & practices : Composite Services: Composite Services Guidance - CTP2: This is the second CTP of the p&p Composite Service Guidance.Python Tools for Visual Studio: 1.0 Beta 1: Beta 1You can't install IronPython Tools for Visual Studio side-by-side with Python Tools for Visual Studio. A race condition sometimes causes local MPI debugging to miss breakpoints. When MPI jobs on a cluster fail they don’t get cleaned up correctly, which can cause debugging to stall because the associated MPI job is stuck in the queue. The "Threads" view has a race condition which can cause it not to display properly at times. VS2010 shortcuts that are pinned to the taskbar are so...DotNetAge -a lightweight Mvc jQuery CMS: DotNetAge 2: What is new in DotNetAge 2.0 ? Completely update DJME to DJME2, enhance user experience ,more beautiful and more interactively visit DJME project home to lean more about DJME http://www.dotnetage.com/sites/home/djme.html A new widget engine has came! Faster and easiler. Runtime performance enhanced. SEO enhanced. UI Designer enhanced. A new web resources explorer. Page manager enhanced. BlogML supports added that allows you import/export your blog data to/from dotnetage publishi...Kooboo CMS: Kooboo CMS 3.0 Beta: Files in this downloadkooboo_CMS.zip: The kooboo application files Content_DBProvider.zip: Additional content database implementation of MSSQL,SQLCE, RavenDB and MongoDB. Default is XML based database. To use them, copy the related dlls into web root bin folder and remove old content provider dlls. Content provider has the name like "Kooboo.CMS.Content.Persistence.SQLServer.dll" View_Engines.zip: Supports of Razor, webform and NVelocity view engine. Copy the dlls into web root bin folder t...ASP.NET MVC Project Awesome, jQuery Ajax helpers (controls): 1.7.2: A rich set of helpers (controls) that you can use to build highly responsive and interactive Ajax-enabled Web applications. These helpers include Autocomplete, AjaxDropdown, Lookup, Confirm Dialog, Popup Form, Popup and Pager added fullscreen for the popup and popupformIronPython: 2.7 Release Candidate 2: On behalf of the IronPython team, I am pleased to announce IronPython 2.7 Release Candidate 2. The releases contains a few minor bug fixes, including a working webbrowser module. Please see the release notes for 61395 for what was fixed in previous releases.LINQ to Twitter: LINQ to Twitter Beta v2.0.20: Mono 2.8, Silverlight, OAuth, 100% Twitter API coverage, streaming, extensibility via Raw Queries, and added documentation.Minemapper: Minemapper v0.1.6: Once again supports biomes, thanks to an updated Minecraft Biome Extractor, which added support for the new Minecraft beta v1.3 map format. Updated mcmap to support new biome format.Sandcastle Help File Builder: SHFB v1.9.3.0 Release: This release supports the Sandcastle June 2010 Release (v2.6.10621.1). It includes full support for generating, installing, and removing MS Help Viewer files. This new release is compiled under .NET 4.0, supports Visual Studio 2010 solutions and projects as documentation sources, and adds support for projects targeting the Silverlight Framework. This release uses the Sandcastle Guided Installation package used by Sandcastle Styles. Download and extract to a folder and then run SandcastleI...AutoLoL: AutoLoL v1.6.4: It is now possible to run the clicker anyway when it can't detect the Masteries Window Fixed a critical bug in the open file dialog Removed the resize button Some UI changes 3D camera movement is now more intuitive (Trackball rotation) When an error occurs on the clicker it will attempt to focus AutoLoLYAF.NET (aka Yet Another Forum.NET): v1.9.5.5 RTW: YAF v1.9.5.5 RTM (Date: 3/4/2011 Rev: 4742) Official Discussion Thread here: http://forum.yetanotherforum.net/yaf_postsm47149_v1-9-5-5-RTW--Date-3-4-2011-Rev-4742.aspx Changes in v1.9.5.5 Rev. #4661 - Added "Copy" function to forum administration -- Now instead of having to manually re-enter all the access masks, etc, you can just duplicate an existing forum and modify after the fact. Rev. #4642 - New Setting to Enable/Disable Last Unread posts links Rev. #4641 - Added Arabic Language t...Snippet Designer: Snippet Designer 1.3.1: Snippet Designer 1.3.1 for Visual Studio 2010This is a bug fix release. Change logFixed bug where Snippet Designer would fail if you had the most recent Productivity Power Tools installed Fixed bug where "Export as Snippet" was failing in non-english locales Fixed bug where opening a new .snippet file would fail in non-english localesChiave File Encryption: Chiave 1.0: Final Relase for Chave 1.0 Stable: Application for file encryption and decryption using 512 Bit rijndael encyrption algorithm with simple to use UI. Its written in C# and compiled in .Net version 3.5. It incorporates features of Windows 7 like Jumplists, Taskbar progress and Aero Glass. Now with added support to Windows XP! Change Log from 0.9.2 to 1.0: ==================== Added: > Added Icon Overlay for Windows 7 Taskbar Icon. >Added Thumbnail Toolbar buttons to make the navigation easier...New ProjectsAll2Iso: Convert any disk image format to ISO. Actually it can only convert from BIN. Any help is appreciated.Asset Management by Joko for GENCPROS: This is my initial test project using codeplex storageAxvius: Axvius' core C# API library. Includes, Now, a class for overriding the system clock; especially useful for unit tests.Collision Avoidance Simulator: The vertex buff er, in conjunction with the spatial con guration of human models, a particle system and a reduced set of rules are processed in order to obtain a dynamic knowledge base for collision avoidance calculations. Developed in C++.Configuring role link in Biztalk 2009: Configuring role link in Biztalk 2009CrazySnake: Crazy Snake é o famoso jogo da cobra, esse em sua versão tanto para windows, quanto para windows phone 7dIRca WP7 IRC Client: IRC client with possible SL/WPF ports. Utilizes native tcp sockets until the communication layer from MS solidifies. Basically put, this project would not exist without the work of some wp7 hackers. Pip pip old boys.DoanVienProject: Ðây là porject qu?n lý doàn viênDynamics AX Build Scripts: Sharing build scripts for Dynamics AX integration with source control, focused on Team Foundation Server (TFS)EPiServer CMS ElencySolutions.MultipleProperty: The MultipleProperty classes are for use in EPiServer CMS 6 and provide an easy way for developers to build complex custom properties that comprise of other EPiServer custom properties. Feriados Móveis Brasil: This project aim to calculate the holidays in Brazil who is based on catholic dates. The main holiday is the Easter Sunday and the other holidays are calculated based on that date. Cálculo de feriados móveis para o Brasil baseados nas datas festivas católicas.flyskynet: myselft projectGriffTom: GriffTomImage Resizer (????????): ??????????????????,????????????????。?????jpg??。 ??????,????????????。iPray: Islamic Prayer Software.Japanese Learners & Enthusiasts Kanji Project: Help create games, puzzles, and exercises to assist learners of Japanese to master Kanji comprehension. Games/etc. will be written in C#, jQuery and/or Silverlight for ASP.NET MVC 3 Razor. Initial goal is for a user of the site to master grade level 1 Kanji (first 80 Kanji).MailChimp Amazon Simple Email Service .NET Wrapper: A .NET 4 wrapper for MailChimp's Amazon Simple Email Service. It's developed in C# using Hammock.NGuice: .NET????Guice???????????。???.NET?????????,?Guice?.NET??????????。???????:http://code.google.com/p/google-guice/Rubrica Persone: Libreria che contiene gli oggetti e le form per la gestione di una rubrica di persone, facilmente integrabile in altre applicazioni.SCCM Client Center Integration Pack for Opalis: "SCCM Client Center Integration Pack for Opalis" is an System Center Opalis Integration Pack to manage and orchestrate System Center Configuration Manager (SCCM) 2007 Agents from Opalis workflows.Sugar-free programming: I like to think about breadth or depth developer, or Mort, Elvis, or Einstein developer stereotypes, as roles we could play accordingly to the task at hand…see more: http://blogs.msdn.com/b/marcod/archive/2011/03/01/sugarfreecs1.aspxTest Project 1: This is test project siteTestZoner: TestZoneTextBookReader: ???????????????????????,??????????,??????! ??.net 2.0uSiteBuilder: uSiteBuilder is a framework made for .NET developers to simplify, speedup and take Umbraco development to next level. Aim of this framework is to reduce developer interaction with Umbraco back-end (browser based development), to create Umbraco websites in a more .NET way...VinculacionMicrosoft: Vinculacion Microsoft is a project for distributing Dreamsparks and Faculty Connection codes to students and professors. It is developed in ASP .Net and designed for Universities in Mexico interested in the different benefits that Microsoft has for them. Vio: Vio is an application for Sharetronix Based websites. Allowing users to connect to their community via their Windows Desktop.whatsnew.exe a command line utility to find new files: whatsnew.exe is a command line utility that lists the files created (new files) in a given number of days. whatsnew.exe 's syntax is very simple: whatsnew path numberofdays Also whatsnew supports other options like HTML or XML output, hyperlinked outputs and more.

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  • .NET Code Evolution

    - by Alois Kraus
    Originally posted on: http://geekswithblogs.net/akraus1/archive/2013/07/24/153504.aspxAt my day job I do look at a lot of code written by other people. Most of the code is quite good and some is even a masterpiece. And there is also code which makes you think WTF… oh it was written by me. Hm not so bad after all. There are many excuses reasons for bad code. Most often it is time pressure followed by not enough ambition (who cares) or insufficient training. Normally I do care about code quality quite a lot which makes me a (perceived) slow worker who does write many tests and refines the code quite a lot because of the design deficiencies. Most of the deficiencies I do find by putting my design under stress while checking for invariants. It does also help a lot to step into the code with a debugger (sometimes also Windbg). I do this much more often when my tests are red. That way I do get a much better understanding what my code really does and not what I think it should be doing. This time I do want to show you how code can evolve over the years with different .NET Framework versions. Once there was  time where .NET 1.1 was new and many C++ programmers did switch over to get rid of not initialized pointers and memory leaks. There were also nice new data structures available such as the Hashtable which is fast lookup table with O(1) time complexity. All was good and much code was written since then. At 2005 a new version of the .NET Framework did arrive which did bring many new things like generics and new data structures. The “old” fashioned way of Hashtable were coming to an end and everyone used the new Dictionary<xx,xx> type instead which was type safe and faster because the object to type conversion (aka boxing) was no longer necessary. I think 95% of all Hashtables and dictionaries use string as key. Often it is convenient to ignore casing to make it easy to look up values which the user did enter. An often followed route is to convert the string to upper case before putting it into the Hashtable. Hashtable Table = new Hashtable(); void Add(string key, string value) { Table.Add(key.ToUpper(), value); } This is valid and working code but it has problems. First we can pass to the Hashtable a custom IEqualityComparer to do the string matching case insensitive. Second we can switch over to the now also old Dictionary type to become a little faster and we can keep the the original keys (not upper cased) in the dictionary. Dictionary<string, string> DictTable = new Dictionary<string, string>(StringComparer.OrdinalIgnoreCase); void AddDict(string key, string value) { DictTable.Add(key, value); } Many people do not user the other ctors of Dictionary because they do shy away from the overhead of writing their own comparer. They do not know that .NET has for strings already predefined comparers at hand which you can directly use. Today in the many core area we do use threads all over the place. Sometimes things break in subtle ways but most of the time it is sufficient to place a lock around the offender. Threading has become so mainstream that it may sound weird that in the year 2000 some guy got a huge incentive for the idea to reduce the time to process calibration data from 12 hours to 6 hours by using two threads on a dual core machine. Threading does make it easy to become faster at the expense of correctness. Correct and scalable multithreading can be arbitrarily hard to achieve depending on the problem you are trying to solve. Lets suppose we want to process millions of items with two threads and count the processed items processed by all threads. A typical beginners code might look like this: int Counter; void IJustLearnedToUseThreads() { var t1 = new Thread(ThreadWorkMethod); t1.Start(); var t2 = new Thread(ThreadWorkMethod); t2.Start(); t1.Join(); t2.Join(); if (Counter != 2 * Increments) throw new Exception("Hmm " + Counter + " != " + 2 * Increments); } const int Increments = 10 * 1000 * 1000; void ThreadWorkMethod() { for (int i = 0; i < Increments; i++) { Counter++; } } It does throw an exception with the message e.g. “Hmm 10.222.287 != 20.000.000” and does never finish. The code does fail because the assumption that Counter++ is an atomic operation is wrong. The ++ operator is just a shortcut for Counter = Counter + 1 This does involve reading the counter from a memory location into the CPU, incrementing value on the CPU and writing the new value back to the memory location. When we do look at the generated assembly code we will see only inc dword ptr [ecx+10h] which is only one instruction. Yes it is one instruction but it is not atomic. All modern CPUs have several layers of caches (L1,L2,L3) which try to hide the fact how slow actual main memory accesses are. Since cache is just another word for redundant copy it can happen that one CPU does read a value from main memory into the cache, modifies it and write it back to the main memory. The problem is that at least the L1 cache is not shared between CPUs so it can happen that one CPU does make changes to values which did change in meantime in the main memory. From the exception you can see we did increment the value 20 million times but half of the changes were lost because we did overwrite the already changed value from the other thread. This is a very common case and people do learn to protect their  data with proper locking.   void Intermediate() { var time = Stopwatch.StartNew(); Action acc = ThreadWorkMethod_Intermediate; var ar1 = acc.BeginInvoke(null, null); var ar2 = acc.BeginInvoke(null, null); ar1.AsyncWaitHandle.WaitOne(); ar2.AsyncWaitHandle.WaitOne(); if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Intermediate did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Intermediate() { for (int i = 0; i < Increments; i++) { lock (this) { Counter++; } } } This is better and does use the .NET Threadpool to get rid of manual thread management. It does give the expected result but it can result in deadlocks because you do lock on this. This is in general a bad idea since it can lead to deadlocks when other threads use your class instance as lock object. It is therefore recommended to create a private object as lock object to ensure that nobody else can lock your lock object. When you read more about threading you will read about lock free algorithms. They are nice and can improve performance quite a lot but you need to pay close attention to the CLR memory model. It does make quite weak guarantees in general but it can still work because your CPU architecture does give you more invariants than the CLR memory model. For a simple counter there is an easy lock free alternative present with the Interlocked class in .NET. As a general rule you should not try to write lock free algos since most likely you will fail to get it right on all CPU architectures. void Experienced() { var time = Stopwatch.StartNew(); Task t1 = Task.Factory.StartNew(ThreadWorkMethod_Experienced); Task t2 = Task.Factory.StartNew(ThreadWorkMethod_Experienced); t1.Wait(); t2.Wait(); if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Experienced did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Experienced() { for (int i = 0; i < Increments; i++) { Interlocked.Increment(ref Counter); } } Since time does move forward we do not use threads explicitly anymore but the much nicer Task abstraction which was introduced with .NET 4 at 2010. It is educational to look at the generated assembly code. The Interlocked.Increment method must be called which does wondrous things right? Lets see: lock inc dword ptr [eax] The first thing to note that there is no method call at all. Why? Because the JIT compiler does know very well about CPU intrinsic functions. Atomic operations which do lock the memory bus to prevent other processors to read stale values are such things. Second: This is the same increment call prefixed with a lock instruction. The only reason for the existence of the Interlocked class is that the JIT compiler can compile it to the matching CPU intrinsic functions which can not only increment by one but can also do an add, exchange and a combined compare and exchange operation. But be warned that the correct usage of its methods can be tricky. If you try to be clever and look a the generated IL code and try to reason about its efficiency you will fail. Only the generated machine code counts. Is this the best code we can write? Perhaps. It is nice and clean. But can we make it any faster? Lets see how good we are doing currently. Level Time in s IJustLearnedToUseThreads Flawed Code Intermediate 1,5 (lock) Experienced 0,3 (Interlocked.Increment) Master 0,1 (1,0 for int[2]) That lock free thing is really a nice thing. But if you read more about CPU cache, cache coherency, false sharing you can do even better. int[] Counters = new int[12]; // Cache line size is 64 bytes on my machine with an 8 way associative cache try for yourself e.g. 64 on more modern CPUs void Master() { var time = Stopwatch.StartNew(); Task t1 = Task.Factory.StartNew(ThreadWorkMethod_Master, 0); Task t2 = Task.Factory.StartNew(ThreadWorkMethod_Master, Counters.Length - 1); t1.Wait(); t2.Wait(); Counter = Counters[0] + Counters[Counters.Length - 1]; if (Counter != 2 * Increments) throw new Exception(String.Format("Hmm {0:N0} != {1:N0}", Counter, 2 * Increments)); Console.WriteLine("Master did take: {0:F1}s", time.Elapsed.TotalSeconds); } void ThreadWorkMethod_Master(object number) { int index = (int) number; for (int i = 0; i < Increments; i++) { Counters[index]++; } } The key insight here is to use for each core its own value. But if you simply use simply an integer array of two items, one for each core and add the items at the end you will be much slower than the lock free version (factor 3). Each CPU core has its own cache line size which is something in the range of 16-256 bytes. When you do access a value from one location the CPU does not only fetch one value from main memory but a complete cache line (e.g. 16 bytes). This means that you do not pay for the next 15 bytes when you access them. This can lead to dramatic performance improvements and non obvious code which is faster although it does have many more memory reads than another algorithm. So what have we done here? We have started with correct code but it was lacking knowledge how to use the .NET Base Class Libraries optimally. Then we did try to get fancy and used threads for the first time and failed. Our next try was better but it still had non obvious issues (lock object exposed to the outside). Knowledge has increased further and we have found a lock free version of our counter which is a nice and clean way which is a perfectly valid solution. The last example is only here to show you how you can get most out of threading by paying close attention to your used data structures and CPU cache coherency. Although we are working in a virtual execution environment in a high level language with automatic memory management it does pay off to know the details down to the assembly level. Only if you continue to learn and to dig deeper you can come up with solutions no one else was even considering. I have studied particle physics which does help at the digging deeper part. Have you ever tried to solve Quantum Chromodynamics equations? Compared to that the rest must be easy ;-). Although I am no longer working in the Science field I take pride in discovering non obvious things. This can be a very hard to find bug or a new way to restructure data to make something 10 times faster. Now I need to get some sleep ….

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  • cisco 2911 router vs 2811 router

    - by NickToyota
    Just wondering if anyone has experience with the cisco 2911 or 2900 series routers. I understand it is newer and similar to the 2811 but more robust. The price difference is not that much more. I am trying to determine if I should go with the 29xx or 28xx series for a small-medium sized company. ISP bandwidth load balancing and fail over is required. T1 and ADSL lines already in place.

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  • Dentrix database file

    - by user1050116
    I have dentrix database files, but i don't know which database engine support it. I read online that it support c-Tree database engine, but i am fail to open any files/database into it. Database file are like test.dat and test.idx and many more files are there like this file extensions only. Please help me this, how can i open these files and database. Which database engine will support to open these files?

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  • [Wireless LAN]hostapd is giving error whwn running in target board

    - by Renjith G
    hi, I got the following error when i tried to run the hostapd command in my target board. Any idea about this? /etc # hostapd -dd hostapd.conf Configuration file: hostapd.conf madwifi_set_iface_flags: dev_up=0 madwifi_set_privacy: enabled=0 BSS count 1, BSSID mask ff:ff:ff:ff:ff:ff (0 bits) Flushing old station entries madwifi_sta_deauth: addr=ff:ff:ff:ff:ff:ff reason_code=3 ioctl[IEEE80211_IOCTL_SETMLME]: Invalid argument madwifi_sta_deauth: Failed to deauth STA (addr ff:ff:ff:ff:ff:ff reason 3) Could not connect to kernel driver. Deauthenticate all stations madwifi_sta_deauth: addr=ff:ff:ff:ff:ff:ff reason_code=2 ioctl[IEEE80211_IOCTL_SETMLME]: Invalid argument madwifi_sta_deauth: Failed to deauth STA (addr ff:ff:ff:ff:ff:ff reason 2) madwifi_set_privacy: enabled=0 madwifi_del_key: addr=00:00:00:00:00:00 key_idx=0 madwifi_del_key: addr=00:00:00:00:00:00 key_idx=1 madwifi_del_key: addr=00:00:00:00:00:00 key_idx=2 madwifi_del_key: addr=00:00:00:00:00:00 key_idx=3 Using interface ath0 with hwaddr 00:0b:6b:33:8c:30 and ssid '"RG_WLAN Testing Renjith G"' SSID - hexdump_ascii(len=27): 22 52 47 5f 57 4c 41 4e 20 54 65 73 74 69 6e 67 "RG_WLAN Testing 20 52 65 6e 6a 69 74 68 20 47 22 Renjith G" PSK (ASCII passphrase) - hexdump_ascii(len=12): 6d 79 70 61 73 73 70 68 72 61 73 65 mypassphrase PSK (from passphrase) - hexdump(len=32): 70 6f a6 92 da 9c a8 3b ff 36 85 76 f3 11 9c 5e 5d 4a 4b 79 f4 4e 18 f6 b1 b8 09 af 6c 9c 6c 21 madwifi_set_ieee8021x: enabled=1 madwifi_configure_wpa: group key cipher=1 madwifi_configure_wpa: pairwise key ciphers=0xa madwifi_configure_wpa: key management algorithms=0x2 madwifi_configure_wpa: rsn capabilities=0x0 madwifi_configure_wpa: enable WPA=0x1 WPA: group state machine entering state GTK_INIT (VLAN-ID 0) GMK - hexdump(len=32): [REMOVED] GTK - hexdump(len=32): [REMOVED] WPA: group state machine entering state SETKEYSDONE (VLAN-ID 0) madwifi_set_key: alg=TKIP addr=00:00:00:00:00:00 key_idx=1 madwifi_set_privacy: enabled=1 madwifi_set_iface_flags: dev_up=1 ath0: Setup of interface done. l2_packet_receive - recvfrom: Network is down Wireless event: cmd=0x8b1a len=40 Register Fail Register Fail WPA: group state machine entering state SETKEYS (VLAN-ID 0) GMK - hexdump(len=32): [REMOVED] GTK - hexdump(len=32): [REMOVED] wpa_group_setkeys: GKeyDoneStations=0 WPA: group state machine entering state SETKEYSDONE (VLAN-ID 0) madwifi_set_key: alg=TKIP addr=00:00:00:00:00:00 key_idx=2 Signal 2 received - terminating Flushing old station entries madwifi_sta_deauth: addr=ff:ff:ff:ff:ff:ff reason_code=3 ioctl[IEEE80211_IOCTL_SETMLME]: Invalid argument madwifi_sta_deauth: Failed to deauth STA (addr ff:ff:ff:ff:ff:ff reason 3) Could not connect to kernel driver. Deauthenticate all stations madwifi_sta_deauth: addr=ff:ff:ff:ff:ff:ff reason_code=2 ioctl[IEEE80211_IOCTL_SETMLME]: Invalid argument madwifi_sta_deauth: Failed to deauth STA (addr ff:ff:ff:ff:ff:ff reason 2) madwifi_set_privacy: enabled=0 madwifi_set_ieee8021x: enabled=0 madwifi_set_iface_flags: dev_up=0

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  • there's no sudo command in cygwin

    - by Jason Sundram
    Because there's no sudo command in Cygwin, scripts that I want to run fail with ./install.sh: line N: sudo: command not found What's the standard way for getting around this? Editing the scripts to remove sudo? Getting some sudo-like tool for windows?

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  • Remote access to server via service control panel for non-admin user in Windows 2008

    - by owenevans00
    I'm trying to configure my Windows 2008 servers so that my developers can view their status without needing to log on to the box or be an admin. Unfortunately, the permissions set in Windows 2008 for remote non-admin users don't include the ability to enumerate or otherwise query services. This causes anything that contacts the SCM on the far end to fail (Win32_Service, sc.exe, services.msc etc). How do I set up permissions so that they can at least list the services and see if they are running?

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  • Windows 7 on laptop hard drive does not boot after installing Windows to Go on external hard drive

    - by user1687031
    Just successfully installed and ran Windows 8's Windows to Go on a USB external hard drive. However, after shutting down and removing the USB hard disk, whey I to start my laptop (with only Windows 7 installed), but it doesn't boot and trying to repair it doesn't work. It seems that Windows 8 had corrupted the partition table on the laptop's hard drive, causing Windows 7 to fail to boot. How do I fix that and avoid future problems of the same type?

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  • Proftp error message Fatal: unknown configuration directive 'DisplayFirstChdir' on line 22 of '/etc/proftpd/proftpd.conf'

    - by LedZeppelin
    Sorry for the newb factor but I'm trying to set up a server using this guide: http://www.intac.net/build-your-own-server/ I'm at the end of step 5 and when I try to restart proftp I get the following error message me@me-desktop:~$ sudo service proftpd restart * Stopping ftp server proftpd [ OK ] * Starting ftp server proftpd Fatal: unknown configuration directive 'DisplayFirstChdir' on line 22 of '/etc/proftpd/proftpd.conf' [fail] Any clues on how to change line 22?

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  • problem with enabling remote management of hyper-v server 2008 r2

    - by Pai Gaudêncio
    Howdy, I just recently installed hyper-v server 2008 r2 on a dedicated server i have, but i'm having trouble enabling remote management. Running the HVRemote - http://code.msdn.microsoft.com/HVRemote - tool seems to have yielded some positive results, and all tests on the server pass (firewall, permissions, etc), but client-side things are not working. I'm stuck at this step : 5: - Simple query to root\cimv2 WMI namespace FAIL - Simple query failed Cannot perform simple query against root\cimv2 Anyone could help me figure this out? I'm almost giving up and installing XenServer... Thanks

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  • Fresh XP Install: PS2 Keyboard not working

    - by RedLeader
    I reformatted a drive to NTFS (not quick) and installed Windows XP on it. Now it's trying to do the graphical portion of the setup, wanting me to click Accepts and Nexts... but I can't! The keyboard works to get to the BIOS and in the BIOS. I have reset the CMOS many times, tried fail-safe and optimized defaults, and even enabled USB Keyboard and mouse support (even though the I have no USB devices plugged in).

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  • Prevent scp from copying local files?

    - by ashcatch
    I just read the Linux scp command issue question and it reminded me that I regularily forget to specify the colon in the host part of a scp command, and thus copying a file locally instead of copying to a remote host, e.g. I do scp foo host instead of scp foo host: But I never use scp to copy a file locally. So I wonder if there is a way to make scp fail if both (the source and destination) arguments refer to local files.

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  • Python error after installing libboost-all-dev on debian [migrated]

    - by Cameron Metzke
    A friend of mine wanted the liboost libraries installed on our shared computer so after installing libboost-all-dev 1.49.0.1 ( A debian wheezy machine ), I get this error when using the "pydoc modules" command on the commandline. It spits out the following error -- root@debian:/usr/include/c++/4.7# pydoc modules Please wait a moment while I gather a list of all available modules... **[debian:49065] [[INVALID],INVALID] ORTE_ERROR_LOG: A system-required executable either could not be found or was not executable by this user in file ../../../../../../orte/mca/ess/singleton/ess_singleton_module.c at line 357 [debian:49065] [[INVALID],INVALID] ORTE_ERROR_LOG: A system-required executable either could not be found or was not executable by this user in file ../../../../../../orte/mca/ess/singleton/ess_singleton_module.c at line 230 [debian:49065] [[INVALID],INVALID] ORTE_ERROR_LOG: A system-required executable either could not be found or was not executable by this user in file ../../../orte/runtime/orte_init.c at line 132 -------------------------------------------------------------------------- It looks like orte_init failed for some reason; your parallel process is likely to abort. There are many reasons that a parallel process can fail during orte_init; some of which are due to configuration or environment problems. This failure appears to be an internal failure; here's some additional information (which may only be relevant to an Open MPI developer): orte_ess_set_name failed --> Returned value A system-required executable either could not be found or was not executable by this user (-127) instead of ORTE_SUCCESS -------------------------------------------------------------------------- -------------------------------------------------------------------------- It looks like MPI_INIT failed for some reason; your parallel process is likely to abort. There are many reasons that a parallel process can fail during MPI_INIT; some of which are due to configuration or environment problems. This failure appears to be an internal failure; here's some additional information (which may only be relevant to an Open MPI developer): ompi_mpi_init: orte_init failed --> Returned "A system-required executable either could not be found or was not executable by this user" (-127) instead of "Success" (0) -------------------------------------------------------------------------- *** The MPI_Init() function was called before MPI_INIT was invoked. *** This is disallowed by the MPI standard. *** Your MPI job will now abort. [debian:49065] Abort before MPI_INIT completed successfully; not able to guarantee that all other processes were killed!** root@debian:/usr/include/c++/4.7# I tried looking into the problem and ended up uninstalling the following to get it to work again. openmpi common all 1.4.5-1 libibverbs-dev amd64 1.1.6-1 libopenmpi-dev amd64 1.4.5-1 mpi-default-dev amd64 1.0.1 libboost-mpi-python1.49.0 although pydoc works again, I'm assuming the packages I removed are gunna hurt somethiong else down the track ? As you guessed im not a c/c++ programmer. So I guess my question is, will this hurt something later ? is their a way to install those packages without hurting python ?

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  • How do I install Ubuntu on Windows 7 with BitLocker?

    - by Sorin Sbarnea
    I installed Ubuntu 10.4 using Wubi on a Windows 7 x64 on the first partion that is NTFS and it's using BitLocker and it does fail to load. Is it Wubi incompatible with BitLocker or there is a way to configure the system without removing BitLocker and to make it work? Currently when I try to load Ubuntu I get No wbildr error message.

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  • Windows Cluster issue

    - by George2
    Hello everyone, For Windows Server 2008 failover cluster, I find it is dependent on Windows domain (in other words, Windows domain is pre-requisite of installing Windows Server 2008 fail over cluster). I am not sure why it is dependent on Windows domain? What features of Windows domain will Windows Server 2008 failover cluster utilize? thanks in advance, George

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  • Bind9 wont start on ubuntu 9.10

    - by Logikdev
    Ever since i've upgraded to ubuntu 9.10, bind9 wont start: Setting up bind9 (1:9.6.1.dfsg.P1-3ubuntu0.2) ... * Starting domain name service... bind9 [fail] invoke-rc.d: initscript bind9, action "start" failed. dpkg: error processing bind9 (--configure): subprocess installed post-installation script returned error exit status 1 Errors were encountered while processing: bind9 E: Sub-process /usr/bin/dpkg returned an error code (1) Any ideas?

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  • devcon.exe not working in Windows7 x64

    - by yas4891
    I can't use the ia64-version of devcon.exe on my Windows7 professional x64 (AMD CPU). error message tells me, that the version of this applcation is not suitable for this version of windows and I should check whether I need to use a x64 or x86 version of this application. The x86 version starts correctly, but all operations (remove, restart, disable etc) fail. Running from a command line with full privileges. Any ideas how to solve this?

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  • How can I detect upload success/failure in a scripted command-line SFTP session

    - by pkpk
    how can I detect success/failure sftp Batch script on Windows OS? I use %errorlevel% to detect success/failure, sometime the %errorlevel% be returned by 0, but that session is fail and the file is not upload to the server. my script is below how can I detect sftp uploaded correctly? THX so much @echo off (echo cd %4 echo put %2 echo exit)>sftpScript.txt sftp -b sftpScript.txt %3 set result=%errorlevel% if result EQU 0 ( del sftpScript.txt del %2 ) else ( del sftpScript.txt ) exit %result%

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  • KeePass justification

    - by Jeff Walker
    I work at a place that tries to take security seriously, but sadly, they often fail. Currently, one of the major ways they fail is password management. I personally have about 20 accounts (my personal user id on lots of machines). For shared "system" accounts, there are about 45 per environment; development, test, and production. I have access to 2 of those, so my personal total is somewhere around 115 accounts. Passwords have to be at least 15 characters with some extensive but standard complexity constraints, and have to be changed every 60 days or so (system accounts every year). They also should not be the same for different accounts, but that isn't enforced. Think DoD-type standards. There is no way to remember and keep up with this. It just isn't humanly possible, as far as I'm concerned. This might be a good justification of a centralized account management system, a la LDAP or ActiveDirectory, but that is a totally different battle. Currently the solution is an Excel spreadsheet. They use Excel to put a password on it, and then most people make a copy and remove the password. This makes my stomach turn. I use KeePass for this problem and it manages all of my account very well. I like the features like auto-typing, grouping, plugins, password generation, etc. It uses AES-256 encryption via the .Net framework, and while not FIPS compliant, it has a very good reputation. The only problem is that they are also very careful about using randomly downloaded software. So we have to justify every piece of software on our workstations. I have been told that they really don't want me to use this, be cause of the "sensitive nature" of storing passwords. sigh My justification has to be "VERY VERY strong". I have been tasked with writing a justification for KeePass, but as I am lazy, I would like any input that I can get from the community. What do you recommend? Is there something out there that is better or more respected than KeePass? Is there any security experts saying interesting things on this topic? Anything will help at this point. Thanks.

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  • Is there a good host for console applications?

    - by Jamey McElveen
    We have several applications that run in AppHarbor that we are bringing in-house. Our worker processes for AppHarbor are developed as windows console applications. What is the best way to host these console application in house? Of course I can just install and run them but I am hoping for a more managed way to host them. I want them to restart if they fail, ability to run multiple applications. These are things that were managed by AppHarbor. Thanks

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