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• ASP.NET retrieve Average CPU Usage

  - by Sam

  Last night I did a load test on a site. I found that one of my shared caches is a bottleneck. I'm using a ReaderWriterLockSlim to control the updates of the data. Unfortunately at one point there are ~200 requests trying to update the data at approximately the same time. This also coincided with CPU usage spikes. The data being updated is in the ASP.NET Cache. What I'd like to do is if the CPU usage is around 75%, I'd like to just skip the cache and hit the database on another machine. My problem is that I don't know how expensive it is to create a new performance counter to check the cpu usage. Also, if I would probably like the average cpu usage over the last 2 or 3 seconds. However, I can't sit there and calculate the cpu time as that would take longer than it's taking to update the cache currently. Is there an easy way to get the average CPU usage? Are there any drawbacks to this? I'm also considering totaling the wait count for the lock and then at a certain threshold switch over to the database. The concern I had with this approach would be that changing hardware might allow more locks with less of a strain on the system. And also finding the right balance for the threshold would be cumbersome and it doesn't take into account any other load on the machine. But it's a simple approach, and simple is 99% of the time better.

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• How do I abort a socket.recv() from another thread in python?

  - by Samuel Skånberg

  I have a main thread that waits for connection. It spawns client threads that will echo the response from the client (telnet in this case). But say that I want to close down all sockets and all threads after some time, like after 1 connection. How would I do? If I do clientSocket.close() from the main thread, it won't stop doing the recv. It will only stop if I first send something through telnet, then it will fail doing further sends and recvs. My code look like this: # Echo server program import socket from threading import Thread import time class ClientThread(Thread): def __init__(self, clientSocket): Thread.__init__(self) self.clientSocket = clientSocket def run(self): while 1: try: # It will hang here, even if I do close on the socket data = self.clientSocket.recv(1024) print "Got data: ", data self.clientSocket.send(data) except: break self.clientSocket.close() HOST = '' PORT = 6000 serverSocket = socket.socket(socket.AF_INET, socket.SOCK_STREAM) serverSocket.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1) serverSocket.bind((HOST, PORT)) serverSocket.listen(1) clientSocket, addr = serverSocket.accept() print 'Got a new connection from: ', addr clientThread = ClientThread(clientSocket) clientThread.start() time.sleep(1) # This won't make the recv in the clientThread to stop immediately, # nor will it generate an exception clientSocket.close()

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• Improving the performance of XSL

  - by Rachel

  I am using the below XSL 2.0 code to find the ids of the text nodes that contains the list of indices that i give as input. the code works perfectly but in terms for performance it is taking a long time for huge files. Even for huge files if the index values are small then the result is quick in few ms. I am using saxon9he Java processor to execute the XSL. <xsl:variable name="insert-data" as="element(data)*"> <xsl:for-each-group select="doc($insert-file)/insert-data/data" group-by="xsd:integer(@index)"> <xsl:sort select="current-grouping-key()"/> <data index="{current-grouping-key()}" text-id="{generate-id( $main-root/descendant::text()[ sum((preceding::text(), .)/string-length(.)) ge current-grouping-key() ][1] )}"> <xsl:copy-of select="current-group()/node()"/> </data> </xsl:for-each-group> </xsl:variable> In the above solution if the index value is too huge say 270962 then the time taken for the XSL to execute is 83427ms. In huge files if the index value is huge say 4605415, 4605431 it takes several minutes to execute. Seems the computation of the variable "insert-data" takes time though it is a global variable and computed only once. Should the XSL be addessed or the processor? How can i improve the performance of the XSL.

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• Logs overwritten in CruiseCControl.NET when there is multiple MSBuild Tasks.

  - by James Poulose

  I have two MSBuild tasks in my CC.NET config. In the end of the execution, i can see two blocks of warnings/errors in the log and published email. But the problem is that the contents of both the blocks are the same and that is from the second MSBuild task!! In another way, the second MSBuild task overwrites the first log, and then creates another one for itself effectively creating two exactly identical block!!! Do anybody have any thoughts on this? I am happy to provide more information if you require about the environment and configuration. Thanks, James Poulose

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• date comparisons in Rails

  - by aressidi

  Hi there, I'm having trouble with a date comparison in a named scope. I'm trying to determine if an event is current based on its start and end date. Here's the named scope I'm using which kind of works, though not for events that have the same start and end date. named_scope :date_current, :conditions => ["Date(start_date) <= ? AND Date(end_date) >= ?", Time.now, Time.now] This returns the following record, though it should return two records, not one... >> Event.date_current => [#<Event id: 2161, start_date: "2010-02-15 00:00:00", end_date: "2010-02-21 00:00:00", ...] What it's not returning is this as well >> Event.find(:last) => #<Event id: 2671, start_date: "2010-02-16 00:00:00", end_date: "2010-02-16 00:00:00", ...> The server time seems to be in UTC and I presume that the entries are being stored in the DB in UTC. Any ideas as to what I'm doing wrong or what to try? Thanks!

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• [php] Cookies only changing value every two page refreshes?

  - by Gazillion

  Hello, I'm trying to implement some pixel tracking where I will save certain values in a cookie to then forward users to another page. If users purchase a product after being forwarded to the online store by us the store adds an image tag in the page with our php script included. With the values set in the cookie we would like to track conversions. I understand this tracking technique has some limitations (like if a user has cookies turned off or if they do not load images but that's the direction my client wanted to go in). The problem I'm having is that the cookie's behaviour is extremely... random. I've been trying to track their values (with a var_dump so I don't have to wait for a page reload to view the cookie's value) but it seems the value for one field only gets refreshed every two page reloads. setcookie("tracking[cn]", $cn, time()+3600*24*7,'/','mydomain.com'); setcookie("tracking[t]", $t, time()+3600*24*7,'/','mydomain.com'); setcookie("tracking[kid]", $kid, time()+3600*24*7,'/','mydomain.com'); redirectTo($redirect_url); the values of cn, t are fine but for some reason kid is always wrong (having taken the value of the previous kid) Any help would be extremely appreciated I've been at this all evening! :)

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• Passing user context to from impersonated thread to outproc COM object

  - by Thumbeti

  Hi, I am writing a CPP program on windows 2k3 where i want to achieve the following thing. Pass the user context from the impersonated thread to a outproc COM component. Steps what i m trying in details are: 1) Start an execution of exe with user USR1 2) Impersonate the current thread with USR2 3) Initiate a API on outproc COM object. And this COM object should run with USR2 What is happening: on 3rd step, COM object is getting started with USR1 only. Can anybody help me in passing the user context to COM object. Thanks in advance, Thumbeti

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• Setting a breakpoint in a T4 template

  - by Dave Swersky

  I'm trying to debug the execution of a T4 template in Visual Studio 2008. All the information I'm finding on debugging T4 templates in Visual Studio 2008 say that you can set a breakpoint (red dot) in the template as if it were a regular code file. I have the Clarius T4 code highlighter installed, so my T4 template is colored, but I can't set a breakpoint. When I click in the margin nothing happens. I've tried Debugger.Break(), and it launches a new instance of VS.NET, but it can't load the code from my template. I get a dialog that says "There is no source code available for the current location." This happens if I have the same project loaded in the another instance of if I spin up a new instance. What gives?

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• Are there solutions for streamlining the update of legacy code in multiple places?

  - by ccomet

  I'm working in some old code which was originally designed for handling two different kinds of files. I was recently tasked with adding a new kind of file to this code. Most of my problems were solved by filling out an extensive XML file with a new entry that handled everything from what lists were named to how the file is written in plural lower case. But this ended up being insufficient, as there were maybe 50 different places in 24 different code files where I had to update hardcoded switch-statements that only branched for the original two file types. Unfortunately there is no consistency in this; there are methods which operate half from the XML file, and half off of hardcode. Some of the files which look like they would operate off of the XML file don't, and some that I would expect that I'd need to update the hardcode don't need it. So the only way to find the majority of these is to run through testing the whole system when only part of it is operational, finding that one step to fix (when I'm lucky that error logging actually tells me what is going on), and then running the whole thing again. This wastes time testing the parts of the code which are already confirmed to work, time better spent testing the new parts I have to add on top of it all. It's a hassle and a half, and to my luck I can expect that I will have to add yet another new kind of file in the near future. Are there any solutions out there which can aid in this kind of endeavour? Something which I can input some parameters of current features, document what points in a whole code project actually need to be updated, and run something nice the next time I need to add a new feature to the code. It needn't even be fully automated, something that'll help me navigate straight to the specific points in everything and maybe even record what kind of parameters need to be loaded. Doubt it matters specifically, but the code is comprised of ASP.NET pages, some ASP.NET controls, hundreds of C# code files, and a handful of additional XML files. It's all currently in a couple big Visual Studio 2008 projects.

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• Parse JSON into a ListView friendly output

  - by Thomas McDonald

  So I have this JSON, which then my activity retrieves to a string: {"popular": {"authors_last_month": [ { "url":"http://activeden.net/user/OXYLUS", "item":"OXYLUS", "sales":"1148", "image":"http://s3.envato.com/files/15599.jpg" }, { "url":"http://activeden.net/user/digitalscience", "item":"digitalscience", "sales":"681", "image":"http://s3.envato.com/files/232005.jpg" } { ... } ], "items_last_week": [ { "cost":"4.00", "thumbnail":"http://s3.envato.com/files/227943.jpg", "url":"http://activeden.net/item/christmas-decoration-balls/75682", "sales":"43", "item":"Christmas Decoration Balls", "rating":"3", "id":"75682" }, { "cost":"30.00", "thumbnail":"http://s3.envato.com/files/226221.jpg", "url":"http://activeden.net/item/xml-flip-book-as3/63869", "sales":"27", "item":"XML Flip Book / AS3", "rating":"5", "id":"63869" }, { ... }], "items_last_three_months": [ { "cost":"5.00", "thumbnail":"http://s3.envato.com/files/195638.jpg", "url":"http://activeden.net/item/image-logo-shiner-effect/55085", "sales":"641", "item":"image logo shiner effect", "rating":"5", "id":"55085" }, { "cost":"15.00", "thumbnail":"http://s3.envato.com/files/180749.png", "url":"http://activeden.net/item/banner-rotator-with-auto-delay-time/22243", "sales":"533", "item":"BANNER ROTATOR with Auto Delay Time", "rating":"5", "id":"22243"}, { ... }] } } It can be accessed here as well, although it because it's quite a long string, I've trimmed the above down to display what is needed. Basically, I want to be able to access the items from "items_last_week" and create a list of them - originally my plan was to have the 'thumbnail' on the left with the 'item' next to it, but from playing around with the SDK today it appears too difficult or impossible to achieve this, so I would be more than happy with just having the 'item' data from 'items_last_week' in the list. Coming from php I'm struggling to use any of the JSON libraries which are available to Java, as it appears to be much more than a line of code which I will need to deserialize (I think that's the right word) the JSON, and they all appear to require some form of additional class, apart from the JSONArray/JSONObject script I have which doesn't like the fact that items_last_week is nested (again, I think that's the JSON terminology) and takes an awful long time to run on the Android emulator. So, in effect, I need a (preferably simple) way to pass the items_last_week data to a ListView. I understand I will need a custom adapter which I can probably get my head around but I cannot understand, no matter how much of the day I've just spent trying to figure it out, how to access certain parts of a JSON string..

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• Do I need to Dispose to deregister events?

  - by Sean

  Say I have two classes, and neither of them are GUI components. Class A is a short lived object that registers for an event declared by a long lived object B. For example public A(B b) { b.ChangeEvent += OnChangeEvent; } If A never deregisters from B's event, will A never be garbage collected? Does A need a Dispose method just to deregister from B's event? There is also a related second question. If A and B should both live for the entire execution time of the application, does A need to deregister?

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• Project Management and Scheduling Techniques

  - by Alec Smart

  Hello, I know this is probably the nth project management question. But am trying to move my team onto a more robust project management technique. Am wondering what is the best technique to use? I know that probably no technique is best, but which are the most popular techniques? Poker planning? Evidence Based Scheduling? COCOMO? Agile? Scrum? XP? Which one to use? Also, suppose I use EBS, wouldn't it be too time consuming to break down every single activity into fine grained tasks? E.g. "Design" is a goal, what kind of fine-grained tasks will I have under it? Is this is a waste of time i.e. dividing work into so many micro parts. Usually when I give my programmers a task, I follow up every week, and they complete quite a lot of the task assigned to them (the tasks are very broad e.g. X module). Is EBS worth it? Are there any white-papers on it so that I can implement it on my own? (instead of using Fogbugz) Most of my projects are web-based projects. Thank you for your time.

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• Zend_Date and Zend Locale; can't get it to work ><

  - by Rick de Graaf

  Loving Zend Framework, hating Zend_Date... I'm buidling an app where one of the functions is to track the time one spends on a certain task. This works great. My previous question was my incapability to get the sum of all the timestamps (time spent on each task). Well that works as a charm, but when I echo this value, it adds one hour. Using gmdate() (just for checking) and the value turns out exactly as it's supposed to. I thought to solve this problem easeliy with Zend_Local, but I can't get the damn thing to work! This is my bootstrap code: protected function _initLocale() { $locale = new Zend_Locale('nl_NL'); $locale->setLocale($locale); Zend_Registry::set('Zend_Locale', $locale); } This is the code in my view file: $date = new Zend_Date($this->timequery, null, $locale); echo $date->toString(Zend_Date::HOUR.':'.Zend_Date::MINUTE.':'.Zend_Date::SECOND); The timestamp I'm processing is: 2632 which equals 00:43:52. The output I get is: 01:43:52 I know the extra hour comes from the time difference, but I can seem to solve this with Zend_Local and Zend_Date.

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• Automatic exit from bash shell script on error

  - by radman

  Hi, I've been writing some shell script and I would find it useful if there was the ability to halt the execution of said shell script if any of the commands failed. See below for an example: #!/bin/bash cd some_dir ./configure --some-flags make make install So in this case if the script can't change to the indicated directory then it would certainly not want to do a ./configure afterward it fails. Now I'm well aware that I could have an if check for each command (which I think is a hopeless solution), but is there a global setting to make the script exit if one of the commands fails?

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• Select a certain amount of checkbox arrays on the page

  - by Joris Tobebech

  Hi guys, so i wrote a function to select a certain amount of checkboxes on the page, the number retrieves fine when i message box it but no checkboxes are checked. here is my function function checkAmount(number) { alert(number); var boxes = document.getElementsByTagName("input"); for (var i = 0; i < number; i++) { if (boxes[i].name == "vote[]") { boxes[i].checked = true; } } } and here is my execution code OnClick="checkAmount(document.getElementById(\'ammount\').value)"

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• Write Null/Nothing value with Databinding

  - by clawson

  I have extended a MaskedTextBox component to add some functionality. The text property of the extended MaskedTextBox is bound to a DateTime? property and the format of binding is set to a time format of "HH:mm:ss" (i.e. 24hr time). So that this masked text box will capture the display a time. The extra functionality I have added is to make the component readonly unless the component is double clicked or the enter button is pressed (the back color of the control helps to inform the users if the component is locked/readonly or not). When the enter button is pressed I also suspend the bindings so that bound data is updated the users input won't be lost. The information is then written back to the value and databindings resumed when the user presses the enter key again. This all works fine up to here, with values written and displayed as would be expected. However, I also want to write the null or nothing value to the DateTime? property if the user hasn't entered any text (or invalid text but let's just stick with no text) when enter key is pressed to submit the new value. Unlike with other valid entries in the MaskedTextBox, with no text entered when i execute: Me.DataBindings("Text").WriteValue() (when 'locking' the MaskedTextBox) it then branches to the bound properties Get method as I step into each line of code in the debugger (as opposed to the Set method with other valid entries) How can I write this null/nothing/"" value to the DateTime? property when no text "" is entered into the MaskedTextBox? Thanks for the help!

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• Socket ping-pong performance

  - by Kamil_H

  I have written two simple programs (tried it in C++ and C#). This is pseudo code: -------- Client --------------- for(int i = 0; i < 200.000; i++) { socket_send("ping") socket_receive(buff) } --------- Server ------------- while(1) { socket_receive(buff) socket_send("pong") } I tried it on Windows. Execution time of client is about 45 seconds. Can somebody explain me why this takes so long? I understand that if there were real network connection between client and server the time of one 'ping-pong' would be: generate_ping + send_via_network + generate_pong + send_via_network but here everything is done in 'local' mode. Is there any way to make this inter process ping-pong faster using network sockets (I'm not asking about shared memory for example :) )

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• [C++]Advantage of using a static member function instead of an equivalent non-static member function

  - by jonathanasdf

  I was wondering whether there's any advantages to using a static member function when there is a non-static equivalent. Will it result in faster execution (because of not having to care about all of the member variables), or maybe less use of memory (because of not being included in all instances)? Basically, the function I'm looking at is an utility function to rotate an integer array representing pixel colours an arbitrary number of degrees around an arbitrary centre point. It is placed in my abstract Bullet base class, since only the bullets will be using it and I didn't want the overhead of calling it in some utility class. It's a bit too long and used in every single derived bullet class, making it probably not a good idea to inline. How would you suggest I define this function? As a static member function of Bullet, of a non-static member function of Bullet, or maybe not as a member of Bullet but defined outside of the class in Bullet.h? What are the advantages and disadvantages of each?

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• What can be used instead of Datatable in LINQ

  - by Kabi

  I have a SQL query that returns a Datatable: var routesTable = _dbhelper.Select("SELECT [RouteId],[UserId],[SourceName],[CreationTime] FROM [Routes] WHERE UserId=@UserId AND RouteId=@RouteId", inputParams); and then we can work with Datatable object of routesTable if (routesTable.Rows.Count == 1) { result = new Route(routeId) { Name = (string)routesTable.Rows[0]["SourceName"], Time = routesTable.Rows[0]["CreationTime"] is DBNull ? new DateTime() : Convert.ToDateTime(routesTable.Rows[0]["CreationTime"]) }; result.TrackPoints = GetTrackPointsForRoute(routeId); } I want to change this code to linq but I don't know how can I simulate Datatable in LINQ ,I wrote this part: Route result = null; aspnetdbDataContext aspdb = new aspnetdbDataContext(); var Result = from r in aspdb.RouteLinqs where r.UserId == userId && r.RouteId==routeId select r; .... but I don't know how can I change this part: if (routesTable.Rows.Count == 1) { result = new Route(routeId) { Name = (string)routesTable.Rows[0]["SourceName"], Time = routesTable.Rows[0]["CreationTime"] is DBNull ? new DateTime() : Convert.ToDateTime(routesTable.Rows[0]["CreationTime"]) }; would you please tell me how can I do this? EDIT here you can see the whole block of code in original public Route GetById(int routeId, Guid userId) { Route result = null; var inputParams = new Dictionary<string, object> { {"UserId", userId}, {"RouteId", routeId} }; var routesTable = _dbhelper.Select("SELECT [RouteId],[UserId],[SourceName],[CreationTime] FROM [Routes] WHERE UserId=@UserId AND RouteId=@RouteId", inputParams); if (routesTable.Rows.Count == 1) { result = new Route(routeId) { Name = (string)routesTable.Rows[0]["SourceName"], Time = routesTable.Rows[0]["CreationTime"] is DBNull ? new DateTime() : Convert.ToDateTime(routesTable.Rows[0]["CreationTime"]) }; result.TrackPoints = GetTrackPointsForRoute(routeId); } return result; }

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• Looking for Bugtracker with specific features

  - by Thorsten Dittmar

  Hi, we're looking into bugtracking systems at our firm. We're quite small (4 developers only). On the other hand we have quite a large number of customers we develop individual software for. Most software is built explicitly for one customer, apart from two or three standard tools we ship. To make support easier for us (and to avoid being interrupted by phone calls all the time) we're looking for a bugtracker that must support a specific set of features. We want the customers to report bugs/feature/change requests themselves and be notified about these reports by email. Then we'd like to track what we've done and how much time it took, notifying the customer about that per email (private notes for just us must be possible). At the end of the month we'd like to bill all closed reports according to the time it took to solve/implement them. The following must be possible: It must have a web based interface where the users must log in with credentials we provide. The users must not be able to create accounts themselves/we must be able to turn off such a feature. We must be able to configure projects and assign customer logins to these projects. The customers must only see projects they are assigned to, not any other projects. Also, customers must not "see" other customers. We would name the projects, so that standard tools are listed as separate projects for each customer. A monthly report must be available that we can use to get information about the requests we worked on per customer. I'd like to introduce some standard product like Mantis (I've played with that a little, but didn't quite figure out whether it provides all the features I listed above). The product should be Open Source and work on a XAMPP Windows Server 2003 environment. Does anybody have any good suggestions?

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• Access violation exception from Delphi's Supports -> QueryInterface

  - by Sharon

  Hi, I have the following piece of code: for i := 0 to FControlList.Count - 1 do if Supports(IMyControl(FControlList[i]), IMyControlEx) then begin MyControlEx := IMyControl(FControlList[i]) as IMyControlEx; MyControlEx.DoYourMagic(Self, SomeData); end; This code is called many times during my application execution, but in some specific cases it fails inside the Supports() method. And more specifically - it seems to fall inside the QueryInterface() call within the Supports() method. I checked that FControlList is not nil and FControlList[i] is not nil and it still happens. Any idea will be appreciated!!!

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• What's the best way to measure and track performance over various calls at runtime?

  - by bitcruncher

  Hello. I'm trying to optimize the performance of my code, but I'm not familiar with xcode's debuggers or debuggers in general. Is it possible to track the execution time and frequency of calls being made at runtime? Imagine a chain of events with some recursive calls over a fraction of a second. What's the best way to track where the CPU spends most of its time? Many thanks. Edit: Maybe this is better asked by saying, how do I use the xcode debug tools to do a stack trace?

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• Client Web Browser Behavior When Handling 301 Redirect

  - by Jon Swanson

  The RFC seems to suggest that the client should permanently cache the response: http://www.w3.org/Protocols/rfc2616/rfc2616-sec10.html 10.3.2 301 Moved Permanently The requested resource has been assigned a new permanent URI and any future references to this resource SHOULD use one of the returned URIs. Clients with link editing capabilities ought to automatically re-link references to the Request-URI to one or more of the new references returned by the server, where possible. This response is cacheable unless indicated otherwise. The new permanent URI SHOULD be given by the Location field in the response. Unless the request method was HEAD, the entity of the response SHOULD contain a short hypertext note with a hyperlink to the new URI(s). If the 301 status code is received in response to a request other than GET or HEAD, the user agent MUST NOT automatically redirect the request unless it can be confirmed by the user, since this might change the conditions under which the request was issued. Note: When automatically redirecting a POST request after receiving a 301 status code, some existing HTTP/1.0 user agents will erroneously change it into a GET request. I'm having a hard time finding concrete browser documentation for any major browser that states how they handle these. I've started digging through the source code of firefox, but quickly got lost. Is the following scenario true for which (if any) browsers, and is there definitive documentation for either Firefox or IE that states as much?: First Time Around: 1.1: User enters link to site A, or clicks on a link directed at Site A 1.2: Browser interprets link at Site A, first time, no cache. Sends GET to Site A. 1.2: Site A responds with 301 Redirect to Site B 1.3: Browser sends GET to Site B. Any Subsequent Times Around: 2.2: User clicks on a link directed at Site A 2.2: Browser sees that, due to a past 301 redirect, Site A should now be Site B. 2.3: Without initiating any request whatsoever at Site A, browser initiates GET at Site B.

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• Strongly Typed Controls in .NET

  - by Tigraine

  I am working on a Windows Forms app for quite some time now, and I really find myself doing more typecasts in the GUI code than I ever did in my underlying business code. What I mean becomes apparent if you watch the ComboBox control that accepts some vague "object" as it's item. Then you go off and may display some DisplayMember and a ValueMember and so on. If I want to retrieve that value later I need to typecast my object back to what it was. Like with strings getting the value takes string value = (string)combobox1.SelectedItem; Since there are generics in the Framework for quite some time now, I still wonder why in the Hell not one control from the standard toolbox is generic. I also find myself using the .Tag property on ListViewItems all the time to keep the displayed domain object. But everytime I need to access that object I then need another typecast. Why cant I just create a ComboBox or ListView with items of type ListViewItem Am I missing something here or is this just another example of not perfectly well thought through controls?

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• Java Random Slowdowns on Mac OS cont'd

  - by javajustice

  I asked this question a few weeks ago, but I'm still having the problem and I have some new hints. The original question is here: http://stackoverflow.com/questions/1651887/java-random-slowdowns-on-mac-os Basically, I have a java application that splits a job into independent pieces and runs them in separate threads. The threads have no synchronization or shared memory items. The only resources they do share are data files on the hard disk, with each thread having an open file channel. Most of the time it runs very fast, but occasionally it will run very slow for no apparent reason. If I attach a CPU profiler to it, then it will start running quickly again. If I take a CPU snapshot, it says its spending most of its time in "self time" in a function that doesn't do anything except check a few (unshared unsynchronized) booleans. I don't know how this could be accurate because 1, it makes no sense, and 2, attaching the profiler seems to knock the threads out of whatever mode they're in and fix the problem. Also, regardless of whether it runs fast or slow, it always finishes and gives the same output, and it never dips in total cpu usage (in this case ~1500%), implying that the threads aren't getting blocked. I have tried different garbage collectors, different sizings the parts of the memory space, writing data output to non-raid drives, and putting all data output in threads separate the main worker threads. Does anyone have any idea what kind of problem this could be? Could it be the operating system (OS X 10.6.2) ? I have not been able to duplicate it on a windows machine, but I don't have one with a similar hardware configuration.

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