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  • SQL Monitoring Overview

    - by user45237
    Hi I currently loook after 20 odd databases in SQL server 2005 and need a tool for monitoring the performance and keep me informed if a database is running slow. Is there anything I can run within Managment studio of any other good third party tool (Pref free) that can do the job. Thanks

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  • Why is 'virtual' optional for overridden methods in derived classes?

    - by squelart
    When a method is declared as virtual in a class, its overrides in derived classes are automatically considered virtual as well, and the C++ language makes this keyword virtual optional in this case: class Base { virtual void f(); }; class Derived : public Base { void f(); // 'virtual' is optional but implied. }; My question is: What is the rationale for making virtual optional? I know that it is not absolutely necessary for the compiler to be told that, but I would think that developers would benefit if such a constraint was enforced by the compiler. E.g., sometimes when I read others' code I wonder if a method is virtual and I have to track down its superclasses to determine that. And some coding standards (Google) make it a 'must' to put the virtual keyword in all subclasses.

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  • Is it perfectly safe to install grub bootloader on regular partition?

    - by Flint
    One of the methods to do dual booting Windows with Linux OS is by installing grub boot loader onto Linux partition so you can retain Windows boot loader and let Windows handles the dual booting process. What's the odd that grub bootloader could partially overwrite the data at the beginning of the Linux partition and corrupt the file? Does grub actually check if there's a data at the beginning of the partition and move it to other location on the partition before writing its bootloader?

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  • Time lag between PreRenderComplete and SaveState

    - by KPK
    We are tracing our ASP.NET application and find that for one of our pages we see that there is a time lag of around 2.5 secs from the time PreRenderComplete Ends to SaveState Begins. Below is a part of log aspx.page End PreRender 9.123185387 0.184541 aspx.page Begin PreRenderComplete 9.123277718 0.000092 aspx.page End PreRenderComplete 9.123666575 0.000389 aspx.page Begin SaveState 11.77441916 2.650753 aspx.page End SaveState 11.77457158 0.000152 aspx.page Begin SaveStateComplete 11.77459695 0.000025 aspx.page End SaveStateComplete 11.77461284 0.000016 aspx.page Begin Render 11.77462541 0.000013 aspx.page End Render 15.10157813 3.326953 we are trying to understand if there is any rationale behind this. Pls help me understand this. Thanks in Advance

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  • Can create and delete files through samba, but not modify?

    - by PoppySeeds
    I'm connecting from Windows 7 to Ubuntu Server 10.04 using samba. I can create new files in the share, delete those files, but if I try to edit a file, and then save it, I get an access denied. My User in Windows is the same as the one I'm connecting as and as setup in Ubuntu. This is very odd. I also have trouble copying files to Ubuntu as well. It errors but lets me copy them anyway.

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  • Recovered folders from Camera show as JPEG files and can can't be viewed.

    - by user642111
    I have recovered a CCTV camera hard disk after a crash and have managed to get most of the data using EasyRecovery Pro. The problem is now that all the data that I have recovered appear like File09.JPG with and image icon in windows XP, but the files can't be viewed in any JPEG viewer software. I suspect that the .JPG files are indeed folders, but I can't force windows XP the change the file type. Very Odd. Any help is appreciated. Thanks, Hoo

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  • Comparing Design Patterns

    - by Lijo
    Hi, I am learning design patterns using C#. One of the challenges that I am facing is that they look similar. Could you please help me to distinguish them – basically when to use them? - Why not the other? Bridge and Strategy State and Strategy Façade and Strategy Composite and Strategy I understand that there are lots of resources available in the web. However they does not treat this special question. [Note: I am looking for implementation examples and rationale behind the selection; not mere explanations] It would be great if you are taking examples from any of the following 1) E-Commerce 2) Payroll system 3) Banking 4) Retailing Thanks for your understanding.. Thanks Lijo

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  • When RAID 10 is SLOWER than RAID 1, why?

    - by Paul
    We have a Dell 2950 with PERC and 14 external SAS 15K 73GB drives. An Oracle database job takes 3 hours to run with the drives set as hardware RAID 10 (striped across 7 mirrored pairs). The same job with the drives in RAID 1 takes only 1 hour. OS is Win 2008 R2 I think. Before we change the RAID level (with considerable downtime) on the production box, does anyone know why we're seeing this odd result, and if there's a better way to fix it?

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  • Small Business Server 2011 and Remote access to documents

    - by Tim Long
    Assume I'm working away from the office; its a hotel computer Windows 7, Office 2010 and fast - so the best possible conditions. Using Companyweb - Every time I open a document, I have to go through the logon process - seems odd to have to do that. Is this a 'by design' feature or is something wrong with my configuration? When I do open the documents, are they being stored somewhere locally and should I be looking to delete on this computer - or are they in a temporary file?

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  • Python - Why ever use SHA1 when SHA512 is more secure?

    - by orokusaki
    I don't mean for this to be a debate, but I'm trying to understand the technical rationale behind why so many apps use SHA1, when SHA512 is more secure. Perhaps it's simply for backwards compatibility. Besides the obvious larger size (128 chars vs 40), or slight speed differences, is there any other reason why folks use the former? Also, SHA-1 I believe was first cracked by a VCR's processor years ago. Has anyone cracked 512 yet (perhaps with a leaf blower), or is it still safe to use without salting?

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  • SFTP "Could not connect to server error"

    - by Ash
    I'm having problems connecting to my server via SFTP. I can SSH in to the system perfectly fine, but for some odd reason, i'm not able to SFTP (which I used to be able to). I have cleared ALL my iptables rules iptables -F still no access. I have removed the sub system (to allow FULL access) still no access. I can't for the life of me figure out what the problem is. Thus is therefore making a solution impossible.

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  • What all is there to know about ping while troubleshooting an internet connection?

    - by tMJ
    What all is there to know about ping and the IP address to ping while troubleshooting/diagnosing a problem in the internet connection? For example: I run the command ping 192.168.1.1 -t in the command prompt, and if there is no reply I get something is odd, but I don't understand what is and where it is. I am looking for a complete list (okay, as many as you got), of IP address to ping while troubleshooting my network connection, and an insight into what the status message returned by them implies.

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  • Is it acceptable to design my GLSurfaceView as a main control class?

    - by Omega
    I'm trying to structure a game I'm making in Android so that I have a sound, flexible design. Right now I'm looking at where I can tie my games rules engine and graphics engine together and what should be in between them. At a glance, I've been eying my implementation of GLSurfaceView, where various screen events are captured. My rationale would be to create an instance of my game engine and graphics engine here and receive events and state changes to trigger updates of either where applicable. Further to this, in the future, the GLSurfaceView implementation could also store stubs for players during a network game and implementations of computer opponents and dispatch them appropriately. Does this seem like a sensible design? Are there any kinds of improvements I can make? Thanks for any input!

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  • Using try vs if in python

    - by artdanil
    Is there a rationale to decide which one of try or if constructs to use, when testing variable to have a value? For example, there is a function that returns either a list or doesn't return a value. I want to check result before processing it. Which of the following would be more preferable and why? result = function(); if (result): for r in result: #process items or result = function(); try: for r in result: #process items except TypeError: pass; Related discussion: Checking for member existence in Python

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  • Deleting a element from a vector of pointers in C++.

    - by Kranar
    I remember hearing that the following code is not C++ compliant and was hoping someone with much more C++ legalese than me would be able to confirm or deny it. std::vector<int*> intList; intList.push_back(new int(2)); intList.push_back(new int(10)); intList.push_back(new int(17)); for(std::vector<int*>::iterator i = intList.begin(); i != intList.end(); ++i) { delete *i; } intList.clear() The rationale was that it is illegal for a vector to contain pointers to invalid memory. Now obviously my example will compile and it will even work on all compilers I know of, but is it standard compliant C++ or am I supposed to do the following, which I was told is in fact the standard compliant approach: while(!intList.empty()) { int* element = intList.back(); intList.pop_back(); delete element; }

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  • django - where to clean extra whitespace from form field inputs?

    - by Westerley
    I've just discovered that Django doesn't automatically strip out extra whitespace from form field inputs, and I think I understand the rationale ('frameworks shouldn't be altering user input'). I think I know how to remove the excess whitespace using python's re: #data = re.sub('\A\s+|\s+\Z', '', data) data = data.strip() data = re.sub('\s+', ' ', data) The question is where should I do this? Presumably this should happen in one of the form's clean stages, but which one? Ideally, I would like to clean all my fields of extra whitespace. If it should be done in the clean_field() method, that would mean I would have to have a lot of clean_field() methods that basically do the same thing, which seems like a lot of repetition. If not the form's cleaning stages, then perhaps in the model that the form is based on? Thanks for your help! W.

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  • Determining where a function is defined in C#?

    - by templatetypedef
    Hey all - I am a complete novice at C# (I've never used it before) and recently needed to look over some code written in it. I spent the longest time trying to track down a nonexistent method in a class that didn't seem to be defined anywhere in the class that was using it. I later found out it was an "extension method," which I gather is a method grafted onto another class by some source. I completely understand the rationale behind this language feature and actually think it's quite nice. However, as someone without much experience in the language, it makes it harder to look up unfamiliar methods, since the method in question could be defined anywhere. My question is this: given an unfamiliar method call in C#, what's the best way for me to look up more info on it, given that it could be an extension method defined in an entirely separate class? Thanks!

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  • HttpWebRequest and Ignoring SSL Certificate Errors

    - by Rick Strahl
    Man I can't believe this. I'm still mucking around with OFX servers and it drives me absolutely crazy how some these servers are just so unbelievably misconfigured. I've recently hit three different 3 major brokerages which fail HTTP validation with bad or corrupt certificates at least according to the .NET WebRequest class. What's somewhat odd here though is that WinInet seems to find no issue with these servers - it's only .NET's Http client that's ultra finicky. So the question then becomes how do you tell HttpWebRequest to ignore certificate errors? In WinInet there used to be a host of flags to do this, but it's not quite so easy with WebRequest. Basically you need to configure the CertificatePolicy on the ServicePointManager by creating a custom policy. Not exactly trivial. Here's the code to hook it up: public bool CreateWebRequestObject(string Url) {    try     {        this.WebRequest =  (HttpWebRequest) System.Net.WebRequest.Create(Url);         if (this.IgnoreCertificateErrors)            ServicePointManager.CertificatePolicy = delegate { return true; };}One thing to watch out for is that this an application global setting. There's one global ServicePointManager and once you set this value any subsequent requests will inherit this policy as well, which may or may not be what you want. So it's probably a good idea to set the policy when the app starts and leave it be - otherwise you may run into odd behavior in some situations especially in multi-thread situations.Another way to deal with this is in you application .config file. Normal 0 false false false EN-US X-NONE X-NONE /* Style Definitions */ table.MsoNormalTable {mso-style-name:"Table Normal"; mso-tstyle-rowband-size:0; mso-tstyle-colband-size:0; mso-style-noshow:yes; mso-style-priority:99; mso-style-parent:""; mso-padding-alt:0in 5.4pt 0in 5.4pt; mso-para-margin-top:0in; mso-para-margin-right:0in; mso-para-margin-bottom:10.0pt; mso-para-margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri","sans-serif"; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;} <configuration>   <system.net>     <settings>       <servicePointManager           checkCertificateName="false"           checkCertificateRevocationList="false"                />     </settings>   </system.net> </configuration> This seems to work most of the time, although I've seen some situations where it doesn't, but where the code implementation works which is frustrating. The .config settings aren't as inclusive as the programmatic code that can ignore any and all cert errors - shrug. Anyway, the code approach got me past the stopper issue. It still amazes me that theses OFX servers even require this. After all this is financial data we're talking about here. The last thing I want to do is disable extra checks on the certificates. Well I guess I shouldn't be surprised - these are the same companies that apparently don't believe in XML enough to generate valid XML (or even valid SGML for that matter)...© Rick Strahl, West Wind Technologies, 2005-2011Posted in .NET  CSharp  HTTP  

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  • How to install Juniper VPN on Ubuntu 14.04 LTS?

    - by Max Ricardo Mercurio Ribeiro
    Could you please help me ? On my old Ubuntu 13.10 I was able to run Juniper VPN (on Firefox only) using a workaround which requires you to install the missing 32libs and IcedTea (32bits). However, I recently upgraded from Ubuntu 13.10 to 14.04 (both 64 bits) and my Juniper VPN does not work anymore because it fails during startup showing the following message: "Please ensure that necessary 32 bit libraries are installed. For more details, refer KB article KB25230" "Setup failed. Please install 32 bit Java and update alternatives links using update-alternatives command. For more details, refer KB article KB25230" For some odd reason, it seems the 14.04 upgrade do not work anymore with the openjdk-7:386 and consequently the Juniper VPN as well. Any ideas ? Thanks

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  • What is the best email address for a personal website with my name as the .com domain name?

    - by Travis Pflanz
    I convinced one of my creative friends to finally purchase his own name as a domain name and start a portfolio. It has been years coming, but mission finally accomplished. Now I am helping him build his website. For my own personal website, I registered pflanz.me and my personal website is travis.pflanz.me. My email address is travis AT pflanz.me. I really like this idea for a personal website. I also have travispflanz.com which redirects to travis.pflanz.me, as does pflanz.me (pflanz.com was not available). While I really like this idea, he did not, and only wanted the .com, so his domain is FirstnameLastname.com. One of the main reasons I went the route I did is because I couldn't come up with a suitable @travispflanz.com email address, travis AT travispflanz.com just seems odd, as does me AT travispflanz.com. My question, what are the best personal email addresses to use for personal full-name .com domain names? Thanks!

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  • SmtpClient and Locked File Attachments

    - by Rick Strahl
    Got a note a couple of days ago from a client using one of my generic routines that wraps SmtpClient. Apparently whenever a file has been attached to a message and emailed with SmtpClient the file remains locked after the message has been sent. Oddly this particular issue hasn’t cropped up before for me although these routines are in use in a number of applications I’ve built. The wrapper I use was built mainly to backfit an old pre-.NET 2.0 email client I built using Sockets to avoid the CDO nightmares of the .NET 1.x mail client. The current class retained the same class interface but now internally uses SmtpClient which holds a flat property interface that makes it less verbose to send off email messages. File attachments in this interface are handled by providing a comma delimited list for files in an Attachments string property which is then collected along with the other flat property settings and eventually passed on to SmtpClient in the form of a MailMessage structure. The jist of the code is something like this: /// <summary> /// Fully self contained mail sending method. Sends an email message by connecting /// and disconnecting from the email server. /// </summary> /// <returns>true or false</returns> public bool SendMail() { if (!this.Connect()) return false; try { // Create and configure the message MailMessage msg = this.GetMessage(); smtp.Send(msg); this.OnSendComplete(this); } catch (Exception ex) { string msg = ex.Message; if (ex.InnerException != null) msg = ex.InnerException.Message; this.SetError(msg); this.OnSendError(this); return false; } finally { // close connection and clear out headers // SmtpClient instance nulled out this.Close(); } return true; } /// <summary> /// Configures the message interface /// </summary> /// <param name="msg"></param> protected virtual MailMessage GetMessage() { MailMessage msg = new MailMessage(); msg.Body = this.Message; msg.Subject = this.Subject; msg.From = new MailAddress(this.SenderEmail, this.SenderName); if (!string.IsNullOrEmpty(this.ReplyTo)) msg.ReplyTo = new MailAddress(this.ReplyTo); // Send all the different recipients this.AssignMailAddresses(msg.To, this.Recipient); this.AssignMailAddresses(msg.CC, this.CC); this.AssignMailAddresses(msg.Bcc, this.BCC); if (!string.IsNullOrEmpty(this.Attachments)) { string[] files = this.Attachments.Split(new char[2] { ',', ';' }, StringSplitOptions.RemoveEmptyEntries); foreach (string file in files) { msg.Attachments.Add(new Attachment(file)); } } if (this.ContentType.StartsWith("text/html")) msg.IsBodyHtml = true; else msg.IsBodyHtml = false; msg.BodyEncoding = this.Encoding; … additional code omitted return msg; } Basically this code collects all the property settings of the wrapper object and applies them to the SmtpClient and in GetMessage() to an individual MailMessage properties. Specifically notice that attachment filenames are converted from a comma-delimited string to filenames from which new attachments are created. The code as it’s written however, will cause the problem with file attachments not being released properly. Internally .NET opens up stream handles and reads the files from disk to dump them into the email send stream. The attachments are always sent correctly but the local files are not immediately closed. As you probably guessed the issue is simply that some resources are not automatcially disposed when sending is complete and sure enough the following code change fixes the problem: // Create and configure the message using (MailMessage msg = this.GetMessage()) { smtp.Send(msg); if (this.SendComplete != null) this.OnSendComplete(this); // or use an explicit msg.Dispose() here } The Message object requires an explicit call to Dispose() (or a using() block as I have here) to force the attachment files to get closed. I think this is rather odd behavior for this scenario however. The code I use passes in filenames and my expectation of an API that accepts file names is that it uses the files by opening and streaming them and then closing them when done. Why keep the streams open and require an explicit .Dispose() by the calling code which is bound to lead to unexpected behavior just as my customer ran into? Any API level code should clean up as much as possible and this is clearly not happening here resulting in unexpected behavior. Apparently lots of other folks have run into this before as I found based on a few Twitter comments on this topic. Odd to me too is that SmtpClient() doesn’t implement IDisposable – it’s only the MailMessage (and Attachments) that implement it and require it to clean up for left over resources like open file handles. This means that you couldn’t even use a using() statement around the SmtpClient code to resolve this – instead you’d have to wrap it around the message object which again is rather unexpected. Well, chalk that one up to another small unexpected behavior that wasted a half an hour of my time – hopefully this post will help someone avoid this same half an hour of hunting and searching. Resources: Full code to SmptClientNative (West Wind Web Toolkit Repository) SmtpClient Documentation MSDN © Rick Strahl, West Wind Technologies, 2005-2010Posted in .NET  

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  • TFS 2010 and the missing Area & Iterations (stale data) Issue

    - by andresv
    The symptom is this: you change some area or iteration in a TFS Project, but the change is not reflected (or updated) in VS or any other TFS Client. Well, it happens that TFS now has some clever caching mechanisms that need to be updated when you make a change like this, and those changes are propagated by some scheduled jobs TFS is continuously running in the Application Tier.  So, you you get this behavior, please check (and possibly restart) the "Visual Studio Team Foundation Background Job Agent" service. In my case, this service was logging a very odd "Object Reference Not Set" into the Windows Event Log, and a simple restart fixed it. Hope this is fixed by RTM...   (we are using the RC version). And by the way, if the job agent is broken there are some other things that stops working like email notifications. Best regards, Andrés G Vettori, CTO, VMBC  

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  • So Your Laptop’s Fan Has Stopped Working Then? [Humorous Image]

    - by Asian Angel
    There is such a thing as dust build-up and then there are the odd cases of dust-ball evolution… What is the worst case of dust build-up that you have dealt with? Make sure to share your stories with your fellow readers in the comments! Help, my laptop’s fan is not working! [via Reddit Tech Support Gore] Secure Yourself by Using Two-Step Verification on These 16 Web Services How to Fix a Stuck Pixel on an LCD Monitor How to Factory Reset Your Android Phone or Tablet When It Won’t Boot

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  • ANTS CLR and Memory Profiler In Depth Review (Part 1 of 2 &ndash; CLR Profiler)

    - by ToStringTheory
    One of the things that people might not know about me, is my obsession to make my code as efficient as possible.  Many people might not realize how much of a task or undertaking that this might be, but it is surely a task as monumental as climbing Mount Everest, except this time it is a challenge for the mind…  In trying to make code efficient, there are many different factors that play a part – size of project or solution, tiers, language used, experience and training of the programmer, technologies used, maintainability of the code – the list can go on for quite some time. I spend quite a bit of time when developing trying to determine what is the best way to implement a feature to accomplish the efficiency that I look to achieve.  One program that I have recently come to learn about – Red Gate ANTS Performance (CLR) and Memory profiler gives me tools to accomplish that job more efficiently as well.  In this review, I am going to cover some of the features of the ANTS profiler set by compiling some hideous example code to test against. Notice As a member of the Geeks With Blogs Influencers program, one of the perks is the ability to review products, in exchange for a free license to the program.  I have not let this affect my opinions of the product in any way, and Red Gate nor Geeks With Blogs has tried to influence my opinion regarding this product in any way. Introduction The ANTS Profiler pack provided by Red Gate was something that I had not heard of before receiving an email regarding an offer to review it for a license.  Since I look to make my code efficient, it was a no brainer for me to try it out!  One thing that I have to say took me by surprise is that upon downloading the program and installing it you fill out a form for your usual contact information.  Sure enough within 2 hours, I received an email from a sales representative at Red Gate asking if she could help me to achieve the most out of my trial time so it wouldn’t go to waste.  After replying to her and explaining that I was looking to review its feature set, she put me in contact with someone that setup a demo session to give me a quick rundown of its features via an online meeting.  After having dealt with a massive ordeal with one of my utility companies and their complete lack of customer service, Red Gates friendly and helpful representatives were a breath of fresh air, and something I was thankful for. ANTS CLR Profiler The ANTS CLR profiler is the thing I want to focus on the most in this post, so I am going to dive right in now. Install was simple and took no time at all.  It installed both the profiler for the CLR and Memory, but also visual studio extensions to facilitate the usage of the profilers (click any images for full size images): The Visual Studio menu options (under ANTS menu) Starting the CLR Performance Profiler from the start menu yields this window If you follow the instructions after launching the program from the start menu (Click File > New Profiling Session to start a new project), you are given a dialog with plenty of options for profiling: The New Session dialog.  Lots of options.  One thing I noticed is that the buttons in the lower right were half-covered by the panel of the application.  If I had to guess, I would imagine that this is caused by my DPI settings being set to 125%.  This is a problem I have seen in other applications as well that don’t scale well to different dpi scales. The profiler options give you the ability to profile: .NET Executable ASP.NET web application (hosted in IIS) ASP.NET web application (hosted in IIS express) ASP.NET web application (hosted in Cassini Web Development Server) SharePoint web application (hosted in IIS) Silverlight 4+ application Windows Service COM+ server XBAP (local XAML browser application) Attach to an already running .NET 4 process Choosing each option provides a varying set of other variables/options that one can set including options such as application arguments, operating path, record I/O performance performance counters to record (43 counters in all!), etc…  All in all, they give you the ability to profile many different .Net project types, and make it simple to do so.  In most cases of my using this application, I would be using the built in Visual Studio extensions, as they automatically start a new profiling project in ANTS with the options setup, and start your program, however RedGate has made it easy enough to profile outside of Visual Studio as well. On the flip side of this, as someone who lives most of their work life in Visual Studio, one thing I do wish is that instead of opening an entirely separate application/gui to perform profiling after launching, that instead they would provide a Visual Studio panel with the information, and integrate more of the profiling project information into Visual Studio.  So, now that we have an idea of what options that the profiler gives us, its time to test its abilities and features. Horrendous Example Code – Prime Number Generator One of my interests besides development, is Physics and Math – what I went to college for.  I have especially always been interested in prime numbers, as they are something of a mystery…  So, I decided that I would go ahead and to test the abilities of the profiler, I would write a small program, website, and library to generate prime numbers in the quantity that you ask for.  I am going to start off with some terrible code, and show how I would see the profiler being used as a development tool. First off, the IPrimes interface (all code is downloadable at the end of the post): interface IPrimes { IEnumerable<int> GetPrimes(int retrieve); } Simple enough, right?  Anything that implements the interface will (hopefully) provide an IEnumerable of int, with the quantity specified in the parameter argument.  Next, I am going to implement this interface in the most basic way: public class DumbPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _analyzing = 4; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; //start dividing at 2 //divide until number is reached, or determined not prime for (int i = 2; i < _analyzing && isPrime; i++) { //if (i) goes into _analyzing without a remainder, //_analyzing is NOT prime if (_analyzing % i == 0) isPrime = false; } //if it is prime, add to found list if (isPrime) _foundPrimes.Add(_analyzing); //increment number to analyze next _analyzing++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } This is the simplest way to get primes in my opinion.  Checking each number by the straight definition of a prime – is it divisible by anything besides 1 and itself. I have included this code in a base class library for my solution, as I am going to use it to demonstrate a couple of features of ANTS.  This class library is consumed by a simple non-MVVM WPF application, and a simple MVC4 website.  I will not post the WPF code here inline, as it is simply an ObservableCollection<int>, a label, two textbox’s, and a button. Starting a new Profiling Session So, in Visual Studio, I have just completed my first stint developing the GUI and DumbPrimes IPrimes class, so now I want to check my codes efficiency by profiling it.  All I have to do is build the solution (surprised initiating a profiling session doesn’t do this, but I suppose I can understand it), and then click the ANTS menu, followed by Profile Performance.  I am then greeted by the profiler starting up and already monitoring my program live: You are provided with a realtime graph at the top, and a pane at the bottom giving you information on how to proceed.  I am going to start by asking my program to show me the first 15000 primes: After the program finally began responding again (I did all the work on the main UI thread – how bad!), I stopped the profiler, which did kill the process of my program too.  One important thing to note, is that the profiler by default wants to give you a lot of detail about the operation – line hit counts, time per line, percent time per line, etc…  The important thing to remember is that this itself takes a lot of time.  When running my program without the profiler attached, it can generate the 15000 primes in 5.18 seconds, compared to 74.5 seconds – almost a 1500 percent increase.  While this may seem like a lot, remember that there is a trade off.  It may be WAY more inefficient, however, I am able to drill down and make improvements to specific problem areas, and then decrease execution time all around. Analyzing the Profiling Session After clicking ‘Stop Profiling’, the process running my application stopped, and the entire execution time was automatically selected by ANTS, and the results shown below: Now there are a number of interesting things going on here, I am going to cover each in a section of its own: Real Time Performance Counter Bar (top of screen) At the top of the screen, is the real time performance bar.  As your application is running, this will constantly update with the currently selected performance counters status.  A couple of cool things to note are the fact that you can drag a selection around specific time periods to drill down the detail views in the lower 2 panels to information pertaining to only that period. After selecting a time period, you can bookmark a section and name it, so that it is easy to find later, or after reloaded at a later time.  You can also zoom in, out, or fit the graph to the space provided – useful for drilling down. It may be hard to see, but at the top of the processor time graph below the time ticks, but above the red usage graph, there is a green bar. This bar shows at what times a method that is selected in the ‘Call tree’ panel is called. Very cool to be able to click on a method and see at what times it made an impact. As I said before, ANTS provides 43 different performance counters you can hook into.  Click the arrow next to the Performance tab at the top will allow you to change between different counters if you have them selected: Method Call Tree, ADO.Net Database Calls, File IO – Detail Panel Red Gate really hit the mark here I think. When you select a section of the run with the graph, the call tree populates to fill a hierarchical tree of method calls, with information regarding each of the methods.   By default, methods are hidden where the source is not provided (framework type code), however, Red Gate has integrated Reflector into ANTS, so even if you don’t have source for something, you can select a method and get the source if you want.  Methods are also hidden where the impact is seen as insignificant – methods that are only executed for 1% of the time of the overall calling methods time; in other words, working on making them better is not where your efforts should be focused. – Smart! Source Panel – Detail Panel The source panel is where you can see line level information on your code, showing the code for the currently selected method from the Method Call Tree.  If the code is not available, Reflector takes care of it and shows the code anyways! As you can notice, there does seem to be a problem with how ANTS determines what line is the actual line that a call is completed on.  I have suspicions that this may be due to some of the inline code optimizations that the CLR applies upon compilation of the assembly.  In a method with comments, the problem is much more severe: As you can see here, apparently the most offending code in my base library was a comment – *gasp*!  Removing the comments does help quite a bit, however I hope that Red Gate works on their counter algorithm soon to improve the logic on positioning for statistics: I did a small test just to demonstrate the lines are correct without comments. For me, it isn’t a deal breaker, as I can usually determine the correct placements by looking at the application code in the region and determining what makes sense, but it is something that would probably build up some irritation with time. Feature – Suggest Method for Optimization A neat feature to really help those in need of a pointer, is the menu option under tools to automatically suggest methods to optimize/improve: Nice feature – clicking it filters the call tree and stars methods that it thinks are good candidates for optimization.  I do wish that they would have made it more visible for those of use who aren’t great on sight: Process Integration I do think that this could have a place in my process.  After experimenting with the profiler, I do think it would be a great benefit to do some development, testing, and then after all the bugs are worked out, use the profiler to check on things to make sure nothing seems like it is hogging more than its fair share.  For example, with this program, I would have developed it, ran it, tested it – it works, but slowly. After looking at the profiler, and seeing the massive amount of time spent in 1 method, I might go ahead and try to re-implement IPrimes (I actually would probably rewrite the offending code, but so that I can distribute both sets of code easily, I’m just going to make another implementation of IPrimes).  Using two pieces of knowledge about prime numbers can make this method MUCH more efficient – prime numbers fall into two buckets 6k+/-1 , and a number is prime if it is not divisible by any other primes before it: public class SmartPrimes : IPrimes { public IEnumerable<int> GetPrimes(int retrieve) { //store a list of primes already found var _foundPrimes = new List<int>() { 2, 3 }; //if i ask for 1 or two primes, return what asked for if (retrieve <= _foundPrimes.Count()) return _foundPrimes.Take(retrieve); //the next number to look at int _k = 1; //since I already determined I don't have enough //execute at least once, and until quantity is sufficed do { //assume prime until otherwise determined bool isPrime = true; int potentialPrime; //analyze 6k-1 //assign the value to potential potentialPrime = 6 * _k - 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); if (_foundPrimes.Count() == retrieve) break; //analyze 6k+1 //assign the value to potential potentialPrime = 6 * _k + 1; //if there are any primes that divise this, it is NOT a prime number //using PLINQ for quick boost isPrime = !_foundPrimes.AsParallel() .Any(prime => potentialPrime % prime == 0); //if it is prime, add to found list if (isPrime) _foundPrimes.Add(potentialPrime); //increment k to analyze next _k++; } while (_foundPrimes.Count() < retrieve); return _foundPrimes; } } Now there are definitely more things I can do to help make this more efficient, but for the scope of this example, I think this is fine (but still hideous)! Profiling this now yields a happy surprise 27 seconds to generate the 15000 primes with the profiler attached, and only 1.43 seconds without.  One important thing I wanted to call out though was the performance graph now: Notice anything odd?  The %Processor time is above 100%.  This is because there is now more than 1 core in the operation.  A better label for the chart in my mind would have been %Core time, but to each their own. Another odd thing I noticed was that the profiler seemed to be spot on this time in my DumbPrimes class with line details in source, even with comments..  Odd. Profiling Web Applications The last thing that I wanted to cover, that means a lot to me as a web developer, is the great amount of work that Red Gate put into the profiler when profiling web applications.  In my solution, I have a simple MVC4 application setup with 1 page, a single input form, that will output prime values as my WPF app did.  Launching the profiler from Visual Studio as before, nothing is really different in the profiler window, however I did receive a UAC prompt for a Red Gate helper app to integrate with the web server without notification. After requesting 500, 1000, 2000, and 5000 primes, and looking at the profiler session, things are slightly different from before: As you can see, there are 4 spikes of activity in the processor time graph, but there is also something new in the call tree: That’s right – ANTS will actually group method calls by get/post operations, so it is easier to find out what action/page is giving the largest problems…  Pretty cool in my mind! Overview Overall, I think that Red Gate ANTS CLR Profiler has a lot to offer, however I think it also has a long ways to go.  3 Biggest Pros: Ability to easily drill down from time graph, to method calls, to source code Wide variety of counters to choose from when profiling your application Excellent integration/grouping of methods being called from web applications by request – BRILLIANT! 3 Biggest Cons: Issue regarding line details in source view Nit pick – Processor time vs. Core time Nit pick – Lack of full integration with Visual Studio Ratings Ease of Use (7/10) – I marked down here because of the problems with the line level details and the extra work that that entails, and the lack of better integration with Visual Studio. Effectiveness (10/10) – I believe that the profiler does EXACTLY what it purports to do.  Especially with its large variety of performance counters, a definite plus! Features (9/10) – Besides the real time performance monitoring, and the drill downs that I’ve shown here, ANTS also has great integration with ADO.Net, with the ability to show database queries run by your application in the profiler.  This, with the line level details, the web request grouping, reflector integration, and various options to customize your profiling session I think create a great set of features! Customer Service (10/10) – My entire experience with Red Gate personnel has been nothing but good.  their people are friendly, helpful, and happy! UI / UX (8/10) – The interface is very easy to get around, and all of the options are easy to find.  With a little bit of poking around, you’ll be optimizing Hello World in no time flat! Overall (8/10) – Overall, I am happy with the Performance Profiler and its features, as well as with the service I received when working with the Red Gate personnel.  I WOULD recommend you trying the application and seeing if it would fit into your process, BUT, remember there are still some kinks in it to hopefully be worked out. My next post will definitely be shorter (hopefully), but thank you for reading up to here, or skipping ahead!  Please, if you do try the product, drop me a message and let me know what you think!  I would love to hear any opinions you may have on the product. Code Feel free to download the code I used above – download via DropBox

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