How to compare the performance of web frameworks - ruby-on-rails-3

I want to compare the performance of some web frameworks (Ruby on Rails and ASP MVC3) but I don't know how to get started... Should I measure how fast each framework renders e 10k long loop or how fast its renders 10k lines of html? Are there maybe programs that can help you with this? Also how can the server load be monitored? Any help is appreciated!
Thijs

With respect, this is an unanswerable question. Is a Porche faster than a Prius? Well, no, not when the Porche is in the shop :-).
The answer depends on what you're trying to accomplish, how you do it, and how you code it. For example, Rails goes out of its way to transparently cache as much as it can, and then makes it trivially easy to cache stuff on your command. Of course there's a way to do the same in ASP MVC3, but is it as easy?
Can you find, hire, and train a suitable team in that knows how to use the framework? What's the culture of the organization (Windows or Unix?). I could write a really fast application in MS-Access and the same application poorly in Rails against a high-performance database and the MS-Access app would win. It's far from a given that an application will be written well, optimized, or whatever.
These days, a well-written application is typically performance bound on data I/O, and if this is the case, then it's which database you use that might matter. The loop-test you propose would test almost nothing, unless you're writing an application that calculates pi to the billionth place, or something.
I am sure there are published benchmarks of application frameworks available, but again, they need to make assumptions about what the application actually has to do.
The reality is that any reasonable framework (which includes both of the two you mention) is likely to be as fast as necessary for most scenarios, and again, what you do, and how you architect and implement it are the far more likely culprits for performance problems.
Once you do choose, there's a great (awesome) tool called NewRelic RPM which works with several frameworks -- I use it with Rails, and it gives you internal metrics at a level of detail that is beyond belief.
I don't mean to be glib, or unhelpful. But this is a little bit of a sore spot for me -- in so many cases people say "we should use foo instead of bar because foo's faster", and weeks go by as bar is replaced by foo. And then there are little incompatibilities. And an unexpected bug. And then, well, for some reason the new one is a little slower. And then after it gets optimized, it's finally just as fast.
I'll step down from my soapbox now :-)

Related

Should I choose Hiberlite for integrating SQLite into my Win/iOS application?

I am a composer by profession and my computer science skills are limited though I program quite a bit of the software that I use.
What are the most reasonable ways to approach SQLite integration as a file format and database in an iOS app (it also needs to run on windows, but that is a secondary concern)?
I have been researching Hiberlite, which looks fantastic, but it seems to be little used and apparently it doesn't run well on embedded systems (iOS?) and chokes up when thousands of objects are in play. I haven't been able to get a sense of how severe those bottle necks are when running under those conditions.
The settings of thousands of objects (~50,000 though that number could expand) would be read every 1-10 seconds and written periodically. Read performance is more critical as write operations can stutter with out effecting the core operation of the app.
Given those conditions, how should I approach SQLite? My understanding is that without something like Hiberlite the entire database (many millions of entries) must be read and rewritten for every entry, is that less efficient. If that is the best approach is there a good resource to follow for implementing it?
Any advice would be greatly appreciated. My current software that I rely on is beyond buggy and needs refactoring, but due to my inexperience I am having a difficult time finding information about a reasonable approach.
I'm guessing you've probably found a solution for this by now, but I've been interested myself in embedding SQLite on Android and IOS, and I came across many C++-based ORM solutions.
Hiberlite looked possibly not fully mature (I didn't readily see a method of returning subsets of data, which is fairly standard). A framework which did draw my attention was the POCO:Data ORM library. It's based on the stream-based mechanism used in SOCI ORM. The POCO library is modular and optimised for embedded environments (I believe it also has a minimal external dependencies). Wikipedia has an article here, they outline some of its users, of which OpenFrameworks is one.
The WT ORM also looked pretty interesting.
I'm listing some of the other C++ ORM frameworks I found here, in no particular order:
http://soci.sourceforge.net
webtoolkit WT DBO ORM
http://debea.net
http://www.qxorm.com
http://sourceforge.net/apps/trac/litesql
http://otl.sourceforge.net
http://cppcms.com/sql/cppdb
http://dtemplatelib.sourceforge.net
http://code.google.com/p/qdjango

Code readability and UI design balance

I have worked a lot on improving how my code runs (and it's "beauty"), but when is the time to stop fixing, and start working on the UI?
Microsoft (in my opinion) seems to go with the nice-code, while Apple goes with nice UI (although Apple's developer examples do have very nice code).
I'm bad at balancing, when is it the time to work on one or the other?
Make it work, then make it elegant, then make it fast.
If the user doesn't like the program, the quality of the code is irrelevant. Once the user likes the program, then code quality becomes more important. And by "like" I mean a good user experience where the program doesn't crash, fulfills the need that the user has and adhere's to the Principle of Least Surprise.
Note I say "more important" because code is not something the user sees or is interested in. Code quality and "beauty" is important to developers because it's what they see of the program and what they hand over to other developers.
I remember reading something some time ago comparing (in general terms) software developed for the windows platform and software developed for OS X. In general terms it said that windows programs tended to be developed by developers who didn't spend too much time on the UI or thinking about the user experience. Their concentration was getting every piece of functionality they could think of into the program without any thought about it making sense. Mac OS X on the other hand tended to be developed by people concentrating on the user experience first and solving their problems. So it didn't necessarily have as much functionality, but what it did have was directly associated with what the user needed and was easy to use.
So when is it time to stop and think about the UI? The fact that you have asked the question makes me think it's time to stop right now. If anything I'd suggest that even before writing any code you should have drawn out a basic UI and worked out what sort of user experience your program is going to provide If you cannot work that out, you don't want to wasting time writing code because you will never use it.
Thats not to say I think code "beauty" is irrelevant. I spend time on making sure my code is well written, easy to follow and looks "good". But that's after I've figured out the UI and because I've had a lot of experience with cleaning up other people aweful code :-)
This is an incredibly broad question, and the answer is entirely a function of what you're building, why, and for whom.
Some random bits of conventional wisdom that I agree with:
If you're building broadly-applicable consumer software (e.g. for Mac or iOS), then the UI is a critical component of the application. Spend lots of time on it. :) Work with designers. If your software looks like crap, no one will want to use it. (Assuming nobody's going to make them: see next point.)
If you're building internal or enterprise tools, UI polish is probably less important.
Even if you're a one-man (or woman) operation, think of engineering as distinct from "product management". Product management is the thought process that determines what the software should do, and how it should work (and look). Engineering creates the reality, but has different tradeoffs. These are sometimes in conflict, which is hard to handle if you're one person, but try to wear different hats.
In all cases, your code should work, for some reasonable definition of work.
If it's ugly because it's hacked together, you're likely to run into accuracy/correctness problems sooner than if you construct it methodically. It will also be harder to maintain. The tradeoff here is almost never worth it. As you gain experience, you'll more naturally write clean code from the start, even if it's "scratch" code. You'll save time in the long run this way, and not be faced with later wholesale attempts to improve its beauty.
If you're on a team, or working with others, clean code is even more important. Find out if there are any "local" coding conventions, and work closely with colleagues.
As far as improving "how code runs", if you mean performance optimization, don't do any of that until you're sure you need to. Write the simpler code first, even if it's slower. It's likely that it won't be slow enough to matter.
Special case: if you're writing a game, long-term maintainability is less important, because they tend to be "throwaway" at some level. YMMV.

Porting VB6 app to VB.Net: Can anyone ballpark how much effort this is?

In 2002 I did a pretty large VB6 app for a client. It used a lot of UserControls and a 3rd party menu control (for putting icons next to menu names). It had dynamically "splittable" panels, TreeViews with multi-state checkboxes, etc. A very rich UI. My total time on the project was about 500 hours, which the client graciously let me spread over a whole month. (Yeah, it was that kind of job.) They were very happy, though, and they paid the bill on time with no argument.
So after having no contact with them for years, they suddenly call and wonder if I can update the app to .Net for them. My initial reaction is just to decline, since I don't use VB.Net. And having read a bunch of posts on SO about the difficulties of porting, etc., etc., I'm even more inclined to decline, so to speak.
Still, before I tell them no I am interested in roughly quantifying the effort it would take. I would love to hear from anyone who has done this kind of thing and has a feel for how much work it is. Was it:
Significantly less than the effort you used on the original?
Somewhat less than the effort you used on the original?
The same as the effort you used on the original?
More?
A lot more?
Please only respond if you have actually done this kind of port. And the answer doesn't have to be exact, since I really am only trying to ballpark this. My feeling is that the effort will be at least as much as it took for the original, if not more. But I could be wrong. Thanks for any help.
I have done what you've been asked. In my case it was an (amateur) bowling tournament mgmt system: Member database mgmt (personal info, IRS/Winnings info, mailing lists etc etc etc) , tournament mgmt (player assignments, scoring, lane ticket generation, check register for winnings and side-pots, etc etc etc) as well as IRS EDI generation for all winners in a given year. Plus about a billion little items scattered across ~ 50 screens/sub-screens.
The key is CLIENT UNDERSTANDING -- You must be clear that they understand that this is not trivial; this is a new adventure for BOTH of you (particularly if you are a new-comer to VB.Net) If they liked your work before then they may very well give you the leeway/freedom to learn VB.Net on their nickel.
Reading some of the previous answers let me make a few suggestions (based upon 30 years experience as a software developer, the last 20 of which as a consultant....)
TAKE THEIR MONEY IF THEY OFFER IT. You need to bring your skillset into the 20th century; let them pay for it (again, if they agree.) They may be Magazine surfing and want "the latest stuff" for NO GOOD REASON -- but maybe they realize that they can extend the life of (your) application by this port. In essence they may have all kinds of goofy reasons for doing it... if they are NOT hiring you to DECIDE whether or not this port is a good idea. Then you may express any dismay you have about the decision PROCESS out of good client relationship building; BUT if they want to do this then it might as well be your job.
Take all this mumbo-jumbo re: C# vs VB.Net with a grain of salt. I have worked EXCLUSIVELY in VB.Net / ASPX.net (vs C#) since its inception and have yet to come across ANY functionality NOT attainable in VB.Net. There are some 'purists' out there that just view VB.Net as a toy. Well, I came from the days of writing in Assembler, then C, then C++ (And you can throw in Fortran, PL1 for good measure) then VB5, then 6, then VB.Net ... and NOW JAVA for Android. Its ALL GOOD FUN... and each has it merits and drawbacks. Remember that C# and VB.Net are essentially just GUIs to achieve a meta-language intermediate. You can write a TERRIBLE (as measured by efficiency or memory use or whatever metric you choose!) Program in C# and a great one in VB.Net (and vice-versa.) DO NOT EQUATE GOOD PROGRAMMING WITH LANGUAGE SYNTAX. (... C# is "superior" ???? Gimme a break.)
I chose to allow the Visual Studio do most of the heavy lifting for the first pass. Then you go through the gazzillion errors and clean it up. It goes pretty fast.
BUT you need to decide whether or not to take advantage of any framework benefits that you had hand-coded in VB6. E.G. looping through a string to locate a specific character(s) is now as simple as The_String.IndexOf("c") I found that in my case I went through the code several times and took better and better advantage of the Class (i.e. object orientation) as well as framework goodies as I became comfortable... this adds to your development time (see CLIENT UNDERSTANDING mantra) BUT your code WILL BE MORE Efficient then it ever could have been in VB6. You could simply port to get the errors out and not take ANY advantage necessarily from the framework.
I have not found any issue with 3rd party active-x controls. You can add a reference to FRAMEWORK objects, COM objects, etc. It may even be likely that the control vendor has a .Net (managed code) version... OR there may be suitable alternatives since you wrote the thing in VB6. (See CLIENT UNDERSTANDING mantra)
So if your still reading, then now I will finally tell you that the second attempt at my application in VB.Net CONVERTED/PORTED from VB6 was ~ 1/3 of the original time to get to a working model... and I was learning the framework as well. (If your confident in your skill set, have learned a few languages through the years you will get the gist of VB.Net quickly --- its the SUBTLETIES that take awhile.)
I must caution you that the thing that can REALLY kill you if you do not preach the CLIENT UNDERSTANDING well enough is if they want to make changes WHILE you're porting (and this is VERY LIKELY since they've been using it for awhile... I was very true in my case as well.
There is no hard and fast rule here. It could be that changes will actually HELP YOU get to a better understanding the framework faster OR changes could be a real pain. Only you can determine which flavor they might be. AND if they look to be the PAINFUL type -- you might ask to do the conversion first so that you have reliably reproduced the functionality -- THEN go back and review the code to make changes and take advantage of the framework as necessary. But, as I said, there is NO Hard and Fast rules here -- and don't let the purists tell you differently --- remember they are probably the same guys that said that PASCAL was going to take over the world!
So after having no contact with them for years, they suddenly call and wonder if I can update the app to .Net for them.
You need to ask why they want this done.
It's a Bad Plan(tm) for clients to be making technical decisions on a whim. Before applying any solution, thoroughly understand their needs and their problem. Only after you understand the problem as they do should you make recommendations.
It could be that they're infatuated with a buzzword and want to be using the latest thing, or it could be any of a million other things. The solution to their problem could be something really easy, but if you don't find out what their problem is, you will never know the best way to solve that problem.
I would plan on it taking about 50% of the time and effort it took to create it in the first place.
I have done EXACTLY what you are asking about for a commercial software product that consisted of roughly 500 kloc. We balanced the desire for refactoring with the desire to get something working and released as quickly as possible.
It took nearly the entire team about 1 full year to get it done...for a product that took 4 years to create in the first place. It was a gigantic undertaking..not to be underestimated.
We are doing that exact thing right now, however it's slightly different. Instead of one huge application, there are many smaller ones. However, there are a few bigger ones in the list. What we found out is that it was significantly less work than we originally thought. BUT...the biggest unknowns had to do with third-party controls we had. If you have a lot of those to basically redesign, you will probably be looking at more work.
The one good suggestion I have is to use Visual Studio 2008 for the conversion (not VS 2005). There were far less problems when using the built-in converter in VS 2008 than there was with VS 2005. Not sure why, it just was that way.
So, I can't say that you won't spend 500 hours again, but most likely not. Most of your time should be spent on testing to verify no functionality was lost.
In my opinion,
Visual Basic 6 and Visual Basic .NET are so different that you should forget about their coincidence in their name, and treat this as a migration to .NET =P
I think that you have one big advantage and one disadvantage:
Advantage: you allready know what the application has to do. Probably you´ll have some meetings with your clients, in order to add some modifications or new features, but you have the major part of the requirements very clear. You´ll even have the old working application to see while you, or your team, are coding.
Disadvantage: you´ll have to learn a new language. Saying how much time is going to take, is very subjective. I´ve allways thought that learning a new language is not the problem, the big problem would be if you have to learn to program!. But you do know to program. You´ll know what you want to do, and you´ll have only to search how to do it in the new languaje.
Since you have to learn .NET, If you have to estimate, I think that you should suppose that it will take you at least the same as the previous application, even more.
My advice is too take the chance to learn this new language. And if you are more inclined to decline the project, let me give you another idea... Maybe you could estimate a little module of your application, and tell the client that you´ll try to do that module, to see how much it takes to you. The client should pay this little module, even if you decide not to continue.
You can´t tell the client that you know all the requirements, so they are saving money with you, in some way. And that they should take this little risk (we are talking about a little module), because who better than you to make the project, you know the old application perfectly!
If the client is right with this, you´ll can take the decision with more arguments. And If finally you decide to continue, with this little module done, you can estimate the whole project better than before.
Sorry, my English isn´t very good, and probably I´ve made many gramatical errors.
EDIT grammar mistakes... =P
This is a huge topic.
You should take a look at MS' Free Book - Upgrading Microsoft Visual Basic 6.0 to Microsoft Visual Basic .NET.
Were you to rewrite from scratch, rather than simply try and port the previous application, it shouldn't take too long. VB.Net has some features that will make the new application build take shorter. As it seems that you don't know VB.Net already, what will take you the most time is learn how to do things the new way(tm).
I'd go for two months this time.
But seriously, that's probably not far off — or even low — because the client will have some reason for needing the port done. It won't be just a straight port - they'll want some "small little enhancement" that will blow the whole project up.
Additionally, I'd worry a bit about the third party controls. Most of the rest of it should convert okay, but there's sometimes an issue finding a good analog to a 3rd party control in .Net.
I'm also concerned that you don't use vb.net. If you're a c# user and wanted to re-implement that way you'd be fine, but otherwise this is a non-starter. VB.Net is just different enough from vb6 for you to get yourself into trouble.
Aside from all that, I would expect it to be less work this time than last, because you have a very explicit design laid out in front of you that you merely need to follow.

Anybody using .netTiers?

I'm considering adopting .nettiers for a new project as it seems to provide a lot of functionality I could use.
Is anybody using it in anger (I'm getting the feeling it hasn't got the following it once had) and if so, what are your perceptions of it?
Also, I can't find any comparative performance metrics against things like SubSonic. Anybody have any strong feelings about its performance and scalability?
Many thanks
Tony
When I used NetTiers, I was very happy with it to an extent. You really need to learn the best ways to use it. There were definitely some weird bugs, things that had arbitrary limits and so forth. You have to be careful with it but it can definitely improve your productivity if you learn. I know CodeSmith has started putting more resoucres in it. The version 2.3 might be very solid. Although, the latest current stable version may be pretty solid, I haven't used it in awhile.
Honestly, at this point I prefer LLBLGen. I did try SubSonic a couple times. I didn't run into major bugs but I ended up switching, in both cases, to NetTiers. With SubSonic I felt that I was just typing out way too many string literals and it just didn't feel as mature as other alternatives.
Look at this. It provides you with a good X vs Y comparison between the two of them.
A Key point that i always revise when selecting a framework to work with is:
Will this Simplify, Make me more Productive, if you answer "Yes of course" to this, it doesnt matter what other benchmarks say, even if it's 10% slower in running than SubSonic or even faster, you should go with the framework you develop the fastest and most that you are the most comfy in.
I had some time this afternoon to run a head to head comparison between netTiers and SubSonic.
I used code generated using SubStage (part of the SubSonic 2.1 release) and I used RepositoryRecord as my base class.
I ran the same test against the same database using code generated by .netTiers 2.2
The test was a derivative of the one that Rob Conery used in his post:
http://blog.wekeroad.com/blog/subsonic-scaling/
When i say derivative, I mean I just wrote 100,000 records into the database.
I repeated each test on the same PC three times.
I found that .netTiers accomplished the task in 90 seconds.
Subsonic completed it in 104 seconds.
There was no more than a one second deviation from these averages.
Look at this. It provides you with a
good X vs Y comparison between the two
of them
Thanks - I've already read this post before, but it's over two years old and both projects have advanced a great deal since then.
Asking whether or not a framework will make me more productive or not is a very important consideration, but it's not the only one.
Another for me has to be "am I going to lose potential productivity gains because the framework I adopt is full of bugs, nasty to use, or just a PIA?" which is why I asked if people are using it in anger and what their experience is.
If .nettiers is 10% slower than subsonic, but gives me a whole bunch more features (such as better validation, business rule enforcement etc) then I can live with that. If its ten times slower, then I'd not consider it.
Many thanks
Tony

How to convince my co-workers not to use datasets for enterprise development (.NET 2.0+)

Everyone I work with is obsessed with the data-centric approach to enterprise development and hates the idea of using custom collections/objects. What is the best way to convince them otherwise?
Do it by example and tread lightly. Anything stronger will just alienate you from the rest of the team.
Remember to consider the possibility that they're onto something you've missed. Being part of a team means taking turns learning & teaching.
No single person has all the answers.
If you are working on legacy code (e.g., apps ported from .NET 1.x to 2.0 or 3.5) then it would be a bad idea to depart from datasets. Why change something that already works?
If you are, however, creating a new apps, there a few things that you can cite:
Appeal to experiencing pain in maintaining apps that stick with DataSets
Cite performance benefits for your new approach
Bait them with a good middle-ground. Move to .NET 3.5, and promote LINQ to SQL, for instance: while still sticking to data-driven architecture, is a huge, huge departure to string-indexed data sets, and enforces... voila! Custom collections -- in a manner that is hidden from them.
What is important is that whatever approach you use you remain consistent, and you are completely honest with the pros and cons of your approaches.
If all else fails (e.g., you have a development team that utterly refuses to budge from old practices and is skeptical of learning new things), this is a very, very clear sign that you've outgrown your team it's time to leave your company!
Remember to consider the possibility that they're onto something you've missed. Being part of a team means taking turns learning & teaching.
Seconded. The whole idea that "enterprise development" is somehow distinct from (and usually the implication is 'more important than') normal development really irks me.
If there really is a benefit for using some technology, then you'll need to come up with a considered list of all the pros and cons that would occur if you switched.
Present this list to your co workers along with explanations and examples for each one.
You have to be realistic when creating this list. You can't just say "Saves us lots of time!!! WIN!!" without addressing the fact that sometimes it is going to take MORE time, will require X months to come up to speed on the new tech, etc. You have to show concrete examples where it will save time, and exactly how.
Likewise you can't just skirt over the cons as if they don't matter, your co-workers will call you on it.
If you don't do these things, or come across as just pushing what you personally like, nobody is going to take you seriously, and you'll just get a reputation for being the guy who's full of enthusiasm and energy but has no idea about anything.
BTW. Look out for this particular con. It will trump everything, unless you have a lot of strong cases for all your other stuff:
Requires 12+ months work porting our existing code. You lose.
Of course, "it depends" on the situation. Sometimes DataSets or DataTables are more suited, like if it really is pretty light business logic, flat hierarchy of entities/records, or featuring some versioning capabilities.
Custom object collections shine when you want to implement a deep hierarchy/graph of objects that cannot be efficiently represented in flat 2D tables. What you can demonstrate is a large graph of objects and getting certain events to propagate down the correct branches without invoking inappropriate objects in other branches. That way it is not necessary to loop or Select through each and every DataTable just to get the child records.
For example, in a project I got involved in two and half years ago, there was a UI module that is supposed to display questions and answer controls in a single WinForms DataGrid (to be more specific, it was Infragistics' UltraGrid). Some more tricky requirements
The answer control for a question can be anything - text box, check box options, radio button options, drop-down lists, or even to pop up a custom dialog box that may pull more data from a web service.
Depending on what the user answered, it can trigger more sub-questions to appear directly under the parent question. If a different answer is given later, it should expose another set of sub-questions (if any) related to that answer.
The original implementation was written entirely in DataSets, DataTables, and arrays. The amount of looping through the hundreds of rows for multiple tables was purely mind-bending. It did not help the programmer came from a C++ background attempting to ref everything (hello, objects living in the heap use reference variables, like pointers!). Nobody, not even the originally programmer, could explain why the code is doing what it does. I came into the scene more than six months after this, and it was stil flooded with bugs. No wonder the 2nd-generation developer I took over from decided to quit.
Two months of tying to fix the chaotic mess, I took it upon myself to redesign the entire module into an object-oriented graph to solve this problem. yeap, complete with abstract classes (to render different answer control on a grid cell depending on question type), delegates and eventing. The end result was a 2D dataGrid binded to a deep hierarchy of questions, naturally sorted according to the parent-child arrangement. When a parent question's answer changed, it would raise an event to the children questions and they would automatically show/hide their rows in the grid according to the parent's answer. Only question objects down that path were affected. The UI responsiveness of this solution compared to the old method was by orders of magnitude.
Ironically, I wanted to post a question that was the exact opposite of this. Most of the programmers I've worked with have gone with the custom data objects/collections approach. It breaks my heart to watch someone with their SQL Server table definition open on one monitor, slowly typing up a matching row-wrapper class in Visual Studio in another monitor (complete with private properties and getters-setters for each column). It's especially painful if they're also prone to creating 60-column tables. I know there are ORM systems that can build these classes automagically, but I've seen the manual approach used much more frequently.
Engineering choices always involve trade-offs between the pros and cons of the available options. The DataSet-centric approach has its advantages (db-table-like in-memory representation of actual db data, classes written by people who know what they're doing, familiar to large pool of developers etc.), as do custom data objects (compile-type checking, users don't need to learn SQL etc.). If everyone else at your company is going the DataSet route, it's at least technically possible that DataSets are the best choice for what they're doing.
Datasets/tables aren't so bad are they?
Best advise I can give is to use it as much as you can in your own code, and hopefully through peer reviews and bugfixes, the other developers will see how code becomes more readable. (make sure to push the point when these occurrences happen).
Ultimately if the code works, then the rest is semantics is my view.
I guess you can trying selling the idea of O/R mapping and mapper tools. The benefit of treating rows as objects is pretty powerful.
I think you should focus on the performance. If you can create an application that shows the performance difference when using DataSets vs Custom Entities. Also, try to show them Domain Driven Design principles and how it fits with entity frameworks.
Don't make it a religion or faith discussion. Those are hard to win (and is not what you want anyway)
Don't frame it the way you just did in your question. The issue is not getting anyone to agree that this way or that way is the general way they should work. You should talk about how each one needs to think in order to make the right choice at any given time. give an example for when to use dataSet, and when not to.
I had developers using dataTables to store data they fetched from the database and then have business logic code using that dataTable... And I showed them how I reduced the time to load a page from taking 7 seconds of 100% CPU (on the web server) to not being able to see the CPU line move at all.. by changing the memory object from dataTable to Hash table.
So take an example or case that you thing is better implemented differently, and win that battle. Don't fight the a high level war...
If Interoperability is/will be a concern down the line, DataSet is definitely not the right direction to go in. You CAN expose DataSets/DataTables over a service but whether you SHOULD or is debatable. If you are talking .NET->.NET you're probably Ok, otherwise you are going to have a very unhappy client developer from the other side of the fence consuming your service
You can't convince them otherwise. Pick a smaller challenge or move to a different organization. If your manager respects you see if you can do a project in the domain-driven style as a sort of technology trial.
If you can profile, just Do it and profile. Datasets are heavier then a simple Collection<T>
DataReaders are faster then using Adapters...
Changing behavior in an objects is much easier than massaging a dataset
Anyway: Just Do It, ask for forgiveness not permission.
Most programmers don't like to stray out of their comfort zones (note that the intersection of the 'most programmers' set and the 'Stack Overflow' set is the probably the empty set). "If it worked before (or even just worked) then keep on doing it". The project I'm currently on required a lot of argument to get the older programmers to use XML/schemas/data sets instead of just CSV files (the previous version of the software used CSV's). It's not perfect, the schemas aren't robust enough at validating the data. But it's a step in the right direction. The code I develop uses OO abstractions on the data sets rather than passing data set objects around. Generally, it's best to teach by example, one small step at a time.
There is already some very good advice here but you'll still have a job to convince your colleagues if all you have to back you up is a few supportive comments on stackoverflow.
And, if they are as sceptical as they sound, you are going to need more ammo.
First, get a copy of Martin Fowler's "Patterns of Enterprise Architecture" which contains a detailed analysis of a variety of data access techniques.
Read it.
Then force them all to read it.
Job done.
data-centric means less code-complexity.
custom objects means potentially hundreds of additional objects to organize, maintain, and generally live with. It's also going to be a bit faster.
I think it's really a code-complexity vs performance question, which can be answered by the needs of your app.
Start small. Is there a utility app you can use to illustrate your point?
For instance, at a place where I worked, the main application had a complicated build process, involving changing config files, installing a service, etc.
So I wrote an app to automate the build process. It had a rudimentary WinForms UI. But since we were moving towards WPF, I changed it to a WPF UI, while keeping the WinForms UI as well, thanks to Model-View-Presenter. For those who weren't familiar with Model-View-Presenter, it was an easily-comprehensible example they could refer to.
Similarly, find something small where you can show them what a non-DataSet app would look like without having to make a major development investment.