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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 :-)
In a sense NHibernate seems convenient because it leads to less typing, and then propably less errors.
I think NHibernate can be used in every size of application because it is really easy to use (especially with FluentNHibernate) and you it does much work for you like generating SQL
queries, mapping values to objects and so on. Even in typical small applications you need to put a great part of the whole effort on the data persistence layer, so why don't let NHibernate do the work for you?
Best Regards,
Oliver Hanappi
It is tough to judge what you are looking for based on the terseness of your question, as there is really a lot of nuance in an answer to this.
In many ways, as the others here say, it depends on your project and your knowledge of nHibernate. But it also depends on a lot of other factors as well...
If you think your small project might grow into a large project someday that could make a better argument for it as you then have a strong foundation on which to grow.
If your goal is learning nHibernate (or another ORM) then a small project may be the best place to get your feet wet and try it out. (Also try Linq2SQL, and other ORMs as well and go with what you find works the best for you.)
I personally use nHibernate for all of my projects large and small (where possible due to other constraints). But I've also been working with it for a while and a good base of code that I can reuse. So that factors into the time part of an answer. nHibernate has a pretty steep learning curve so if you need something done quick nHibernate may not be optimal.
I hope that helps, if you can refine your question and your goals a little more in your question it will assist the rest of us in getting you some better feedback and ideas to help you.
It depends what you mean by small, and how accomplished you are with Hibernate. I'd find that the extra overhead of getting set up would not make using it a good option on a little project personally. I'd say the same about other frameworks like Spring too, they are far more useful on larger projects with lots of developers.
It's not if you have a strong knowledge of NH, if you have some model generator, if you use some DBMS other than SQL Server.
I think that if you have a DB on SQL server, you're quin in a hurry, you are knowledgeable on LINQ, LINQ2SQL might be a good choice. Fast and RAD.
I agree with Oliver but would add the caveat that it is only easy to use once you know how (and that may take awhile). If you haven't gotten on top of the learning curve and need a simple app, NHib will slow you down; otherwise use it on anything that isn't completely trivial or a throw away! So your simple but effective app has one more sound piece of infrastructure as it scales and adapts to requirement changes.
HTH,
Berryl
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.
I am really torn right now between using O/R mappers or just sticking to traditional data access. For some reason, every time I bring up O/R mappers, fellow developers cringe and speak about performance issues or how they're just bad in general. What am I missing here? I'm looking at LINQ to SQL and Microsoft Entity Framework. Is there any basis to any of these claims? What kind of things do I have to compromise if I want to use an O/R mapper. Thanks.
This will seem like an unrelated answer at first, but: one of my side interests is WWII-era fighter planes. All of the combatant nations (US, Great Britain, Germany, USSR, Japan etc.) built a bunch of different fighters during the war. Some of them used radial engines (P47, Corsair, FW-190, Zero); some used inline liquid-cooled engines (Bf-109, Mustang, Yak-7, Spitfire); and some used two engines instead of one (P38, Do-335). Some used machine guns, some used cannons, and some used both. Some were even made out of plywood, if you can imagine.
In the end, they all went really really fast, and in the hands of a competent, experienced pilot, they would shoot your rookie ass down in a heartbeat. I don't imagine many pilots flew around thinking "oh, that idiot is flying something with a radial engine - I don't have to worry about him at all". Everyone understood that there were many different ways of achieving the ultimate goal, and each approach had its particular advantages and disadvantages, depending on the circumstances.
The debate between ORM and traditional data access is just like this, and it behooves any programmer to become competent with both approaches, and choose the option that is right for the job at hand.
I struggled with this decision for a long time. I think I was hesitant for two primary reasons. First, O/R mappers represented a lack of control over what was happening in a critical part of the app and, second, because so many times I've been disappointed by solutions that are awesome for the 90% case but miserable for the last 10%. Everything works for select * from authors, of course, but when you crank up the complexity and have a high-volume, critical system and your career is on the line, you feel you need to have complete control to tune every query pattern and byte over the wire. Most developers, including me, get frustrated the first time the tool fails us, and we cannot do what we need to do, or our need deviates from the established pattern supported by the tool. I'll probably get flamed for mentioning specific flaws in tools, so I'll leave it at that.
Fortunately, Anderson Imes finally convinced me to try CodeSmith with the netTiers template. (No, I don't work for them.) After more than a year using this, I can't believe we didn't do it sooner. My team uses Visual Studio DB Pro, and on every check-in our continuous integration build drops out a new set of data access layer assemblies. This handles all the common, low risk stuff automatically, yet we can still write custom sprocs for the tricky bits and have them included as methods on the generated classes, and we can customize the templates for the generated code as well. I highly recommend this approach. There may be other tools that allow this level of control as well, and there is a newer CodeSmith template called PLINQO that uses LINQ to SQL under the hood. We haven't that yet examined (haven't needed to), but this overall approach has a lot of merit.
Jerry
O/RM tools designed to perform very well in most situations. It will cache entities for you, it will execute queries in bulks, it has a very low level optimised access to objects which is way faster than manually assigning values to properties, they give you a very easy way to incorporate variations of aspect oriented programming using modern technics like interceptors, it will manage entity state for you and help resolve conflicts and many more.
Now cons of this approach usually lies in lack of understanding of how things work on a very low level. Most classic problem is "SELECT N+1" (link).
I've been working with NHibernate for 2.5 years now, and I'm still discovering something new about it almost on a daily basis...
Good. In most cases.
The productivity benefit of using an ORM, will in most case outweigh the loss of control over how the data is accessed.
There are not that many who would avoid C#, in order to program is MSIL or Assembly, although that would give them more control.
The problem that i see with a lot of OR mappers is that you get bloated domain objects, which are usually highly coupled with the rest of your data access framework. Our developers cringe at that as well :) It's just harder to port these object to another data access technology. If you use L2S, you can take a look at the generated code. It looks like a complete mess. NHibernate is probably one of the best at this. Your entities are completely unaware of your data access layer, if you design them right.
It really depends on the situation.
I went from a company that used a tweaked out ORM to a company that did not use a ORM and wrote SQL queries all the time. When I asked about using an ORM to simplify the code, I got that blank look in the face followed by all the negatives of it:
Its High Bloat
you don't have fine control over your queries and execute unnecessary ones
there is a heavy object to table mapping
its not dry code because you have to repeat your self
on an on
Well, after working there for a few weeks, I had noticed that:
we had several queries that were almost identical, and alot of times if there was a bug, only a handful would get fixed
instead of caching common tables queries, we would end up reading a table multiple times.
We were repeating our selves all over the place
We had several levels of skill level, so some queries were not written the most efficiently.
After I pointed most of this out, they wrote a "DBO" because the didn't want to call it an ORM. They decided to write one from scratch instead of tweaking out one.
Also, alot of the arguments come from ignorance against ORM's I feel. Every ORM that I have seen allows for custom queries, and even following the ORM's conventions, you can write very complex and detailed queries and normally are more human readable. Also, they tend to be very DRY, You give them your schema, and they figure the rest out, down to relationship mapping.
Modern ORM's have a lot of tools to help you out, like migration scripts, multiple DB types accessed to the same objects so you can leverage advantages of both NOSQL and SQL DB's. But you have to pick the right ORM for your project if your going to use one.
I first got into ORM mapping and Data Access Layers from reading Rockford Lhotka's book, C# business objects. He's spent years working on a framework for DAL's. While his framework out of the box is quite bloated and in some cases, overkill, he has some excellent ideas. I highly recommend the book for anyone looking at ORM mappers. I was influenced by his book enough to take away a lot of his ideas and build them into my own framework and code generation.
There is no simple answer to this since each ORM provider will have it's own particular pluses and minuses. Some ORM solutions are more flexible than others. The onus is on the developer to understand these before using one.
However, take LinqToSql - if you are sure you are not going to need to switch away from SQL Server then this solves a lot of the common problems seen in ORM mappers. It allows you to easily add stored procedures (as static methods), so you aren't just limited to generated SQL. It uses deferred execution, so that you can chain queries together efficiently. It uses partial classes to allow you to easily add custom logic to generated classes without needing to worry about what happens when you re-generate them. There is also nothing stopping you using LINQ to create your own, abstracted DAL - it just speeds up the process. The main, thing, though is that it alleviates the tedium and time required to create basic CRUD layer.
But there are downsides, too. There will be a tight coupling between your tables and classes, there will be a slight performance drop, you may occasionally generate queries that are not as efficient as you expected. And you are tied in to SQL Server (though some other ORM technlogies are database agnostic).
As I said, the main thing is to be aware of the pros and cons before pinning your colours to a particular methodology.
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.