N-tier Remoting Frustrations
February 21st, 2005
People DO want n-layer, because that provides reuse, maintainability and overall lower costs. Logical separation of UI, business logic, data access and data storage is almost always of tremendous benefit.
People MIGHT want n-tier if they need the scalability or security it can offer, and if those benefits outweigh the high cost of building a physically distributed system. But the cost/benefit isn’t there as often as people think, so a lot of people build physical n-tier systems for no good reason. They waste time and money for no real gain. This is sad, and is something we should all fight against.
I think I agree with this in total.
The project I work on has hit basically every problem with Remoting that exists.
Unbelievably slow dataset serialization (see KB829740). Kind of a big issue for us because many of our developers aren’t so comfortable with creating their own data structures / objects, and consequently were relying very heavily on ADO objects. I resolved the speed issue by implementing my own formatter sink.
SocketExceptions (specifically, WSAENOBUFS) when transporting huge amounts of data. To some extent this is mitigated by better hardware. Although Q322975 refers to this as a “BUG,” we spoke with the Remoting development team through our premier support guys and they refer to this as designed behavior. There isn’t a quick fix (ie, registry change) here, so I’m going to have to try putting in a compression sink to get us some headroom.
The lack of a default remote call timeout. This killed us in production because of 1) a network problem and 2) some bad codes that circumvented the HttpRuntime’s executionTimeout in a very unfortunate way. It took us 4 horrendous days of the servers crashing every 20 minutes with three Microsoft CPR people on-site to finally figure out what the problem was.
There are probably a few others which I am forgetting now. I am still talking to MSFT reps about the second, but I have no expectations that that will get anywhere.
But getting back to my main point (yes, I had one). The really frustrating part about this for me is that I don’t even consider our middle tier to be necessary. We put it there primarily for security purposes, and I don’t know, maybe we get that. But with respect to the way most of our developers write code, this is no help. It doesn’t necessarily create a logical service boundary, because nobody really gave them the direction to do that. To an extent it just makes the spaghetti worse.
Now for my secondary point. A lot of this is certainly our fault. But what drives me crazy is comments like this one:
This does assume you listened to advice from people like Ingo Rammer, Richard Turner and myself and avoided creating custom sinks, custom formatters or custom channels. If you ignored all this good advice then you’ll get what you deserve I guess…
It’s frustrating as hell to be backed into creating workarounds for lousy performance which you (well, your boss, who mandated this architecture) were never warned about and then to be openly mocked for doing so by the ‘experts.’ If we had known that Remoting would be throwing us this many problems, we probably would not have tried to use it for n-tier, and maybe with a little luck we would have decided against our flavor of n-tier altogether.
Get us some better advice, folks.