I'm working on a real-time application (lets call it App1) which is communicating with another application (App2). I used VS2008 and both applications are in C++. Recently I converted the App1 project to VS2010 and right after that it started crashing (I use VS2010 Premium Ver. 10.0.30319.1). Crash dump shows that right before a crash, App2 tries to send a request to App1 for multiple times without receiving any response. So I thought maybe converting App1 to VS2010 screwed the performance and it takes a long time for App1 to generate the response. Does using VS2010 has any effect on the performance (compared to VS2008)?
+6
A:
Well of course it has "some" effect on the performance. The compiler is newer, and in many regard better.
The problem you are suffering is unlikely to be as a result of the compiler going wrong however. Its possible you have made an assumption that no longer holds true under the C++0x features introduced in 2010 but I'd suggest its far more likely that you have a bug in the VS2008 version as well. You need to figure out why its hanging and see what you can do to stop that hang happening. It is quite probable that the timings have been changed around using 2010 and an assumption you've made (and you should never assume things will work in a specific way ... either know or look it up) has come back to bite you in the arse.
Probably not the kinda answer you were looking for though ... but I'd definitely bet on it being a bonafide bug!
Goz
2010-09-30 20:53:29
good points, thanks, I guess I'll downgrade to VS2008 and compile and see if it crashes again or not. If it doesn't, then it is probably related to some "assumption".
Ahmad
2010-09-30 21:35:11
Personally I run 2008 and 2010 alongside each other (ie both are installed on my dev system). As I get the opportunity, all my code is being upgraded to 2010 and I've not had any problems so far (which is why I think its likely to be an actual bug).
Goz
2010-10-01 07:30:44
+1
A:
The thing to do is not guess around about this and that.
The thing to do is find the bug and fix it.
It's tricky with asynchronous apps that coordinate with message passing. The way I handle jobs like that is to generate a detailed time-stamped log of the message traffic from/to each app. I take those logs and merge them together into a single timeline. Then I study the timeline and look for things that don't work as expected.
This is work. It can take many hours, and you will probably have to repeat it, but you will find the problem. I assume you're the kind of programmer who will tackle a tough job and see it through.
Mike Dunlavey
2010-09-30 22:33:03
Exactly; Actually I believe one has to consider all possibilities and try them out (that's what I mean by guessing). I already have this log and I can see where the delay is and in what type of message. I analyzed all new functions and couldn't find any relation between that messaging and new functions; so my next guess is that it is caused by some sort of change in the timings of 2010. So I'm testing and if it is the problem, the I'll fix it.
Ahmad
2010-10-01 13:51:50
@Ahmad: Sounds like you know what to do. In my experience "by guess and by golly" is like the slow road to China. If there's a diagnostic technique that tells me the problem, even if it seems slow and tedious, it's faster and more certain than guessing. Good luck.
Mike Dunlavey
2010-10-01 14:20:35