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GeneralRe: How to copy CPU Electronic Serial Number during Installation of a program Pin
Nelek13-Jun-08 3:09
protectorNelek13-Jun-08 3:09 
GeneralRe: How to copy CPU Electronic Serial Number during Installation of a program Pin
Larry Mills Sr14-Jun-08 2:08
Larry Mills Sr14-Jun-08 2:08 
GeneralRe: How to copy CPU Electronic Serial Number during Installation of a program Pin
Nelek15-Jun-08 22:28
protectorNelek15-Jun-08 22:28 
QuestionIs C# a JOKE? [modified] Pin
bigchump12-Jun-08 11:06
bigchump12-Jun-08 11:06 
AnswerRe: Is C# a JOKE? Pin
Baltoro12-Jun-08 13:01
Baltoro12-Jun-08 13:01 
GeneralRe: Is C# a JOKE? Pin
bigchump12-Jun-08 13:12
bigchump12-Jun-08 13:12 
GeneralSearched at MSDN Pin
Baltoro12-Jun-08 13:38
Baltoro12-Jun-08 13:38 
GeneralRe: Is C# a JOKE? Pin
Simon P Stevens12-Jun-08 22:28
Simon P Stevens12-Jun-08 22:28 
bigchump, I've posted some suggestions in the c# forum regarding your problem, so I don't want to talk about that here.

What I'm interested in is why you seem to think 64 bit applications should automatically run faster?

Firstly, being 64 bit does not mean faster. a 64 bit app means all your number variables (ints/longs) are twice the size (ints become 64 bits large, longs become 128 bits), so they take up more space. More importantly, all pointers to objects become 64 bits long, so also take up more space. This could mean a potential slow down, as there are lots of hidden issues here related to processing 64 bit pointers.

As I understand it, your app is processing a bunch of data. There is a good chance that on a 64 bit system, this is taking up extra space so can't all fit in memory at one time. This means that the data will be swapped out of memory to the disk. This is a huge time cost. You can investigate this by using a tool such as ProcessExplorer from SysInternals[^]. Try looking at the amount of memory your app is using, and more importantly, the number of page faults that occur during the main processing phase of the app. Compare this to your old c++ version.

The primary reason to switch to 64 bit is that it allows you to address a much larger amount of memory. 32 bit systems are limited to 4GB. 64 bit on the other hand can access 17.2 billion gigabytes. This is of most use on high end database servers. 64 bit does not on it's own give a speed improvement. If anything, switching to 64 bit (using native c++) and not doing anything else is likely to hurt performance.

Finally, real pure 64 bit apps will not run on 32 bit operating systems (not even if you have an 64 bit CPU, the actual operating system must be 64 bit. This means you need windows XP x64 or Vista 64). C# code set to compile to "any cpu" is actually a special case that can change and run as 32 or 64 bit depending on the operating system it is being run on. This is a common misunderstanding. Can you confirm exactly what operating system and compiler settings you are using for your 64 bit app?

Simon

AnswerRe: Is C# a JOKE? Pin
Alan Balkany13-Jun-08 4:57
Alan Balkany13-Jun-08 4:57 
GeneralRe: Is C# a JOKE? Pin
bigchump13-Jun-08 6:11
bigchump13-Jun-08 6:11 
GeneralRe: Is C# a JOKE? Pin
Alan Balkany13-Jun-08 6:25
Alan Balkany13-Jun-08 6:25 
GeneralRe: Is C# a JOKE? Pin
bigchump13-Jun-08 9:19
bigchump13-Jun-08 9:19 
GeneralRe: Is C# a JOKE? Pin
Alan Balkany13-Jun-08 11:22
Alan Balkany13-Jun-08 11:22 
QuestionReadDirectoryChangesW Problem~~~ Pin
york52812-Jun-08 8:13
york52812-Jun-08 8:13 
AnswerRe: ReadDirectoryChangesW Problem~~~ Pin
Nibu babu thomas12-Jun-08 17:26
Nibu babu thomas12-Jun-08 17:26 
GeneralRe: ReadDirectoryChangesW Problem~~~ Pin
york52812-Jun-08 18:30
york52812-Jun-08 18:30 
GeneralRe: ReadDirectoryChangesW Problem~~~ Pin
york52812-Jun-08 19:18
york52812-Jun-08 19:18 
GeneralRe: ReadDirectoryChangesW Problem~~~ Pin
Nibu babu thomas12-Jun-08 19:39
Nibu babu thomas12-Jun-08 19:39 
GeneralRe: ReadDirectoryChangesW Problem~~~ Pin
york52812-Jun-08 20:18
york52812-Jun-08 20:18 
GeneralRe: ReadDirectoryChangesW Problem~~~ Pin
Nibu babu thomas12-Jun-08 20:23
Nibu babu thomas12-Jun-08 20:23 
GeneralRe: ReadDirectoryChangesW Problem~~~ Pin
york52812-Jun-08 20:31
york52812-Jun-08 20:31 
QuestionMDI Application with more than one child? Pin
CrocodileBuck12-Jun-08 5:31
CrocodileBuck12-Jun-08 5:31 
AnswerRe: MDI Application with more than one child? Pin
Nelek12-Jun-08 5:46
protectorNelek12-Jun-08 5:46 
GeneralRe: MDI Application with more than one child? Pin
CrocodileBuck12-Jun-08 6:55
CrocodileBuck12-Jun-08 6:55 
GeneralRe: MDI Application with more than one child? Pin
JudyL_MD12-Jun-08 7:52
JudyL_MD12-Jun-08 7:52 

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