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				October 20th, 2011, 06:33 PM
			
			
			
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 Corporal |  | 
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				 Re: 64x version of Dominions? 
 
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					Originally Posted by Loren  64bit doesn't add one bit of speed unless you're doing 64bit arithmetic.  In general it will actually cost you a bit of speed as 64 bit code is bigger than 32 bit code. |  Yes!  That's so true, if you are reading your 64-bit words over an 8-bit bus. |  
	
		
	
	
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				October 21st, 2011, 04:54 PM
			
			
			
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 First Lieutenant |  | 
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				 Re: 64x version of Dominions? 
 
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					Originally Posted by Deathblob  
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					Originally Posted by Loren  64bit doesn't add one bit of speed unless you're doing 64bit arithmetic.  In general it will actually cost you a bit of speed as 64 bit code is bigger than 32 bit code. |  Yes!  That's so true, if you are reading your 64-bit words over an 8-bit bus. |  The memory bus is at least 64 bits, that's not a problem.
 
The problem is 64 bit code is simply bigger than 32 bit code--fewer lines of code fit into the on-chip caches, you end up with more read cycles to memory. |  
	
		
	
	
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				October 21st, 2011, 10:36 PM
			
			
			
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 Corporal |  | 
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				 Re: 64x version of Dominions? 
 
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					Originally Posted by Loren  
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					Originally Posted by Deathblob  
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					Originally Posted by Loren  64bit doesn't add one bit of speed unless you're doing 64bit arithmetic.  In general it will actually cost you a bit of speed as 64 bit code is bigger than 32 bit code. |  Yes!  That's so true, if you are reading your 64-bit words over an 8-bit bus. |  The memory bus is at least 64 bits, that's not a problem.
 
The problem is 64 bit code is simply bigger than 32 bit code--fewer lines of code fit into the on-chip caches, you end up with more read cycles to memory. |  Well, I thought those reads should be twice as fast, so I didn't believe you, and went googling.
http://www.osnews.com/story/5768/Are...naries_/page1/ 
It's a bit old, and Sparc of all things.  But looks like you are right.    
64bit had ~+20% bigger binaries, ~-10% slower execution. |  
	
		
	
	
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				October 22nd, 2011, 11:58 AM
			
			
			
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 First Lieutenant |  | 
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				 Re: 64x version of Dominions? 
 
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					Originally Posted by Deathblob  
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					Originally Posted by Loren  
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					Originally Posted by Deathblob  Yes!  That's so true, if you are reading your 64-bit words over an 8-bit bus.
 |  The memory bus is at least 64 bits, that's not a problem.
 
The problem is 64 bit code is simply bigger than 32 bit code--fewer lines of code fit into the on-chip caches, you end up with more read cycles to memory. |  Well, I thought those reads should be twice as fast, so I didn't believe you, and went googling.
http://www.osnews.com/story/5768/Are...naries_/page1/ 
It's a bit old, and Sparc of all things.  But looks like you are right.    
64bit had ~+20% bigger binaries, ~-10% slower execution. |  The 64bit processor reads everything faster, whether the executable is 32bit or 64bit. |  
	
		
	
	
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				October 24th, 2011, 04:52 PM
			
			
			
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 Second Lieutenant |  | 
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				 Re: 64x version of Dominions? 
 
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					Originally Posted by Loren  The problem is 64 bit code is simply bigger than 32 bit code--fewer lines of code fit into the on-chip caches, you end up with more read cycles to memory. |  How long does it take for the size of "on-chip cache" to double on average PC? |  
	
		
	
	
	
	
	
	
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