[tor-bugs] #4443 [Tor Relay]: Implement counter mode faster on x86 and x86_64

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#4443: Implement counter mode faster on x86 and x86_64
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 Reporter:  nickm        |          Owner:                    
     Type:  enhancement  |         Status:  new               
 Priority:  normal       |      Milestone:  Tor: 0.2.3.x-final
Component:  Tor Relay    |        Version:                    
 Keywords:               |         Parent:                    
   Points:               |   Actualpoints:                    
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Comment(by tmpname0901):

 > unaligned integer access is just as fast as aligned integer access (this
 seems to be the case on x86 and x86_64

 This is definitely not true.  There is a performance penalty across the
 x86(_64) line for memory accesses which are not aligned to data type.

 From a performance perspective, unaligned memory access are Bad; accesses
 straddling cache lines are Really Bad; accesses straddling pages are
 Horrifically Bad.  I think you get the idea :-)

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Ticket URL: <https://trac.torproject.org/projects/tor/ticket/4443#comment:1>
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