meaning of 64bit: not only large memory, but large atomic integer

[Sean Kelly]

== Quote from redsea (redsea at 163.com)'s article
> When I implement some high performance program in linux 32bit, 32bit atomic if often not sufficient,
for example, If I want to hold a index & a timestamp to a atomic variable, 32bit is not enough,  in 64bit
environment, I can do that.

The IA-32 instruction set contains a 64-bit CAS operation in addition to
the 32-bit CAS.  You don't even need a 64-bit machine to do it!  The
atomics module in Tango supports 64-bit storeIf operations on 32-bit
Intel platforms.


Sean