>On 01/22/2013 10:50 PM, Gary Mills wrote:
>> On Tue, Jan 22, 2013 at 11:54:53PM +0000, Edward Ned Harvey 
>> (opensolarisisdeadlongliveopensolari
s) wrote:
>> Paging out unused portions of an executing process from real memory to
>> the swap device is certainly beneficial. Swapping out complete
>> processes is a desperation move, but paging out most of an idle
>> process is a good thing. 
>It gets even better.  Executables become part of the swap space via
>mmap, so that if you have a lot of copies of the same process running in
>memory, the executable bits don't waste any more space (well, unless you
>use the sticky bit, although that might be deprecated, or if you copy
>the binary elsewhere.)  There's lots of awesome fun optimizations in
>UNIX. :)

The "sticky bit" has never been used in  that form of SunOS for as long
as I remember (SunOS 3.x) and probably before that.  It no longer makes 
sense in demand-paged executables.


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