> You will see that if you repeat the above steps > multiple times ( after the program exits), > the stack in 'pmap' output & > 'vsize' in ps output keeps changing , though > the Resident set size of the process remains > same across all invocations. > > Could somebody please explain this behaviour . this is done deliberately for 2 reasons 1) Performance: By changing the stack to different positions, you get less cache aliases, so you can use the cpu cache better 2) Security: By having a different and unpredictable stack place in memory, stack based buffer overflow exploits are harder to create. (and in combination with other security measures, really really hard ;) -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
