On Mon, 1 Nov 2004, Vishal Soni wrote: > 2. Is there anything i shud consider or change along with tuning above > Macro values? Don't try changing the page size. Not only will you need to change all the page table handling and a few device drivers, but you may also lose compatibility with userspace programs that depend on 4kB page granularity for mprotect(). > 3. As we know that the user space process can't access kernel address space and when shmat system call is > used the shared memory is mapped to the Process's Virtual Address space, > Now the question is from where in the memory does shared memory come from... i mean does it come from > User Space or Kernel Space.........or from process's Data Segment.... ?????? Shared memory areas are virtual memory. Kernel address space is virtual memory. It is common for the same page of physical memory to be mapped both by userspace processes and by the kernel. Rik -- "Debugging is twice as hard as writing the code in the first place. Therefore, if you write the code as cleverly as possible, you are, by definition, not smart enough to debug it." - Brian W. Kernighan -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
