Hi... On Wed, Apr 7, 2010 at 06:27, Youngwhan Song <breadncup@xxxxxxxxx> wrote: > What if actual physical memory is only 256MB? How does kernel divide virtual > memory? Still the same as before, 3:1 vm split, 896 MB in ZONE_NORMAL and so on. However, in this case there is no ZONE_HIGHMEM since all memory cells are directly addressable >Do we need to specify the region to kernel? Or will kernel itself > decide it automatically? Practically (this is something that I just rather guess, but I am pretty confident), the kernel will be mapped to somewhere around the first 10-100 MiB, leaving the reserved BIOS memory hole. Thus, the rest are available for dynamic allocation, be it for user space or kernel space. Virtually, thanks to the page table mapping, it will look like single continous address space where user space takes the first 3 GiB and kernel uses the upper 1 GiB. -- regards, Mulyadi Santosa Freelance Linux trainer and consultant blog: the-hydra.blogspot.com training: mulyaditraining.blogspot.com -- To unsubscribe from this list: send an email with "unsubscribe kernelnewbies" to ecartis@xxxxxxxxxxxx Please read the FAQ at http://kernelnewbies.org/FAQ
