On 9/3/05, Thayumanavar Sachithanantham <thayumker@xxxxxxxxx> wrote: > Am i correct that If we have 1 G of physical RAM on our system, 128 MB will > be reserved for temporary mappings? But this won't be used for any purpose > since we don't need any temporary mapping(which is required for >1 GB). Then > is it that 128 MB physical memory doesn't serve any purpose? Please clarify. > > Thayumanavar S. > The 3G/1G split is for Virtual Addresses not physical addresses. So 128MB here mentioned is for Virtual Memory not for Physical memory, and 0 to 896MB of physical is actually directly mapped to 1G of virtual space ((1024M - 128M) = 896MB) ........ So 128MB of Virtual Space (not physical) is always reserved by kernel for its page tables and mapping related stuff. And almost all the physical memory is free to be used by the processes/tasks of user/kernel..... -- Fawad Lateef -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
