So you mean that it is mapped to a 512MB ram instead of more than 1GB? I thought there is some trick there to map kernel uniquely to 1GB space. -----Original Message----- From: Lukas Ruf [mailto:ruf@xxxxxxxxx] Sent: Thursday, July 15, 2004 12:19 PM To: Lei Yang Cc: PLEASE REPLY TO THE LIST; Kernel Newbies Subject: Re: Physical memory Please do NOT top-post! See <http://www.rawip.org/style.html>. > Lei Yang <leiyang@xxxxxxxxxxxx> [2004-07-15 18:08]: > > > > Lei Yang <leiyang@xxxxxxxxxxxx> [2004-07-15 17:46]: > > > > > > Have a very basic question here, but it is kind of annoying me. The > > > kernel virtual area ( 3-4GB in virtual address) maps to the first > > > 1GB of physical RAM. But it is so common that we only have a machine > > > of 256MB/512MB etc. What is going on? > > > > > > > I assume: > > - your machine has only 512MB of real memory. > > - the mapping, i.e. the address translation, is carried out by the > > memory management unit in accordance to the configuration > > page table directories. > > > Do you mean that physical memory is NOT real memory? > well, what do you mean then? I assume you box has 512MB installed, right? So it IS real memory. wbr, Lukas -- Lukas Ruf | Wanna know anything about raw | <http://www.lpr.ch> | IP? -> <http://www.rawip.org> | eMail Style Guide: <http://www.rawip.org/style.html>| -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
