On Tue, Jun 06, 2000 at 09:23:20PM +0200, Giuseppe Boi wrote: > Matteo Merlin wrote: > > > Ciao gente, scusate la mia inesperienza e le > > domande assillanti ma Linux mi trova soltanto 64 Mb di RAM nonostante > > io ne abbia installati 128... Come faccio a farglieli trovare tutti ? > > Grazie! > > Al prompt di lilo digita: > linux mem=128 > > Almeno credo........!! Quasi ci sei ma non del tutto :-) Così dici al kernel (se ben ricordo) di partire con 128 bytes, non molti in realtà :-))) Vediamo un po' cosa dice il BootPrompt-HOWTO: 3.3.1. The `mem=' Argument This argument has two purposes: The original purpose was to specify the amount of installed memory (or a value less than that if you wanted to limit the amount of memory available to linux). The second (and hardly used) purpose is to specify mem=nopentium which tells the Linux kernel to not use the 4MB page table performance feature. The original BIOS call defined in the PC specification that returns the amount of installed memory was only designed to be able to report up to 64MB. (Yes, another lack of foresight, just like the 1024 cylinder disks... sigh.) Linux uses this BIOS call at boot to determine how much memory is installed. If you have more than 64MB of RAM installed, you can use this boot argument to tell Linux how much memory you have. Here is a quote from Linus on the usage of the mem= parameter. ``The kernel will accept any `mem=xx' parameter you give it, and if it turns out that you lied to it, it will crash horribly sooner or later. The parameter indicates the highest addressable RAM address, so `mem=0x1000000' means you have 16MB of memory, for example. For a 96MB machine this would be `mem=0x6000000'. If you tell Linux that it has more memory than it actually does have, bad things will happen: maybe not at once, but surely eventually.'' Note that the argument does not have to be in hex, and the suffixes `k' and `M' (case insensitive) can be used to specify kilobytes and Megabytes, respectively. (A `k' will cause a 10 bit shift on your value, and a `M' will cause a 20 bit shift.) A typical example for a 128MB machine would be "mem=128m". Ok, quindi si può usare mem=128m, direi. Però è una discreta rottura digitarlo tutte le volte. Vediamo se si può fare di meglio; vediamo ancora lo stesso HOWTO: LILO comes with excellent documentation, and for the purposes of boot args discussed here, the LILO append= command is of significant importance when one wants to add a boot time argument as a permanent addition to the LILO config file. You simply add something like append = "foo=bar" to the /etc/lilo.conf file. It can either be added at the top of the config file, making it apply to all sections, or to a single system section by adding it inside an image= section. Please see the LILO documentation for a more complete description. Quindi mettiamo un append = "mem=128m" nel lilo.conf, lanciamo lilo, poi un bel reboot e vediamo cosa succede... -- Fabio Coatti http://www.ferrara.linux.it/members/cova Ferrara Linux Users Group http://ferrara.linux.it GnuPG fp:9765 A5B6 6843 17BC A646 BE8C FA56 373A 5374 C703 Old SysOps never die... they simply forget their password.
