on 12/30/2009 01:08 PM Dirk Heinrichs wrote the following:
> Am Mittwoch 30 Dezember 2009 11:49:39 schrieb Thanasis:
>> I have a netbook (Acer Aspire One A110L) and installed a 1GB DDR2 in the
>> available slot, for a total of 1.5GB or RAM.
>> The BIOS reports it as 1.5GB and so does grml linux (booting from usb),
>> but the installed gentoo linux reports only 904600 kB:
>
> With more than 1G of memory, you should set CONFIG_HIGHMEM4G=y.
> HTH...
> Dirk
I thought CONFIG_HIGHMEM4G had to do with more than 4GB of RAM.
Now I can see that the associated help says it is for an amount between
1 and 4GB.
That should be it. The option name confused me.
I will try it and report back.
Thanks :-)
Thanasis <[email protected]> writes:
> I thought CONFIG_HIGHMEM4G had to do with more than 4GB of RAM.
> Now I can see that the associated help says it is for an amount between
> 1 and 4GB.
Depends on the "split" used. With 2 GB : 2 GB you can have all-lowmem
1.5 GB RAM, without CONFIG_HIGHMEM*. 2 GB of per-process address space
is usually not a problem.
x86-64 removes such limits.
--
Krzysztof Halasa
on 12/31/2009 04:59 PM Krzysztof Halasa wrote the following:
> Thanasis <[email protected]> writes:
>
>> I thought CONFIG_HIGHMEM4G had to do with more than 4GB of RAM.
>> Now I can see that the associated help says it is for an amount between
>> 1 and 4GB.
>
> Depends on the "split" used. With 2 GB : 2 GB you can have all-lowmem
> 1.5 GB RAM, without CONFIG_HIGHMEM*. 2 GB of per-process address space
> is usually not a problem.
How do you implement that? What do you mean 2GB:2GB split ?
Thanasis <[email protected]> writes:
>> Depends on the "split" used. With 2 GB : 2 GB you can have all-lowmem
>> 1.5 GB RAM, without CONFIG_HIGHMEM*. 2 GB of per-process address space
>> is usually not a problem.
> How do you implement that? What do you mean 2GB:2GB split ?
See "make menuconfig", Processor type and features -> Memory split. You
need to select "EMBEDDED" and "EXPERIMENTAL" first. What you need for
1.5 GB RAM is VMSPLIT_2G.
The idea is that the CPU address space is divided: ca. 2 GB (in this
configuration) for user space (for each process - instead of 3 GB),
2 GB - 128 MB (or something like that, I don't remember exactly) for
physical RAM, and the last 128 MB or so for PCI devices and other
things.
--
Krzysztof Halasa
on 01/01/2010 03:38 PM Krzysztof Halasa wrote the following:
> Thanasis <[email protected]> writes:
>
>
>>> Depends on the "split" used. With 2 GB : 2 GB you can have all-lowmem
>>> 1.5 GB RAM, without CONFIG_HIGHMEM*. 2 GB of per-process address space
>>> is usually not a problem.
>>>
>> How do you implement that? What do you mean 2GB:2GB split ?
>>
> See "make menuconfig", Processor type and features -> Memory split. You
> need to select "EMBEDDED" and "EXPERIMENTAL" first. What you need for
> 1.5 GB RAM is VMSPLIT_2G.
>
> The idea is that the CPU address space is divided: ca. 2 GB (in this
> configuration) for user space (for each process - instead of 3 GB),
> 2 GB - 128 MB (or something like that, I don't remember exactly) for
> physical RAM, and the last 128 MB or so for PCI devices and other
> things.
>
Hmm..., but are EMBEDDED options suitable for a netbook like the A110L ?
Thanasis <[email protected]> writes:
> Hmm..., but are EMBEDDED options suitable for a netbook like the A110L ?
This "EMBEDDED" just means "don't touch these unless you really know
what you're doing".
BTW I remember using VMSPLIT 2 GB : 2 GB on server-class machines,
before they were upgraded to x86-64.
--
Krzysztof Halasa
on 01/04/2010 01:10 AM Krzysztof Halasa wrote the following:
> Thanasis <[email protected]> writes:
>
>
>> Hmm..., but are EMBEDDED options suitable for a netbook like the A110L ?
>>
> This "EMBEDDED" just means "don't touch these unless you really know
> what you're doing".
>
> BTW I remember using VMSPLIT 2 GB : 2 GB on server-class machines,
> before they were upgraded to x86-64.
>
Do you mean that I should try it? Is there any gain over using
CONFIG_HIGHMEM4G ?
Thanasis <[email protected]> writes:
> Do you mean that I should try it? Is there any gain over using
> CONFIG_HIGHMEM4G ?
You may want to try, HIGHMEM4G is (may be) slower, depending on load.
Google should find something about that.
--
Krzysztof Halasa