[Arm-netbook] laptop main board, power board and ingenic jz4775 cpu card

[Paul Sokolovsky]

Hello,

On Tue, 24 Nov 2015 15:53:10 +0000
Luke Kenneth Casson Leighton <lkcl at lkcl.net> wrote:

[]

> RAM is (or will soon be) the inhibiting factor around the adoption of
> single-board computers.


> > I haven't paid enough
> > attention to 32-bit ARM recently to say whether similar limits
> > apply there,
> 
>  absolutely they are - because the peripherals are all
> memory-addressed, and the boot ROM also has to be addressed somehow.

Just as x86-32, ARMv7 has physical address extension
http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0438i/CHDCGIBF.html ,
so it can address more than 4Gb of physical memory. That still leaves
4Gb of virtual memory per process, and thanks god - bloating memory size
doesn't mean growing its speed, so the more memory, the slower it all
works.

Generally, it's pretty depressing to read this memory FUD on mailing
list of "sustainable computing" project. What mere people would need
more memory for? Watching movies? Almost nobody puts more than 1Gb
because *it's not really needed*. And for sh%tty software, no matter if
you have 1, 2, or 8GB - it will devour it and sh%t it all around,
making the system overall work slower and slower with more memory. (I'm
currently sitting on 16Gb box with constant 100% cpu load - it's Firefox
collecting garbage in its 6Gb javascript heap - forever and ever).

For comparison, my latest discovery is relation database engines which
can execute queries in few *kilobytes* of RAM -
https://github.com/graemedouglas/LittleD and Contiki Antelope
http://dunkels.com/adam/tsiftes11database.pdf



-- 
Best regards,
 Paul                          mailto:pmiscml at gmail.com