on GUIs and such things

[Jonathan S. Shapiro]

> On Thu, Jul 20, 2000 at 08:45:10PM -0400, Kragen Sitaker wrote:
> > Persistence is useful for folks that need quick reboots; indeed,
> > Windows 2000 and Linux both have the ability now to persist a running
> > system image to disk so as to reboot more quickly; unfortunately, PCs
>
> How do you do that on Linux?

It's not really accurate to say that Win2K or Linux do this. It's a function
of the BIOS software, often called "suspend" or "sleep mode".

> Well I think it's better to just leave the data in RAM all the time,
> rather than copy it back to something that's artifically designed to
> resemble "disk" space (FLASH).  This has been the approach of two
> of the more successful ones (Newton and Palm)....

Unfortunately, alpha hits really do damage memory. You want a storage
mechanism that provides greater error checking (this can be had with ECC)
and some hope of recovery (this cannot be had with RAM unless you have some
other reference image).


> Memory leaks and
> corruption are absolutely verboten when you aren't planning on
> starting your memory image over from scratch once in a while.  It would
> be best to exclusively use languages which prevent these problems

You are correct. Unfortunately, such languages aren't yet good enough to be
used for operating systems, and operating system requirements (low level bit
manipulations whose format is dictated by some register specification)
conflict with safe pointer and safe language requirements.

EROS and KeyKOS take a middle ground: unbelievably paranoid code writing
coupled with regular consistency checks that are designed to catch all the
errors we can think of before the state is saved. Also some redundant
representation.

shap