No surprise on memory

[John Gilmore]

> What about using a NAND partition as swap?  Has this ever been done?
> Given that partition support is a recent development it seems unlikely.

Swapping to the soldered-in NAND chips is a very bad idea.  It will
tend to wear them out rapidly.  Even if you use load-leveling software
(e.g. swapping to a file in a jfffs2 filesystem), the problem is that
if you do start wearing out serious numbers of flash blocks, the
laptop becomes toast; it requires a soldering iron and spare chips to
fix it.

A much more reliable scheme would be to swap to an SD card, if one is
plugged in and contains a swap partition (or a file in its root called
SWAPFILE).  See http://dev.laptop.org/ticket/8410.  Even a small,
cheap SD card could double or triple the available virtual RAM space.
And if an SD card gets worn out, you merely pull it out of the laptop,
throw it away, and buy a new one (for a fraction of the original cost,
since Moore's Law has been working in your favor in the intervening
years).  

This doesn't solve the least-common-denominator problem of people without
SD cards -- but it does offer a user, or a deployment, a very simple and
relatively cheap way to solve most problems related to physical RAM size.

On the topic of memory overload in general:

Older XO releases did much better things when they ran out of physical
memory:  they tended to rapidly kill off some process, leaving the system
largely functional.  In 767, the system instead goes from usable to
molasses-like in a period of seconds, then freezes totally for minutes
or hours.  As far as I know, nobody has debugged why that changed.  The
prior behavior was infinitely preferable.

	John