[sugar] Notes on joyride-258 and 630

[Albert Cahalan]

Michael Stone writes:

> Second, Record appears to be unable to play back sound. It complains
> of errors trying to write files due to lack of space. I will speculate
> about the cause: we are now equipping activities with a 1 MB tmpfs. If
> Record is attempting to put any large data into
> $SUGAR_ACTIVITY_ROOT/tmp, it's writes will likely fail. People for
> whom having a 1MB tmpfs is a problem should explain what they're
> trying to do on the mailing list and we'll work out something
> reasonable.

This limit does not make sense.

An activity can allocate well over 100 MB via malloc.
The tmpfs filesystem comes from the same storage pool.

By default, Linux would allow 128 MB on the XO. This too
is wrong; having a limit only serves to make things fail.

Note that tmpfs usage should show up in the ring, which
of course needs to get fixed.

The alternative to tmpfs wears out the nand flash.