Re: [zzdev] :gzz: Story of an unsuspected crash spiral (v.0706)

["Tuomas J. Lukka" <lukka@xxxxxx>]

> I thought that I managed to work for an hour till it crashed hard
>  (when I used the ESC key to go home). 
> 
> I started at maybe 4:30 pm, putting in the family data that I've been
>  using in my demo of the prototype.  Since I was just adding and
>  filling in cells (nothing risky, I figured), I was able to save that at 5 pm.

Did you alter the system list?

> >From that point I figured I'd better make frequent backups.
> 
> As I went on I did backups by copying the directory, not terminating
>  the program.  But at 6 pm it crashed hard (use of ESC key and
>  resulting strange condition).
> 
> I tried to restart with that same data, but it wouldn't.  

Big mistake. When you back up, first ALWAYS exit the program with 'q'.
There might be unflushed buffers, depending on the OS. You risk
total data corruption that way.

While the program is running, do not read OR write the data.

> Lesson learned: shut down completely at backup time.

> It just occurred to me-- could the successions of corrupted data
>  have had to do with not shutting down?  Do you do some
>  closure process on the data on shutdown that was not being
>  performed properly by just dragging out a copy of the data
>  directory?

Yes. Exactly so.

	Tuomas