[isabelle-dev] Reasons mira crashes

[Makarius]

On Wed, 28 Nov 2012, Gerwin Klein wrote:

> This may be entirely unrelated, but I've just had to re-clone the afp hg 
> repository in my home directory at TUM because it made mercurial crash 
> on pull, and failed integrity checking.
>
> The only other time I've ever had to do that in the past few years of 
> using mercurial was because of file corruption due to a broken hard disk 
> (two cases). If this happens frequently to us, something may be very 
> wrong with storage on the macbroy/lxbroy machines.

The reliability of NFS at TUM has indeed degraded a bit, maybe already 
more than 5 years ago, but it is hard to pin down.


>From the many possibilities to host Mercurial repositories for multi-user 
access, we have the worst possible solution.  We knew this already in 2008 
for the initial setup, and now there is this comprehensive overview: 
http://mercurial.selenic.com/wiki/PublishingRepositories?action=show&redirect=ServerInstall

We have the "shared disk" configuration, with "Advantages: can use 
existing setup", "Disadvantages: generally restricted to intranets, not 
generally recommended due to general issues with network filesystem 
reliability".


So we still carry a lot of CVS baggage stemming from 1993, not just in the 
low-level technological sense.

Nothing new, all known already.  I usually ignore it to avoid the trouble 
of thinking about more fundamental changes.


 	Makarius