Re: Which file-system is good for power down?

[Dieter <netbsd%sopwith.solgatos.com@localhost>]

> > But Linux's ext will CORRUPT YOUR DATA!!!  (I'll give you one guess  
> > how
> > I know this.)  Who cares how fast it boots if your data is corrupted?
> 
> How will ext3 corrupt my data after hard crash ?.

I have observed data corruption due to crappy penguin filesystem.
I have not spent the time to figure out exactly how it happens.
I assume the source code is available.

> AFAIK soft-dependiences keep filesystem in consistent state with  
> ordering metadata writes. softdeps keep ordered metadata(which were  
> not written to fs yet.) in memory. And therefore if you have hard  
> crash with heavy-io server you can loose more than with journaling fs.  
> Keep number of softdeps in-memory buffers small is not solution  
> because it slows your io then.

Unix has had read-ahead & write-behind for decades.  Any write-behind
will result in lost data if the system goes down hard.  With softdeps
at least you don't lose the data that did make it out to disk.