Journaling vs. Softupdates

[Alex Zbyslaw]

Zev Thompson wrote:

> Apparently one of the Google Summer of Code projects is to add 
> journaling  to UFS. When it already has softupdates, why? I've seen 
> benchmarks that  seem to indicate that softupdates performs as well or 
> better in most  cases, though I have nothing on hand to substantiate 
> that. I thought the  only real disadvantages of softupdates were:
>
> - harder to code and implement (though this is already done, so should 
> not  be an issue)
> - sometimes deleting files does not free space right away
>
> Possibility of data loss, I'm guessing, is the same with either.  
> Filesystem corruption is similarly very unlikely.
>
> So why the change? Thanks in advance for any answers.

Large filesystems without journaling take too long to fsck.

There's plenty of messages about this out there, otherwise I wouldn't 
have know the answer :-)

--Alex