massive disk space leak vs thresh_update

[David Relson]

On Mon, 13 Dec 2004 05:54:10 -0500
Tom Allison wrote:

> Matthias Andree wrote:

...[snip]...

> I wonder how much perfomance cost we'll pay for all this transactional 
> benefit.  I personally have never had a problem with any of these 
> database issues with a possible exception of locking reads when writing 
> to the database.  But procmail retries.

Greg reported some major timing penalties with an earlier 0.93.x
release.  Matthias fixed the problem and bogofilter with transactions is
essentially the same speed as without transactions.

> I read the rest of your post and realize that my experience is based on 
> a mail server that would be considered modest at best.  Therefore my 
> opinions should be considered with that in mind.
> 
> The only concern that I might have that's legitimate would be the payoff 
> between performance and integrity.  I've always run a bogoutil dump 
> daily with running with many updates and still have weekly today (no 
> updates).  I don't know how often we actually see a problem with 
> database corruptions taking place.  But I do know that bogofilters 
> performance has been very good in the past.

Why are you doing daily backups?  The usual reason is to avoid problems
with corrupted databases.  I've been running daily backups for a year
(or more), because I _have_ experienced corruption, though not in a long
time.  The integrity of transactions has the promise of making backups
unnecessary, except to protect against hardware failures.