Re: [siesta-dev] preferences

[prev] [thread] [next] [lurker] [Date index for 2002/10/11]

From: Nicholas Clark
Subject: Re: [siesta-dev] preferences
Date: 17:02 on 11 Oct 2002
On Fri, Oct 11, 2002 at 03:46:49PM +0100, Richard Clamp wrote:
> On Friday, Oct 11, 2002, at 13:24 Europe/London, Simon Wistow wrote:
> > On Thu, Oct 10, 2002 at 05:45:08PM +0100, Nicholas Clark said:
> >> However, is there any sort of sanity locking - presumably a race 
> >> condition
> >> can exist where (say) two e-mails both requesting configuration 
> >> changes
> >> can arrive, execute simultaneously:
> Last change wins.

I agree

>                    I think most of the by email changes be gated by ack 
> messages anyhow, so that I can't surreptitiously upset you by spoofing 
> an envelope and asking for extra header munging.

But I meant that if the stuff calling the Storage system knows that it is
"doing stuff" where it reads data, modifies it and then re-writes data, then
it needs to implement a form transactions to be robust.

(And certainly whatever implements the Storage system needs to be told to
do locking, else there's the non-zero probability of corrupting DBM files
or the like on disk. Rare, yes. Impossible no. Therefore it will happen to
someone at some point)

That's all I meant to say.

(And I don't give a fuck for long term "well, they shouldn't do two things at
once" arguments. Short term, yes, valid. Long term, it will allow lusers to
shag systems. And admins will get pissed off and use something else.)

Nicholas Clark

There's stuff above here

Generated at 13:56 on 01 Jul 2004 by mariachi 0.52