[Zope] is zope a solution?
Jim Penny
jpenny@universal-fasteners.com
Fri, 31 Aug 2001 16:00:49 -0400
On Fri, Aug 31, 2001 at 08:39:29PM +0100, tonyl wrote:
> On Friday 31 Aug 2001 20:18 pm, Jim Penny wrote:
>
> >
> > Yes, I am saying that the version I have crashes once or twice a week.
> > No, it does not make it at all unusable. There are 86400 minutes in
> > a week. this makes it available 99.9976% of the time. It is automatically
> > restarted after a minute without response goes by, so I do not have to
> > be here, etc.
> >
>
> What planet are you using zope on Jim.? Your days last a real long time (or
> my maths is awful) ;-)
Ah damn, that is seconds per week. (Too used to thinking in seconds.)
Make that 99.86% availablity.
>
> > Apache in my experience is better in terms of uptime. But I have had it
> > crash, too. I have had PostgreSQL crash. I have has AS/400 services
> > crash. Once you get beyond 3 9's of uptime, it starts to cost money.
> > I am running on clone hardware with no ECC, etc. Prepare not to have
> > 99.999% uptime, and you can handle 99.99% uptime quite well.
>
> For me, the issue is which of those minutes it's out of action. In my
> situation, the application will be hammered at the start of the month, week
> and morning (in that order). Most of the available minutes for statistical
> purposes won't have much in the way of system activity. So 1 minute in peak
> time is quite a high %age for the project. The equipment will probably be an
> 8 way sun box with oracle.
Look, you are running on way more hardware with way better and way
more expensive gear than I am used to. It sounds like you have
an actual budget. If you can't get better uptime, I would be surprised.
I come from a different situation entirely. In my situation, if it can't
be done with hand-me-down hardware and a bit of sweat equity, then it
can't be done.
Also, all of that activity sounds like read activity. Read activity,
in my experience, hardly ever triggers problems. at least 90% of my
problems have been write related.
(And I still would be a bit surprised if your user base is upset
by an occaisional minute of downtime. The web has trained people
way too well that downtime is normal!)
>
> I guess it has a user definable check-zope-is-up period? I'll soon change it
> if it hasn't! (if I can).
It can be shortened, but beware (a bit). You do not want the period so short
that zope cannot completely be reawakened. That is, you do not want to
start hammering a restart process so hard that it starts taking down
processes before they can start responding.
Jim Penny
>
> Thanks,
> Tony
>