Re: Take your system down with Cartesian Joins

2008/8/12 <Tommy.Holden@xxxxxxxxxxxxxxxxxxxxx>:

not applicable in this situation! if the system is going down...it's
going down. trying to build a report to show you that will only speed up
the crash!...but if you have to peddle your wares...when disk space climbs
that fast then there's no way your product (or any other i know of) can
help in the situation presented.

I think some of it depends on how quickly the storage gets devoured.
We've had repeated issues with a client/server packages where user
queries generates joins over very large tables and when the results
don't come back in five minutes the user closes the window. The
iSeries carries on building the data until it gets spotted. Often this
can grow at a rate where we wouldn't notice a big jump in disk use,
but it creeps up steadily (I've seen 30GB+ in temp storage). I put a
background monitor together that looks at overall disk used and
individual jobs temporary storage -
http://www.dbg400.net/cgi-bin/twiki/view/DBG400/DasdMon - and that has
cured the problem[1] for us.

Regards, Martin
[1] Of alerting us to the issue and holding the affected job - it
doesn't solve the issue that the 3rd party application allows in the
first place :(