Jolly good Dain, but like you thought, it doesn't meet my criteria. I'm not
trying to be a stickler here, but I really don't think it's possible for
PURELY read actions on application variables to cause problems. (still have
to check with Ray Camden per Cameron's suggestion).
The reason for my apparently contrived problem is that I have an
administrative interface that is only accessed during website "builds" where
I close down the whole site in IIS, point the name to a different page that
says "I'm sorry" and then manually go into the IP to verify a successful
build. During some of this checking, I re-initialize the application
variables, for good measure. This is the only time the application variables
ever get written. There is no code anywhere else to do it, and I am always
the only one on the admin area. Again, when I set these application
variables, I know FOR SURE that no users are on the site - no one is hitting
the app variables in read action.
I have indeed tried the scenario of one frame looping through writing the
variable while the other read the variable. If every read and write action
is locked in all the frames, there are no errors. But if the read frames are
not locked and the write frame is locked, then there are errors. Also, as
you could guess, if nothing is locked, I get a bunch of errors.
So the bet still stands (deathclock.com notwithstanding)
NAT
> -----Original Message-----
> From: Dain Anderson [mailto:[EMAIL PROTECTED]]
> Sent: Wednesday, April 25, 2001 12:21 PM
> To: Fusebox
> Subject: Re: the $5 bet - crash a server with unlocked application scope
> READs
>
>
> Nat,
>
> With the following code, I was successful in crashing the server, but I'm
> not sure if it meets the requirements you're wanting. It uses 3 files:
> application.cfm, test1.cfm, and test2.cfm. All I did was create a
> new folder
> with the 3 files in it, opened two separate browser windows with test1 in
> one window and test2 in another. I loaded both, hit refresh twice, and
> received the "Request canceled or ignored by serverServer busy
> ..." error in
> the first window and the "An error occurred while evaluating the
> expression:
> Application.CrashMe" in the other window. When the count was
> 1000-10000, it
> worked fine; 50,000 and two successive refreshes killed the whole server.
>
> Application.cfm:
> ===============
> <cfapplication name="test">
>
>
> Test1.cfm:
> ===========
>
> <cfif not isdefined("Application.CrashMe")>
> <cflock scope="APPLICATION" timeout="5" type="EXCLUSIVE">
> <cfset Application.CrashMe = "Kaboom!">
> </cflock>
> </cfif>
>
> <cfloop from="1" to="50000" index="i">
> <cfset Ouch = Application.CrashMe>
> </cfloop>
>
> Test2.cfm:
> ===========
>
> <cfloop from="1" to="50000" index="i">
> <cfset Ouch = Application.CrashMe>
> </cfloop>
>
> I have screen shots if you want to see them.
>
> Dain Anderson
> Caretaker, CF Comet
> http://www.cfcomet.com/
>
>
>
>
> ----- Original Message -----
> From: "Nat Papovich" <[EMAIL PROTECTED]>
> To: "Fusebox" <[EMAIL PROTECTED]>
> Sent: Wednesday, April 25, 2001 1:32 PM
> Subject: the $5 bet - crash a server with unlocked application scope READs
>
>
> > The subject pretty much says it all, but I'd like to see someone crash a
> > server or produce a pcode exception error or (getting easy here) produce
> one
> > of those "donteverusethisvariablenameinyourcfmlcode123456789" errors by
> > using concurrent unlocked application scoped variable reads.
> >
> > I've already built a frameset with 50 frames, each frame page
> looping over
> > the output of an application variable 100,000 times. Now out of those 5
> > million read hits to my application variable that occur within the space
> of
> > maybe 10 seconds, NONE produce any error whatsoever, no matter how many
> > times I try. Of course, doing 5 million WRITE hits will produce errors
> > pretty quickly, and eventually destroy my server. Anybody have Silk or
> Load
> > Runner?
> >
> > I'm not interested in session variable locking issues, nor with
> cfquery's
> > cachedwithin attribute. I only want to see application variable reads
> > causing detrimental effects to a CF server.
> >
> > $5 to be delivered at the next major CF conference, should I be able to
> > reproduce the error on my machine (single proc p3-650, 256 mb ram, CF 5
> Beta
> > 3, PWS, NT 4 Workstation SP6). The cash only goes to the first person...
> >
> > Good luck - I don't think it's possible!
> >
> > NAT
> > Nat Papovich
> > Webthugs Consulting
> > ICQ 32676414
> > "If it was hard to write,"
> > says the Real Programmer,
> > "it should be hard to understand."
> >
> >
> >
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