Dirk,
I have found that on a moderately loaded server session
varibles are not reliable. In one application I had to copy all the
information from session variables into request variables and put try/catch
blocks around the cfset request.x = session.x assignment statements and put that
code in a loop that iterates until successful to ensure the session
variables would copy properly to the request scope. I still see 10-20 of
these errors a day from our cluster of four production
servers.
At this point I do not even attempt to use session
variables in Cold Fusion. Usually, I use client variables (as those are
usable across our cluster) and seem pretty reliable but of course those can't
hold your cfc. Perhaps you could code a solution where you store the data
behind the cfc as XML in a client variable and recreate the cfc with each
request from the XML data in the client variable. It may also be possible
to store the cfc in an application variable - likely as a structure with a
specific key you place in a client cookie. These are not ideal solutions
but if your application has relatively low usage either may work for
you.
Hope this helps,
Tom Woestman
From: Dirk Meilinger [mailto:[EMAIL PROTECTED]
Sent: Friday, October 29, 2004 11:05 AM
To: [EMAIL PROTECTED]
Subject: Session Variable SNAFU
Hi All,
I am having a severe problem with session variables in an order management application I am working on. The application stores a rather large order object (cfc) in the SESSION scope and modifies it as changes are made via methods of the CFC. For some reason at random times the order cfc just plain dissappears from the session scope, never in the same place in the code. One post on a page will work fine, and then refreshing the same page will sometimes cause the object to just go away.
Is it possible this is related to memory usage by the objects size? Are there any guidelines as to a limit of the aggregate size of objects in SESSION scope? I was under the impression it was only limmited by the physical memory of the app server. Observation as to memory allocation shows plenty of room as far as free memory. The problem occurs both on *nix and Windows app servers.
Does anyone know of any way to track what is happening in the SESSION scope? Is it possible some way to log when/if SESSION scope variables are deleted by the server? I suspect it might be possible that the session is timing out, but it should not be as our application tags and server defaultgs are all set for 2 hours and this happens several times in a span of 5-10 minutes.
Thanks for any advice!
I am having a severe problem with session variables in an order management application I am working on. The application stores a rather large order object (cfc) in the SESSION scope and modifies it as changes are made via methods of the CFC. For some reason at random times the order cfc just plain dissappears from the session scope, never in the same place in the code. One post on a page will work fine, and then refreshing the same page will sometimes cause the object to just go away.
Is it possible this is related to memory usage by the objects size? Are there any guidelines as to a limit of the aggregate size of objects in SESSION scope? I was under the impression it was only limmited by the physical memory of the app server. Observation as to memory allocation shows plenty of room as far as free memory. The problem occurs both on *nix and Windows app servers.
Does anyone know of any way to track what is happening in the SESSION scope? Is it possible some way to log when/if SESSION scope variables are deleted by the server? I suspect it might be possible that the session is timing out, but it should not be as our application tags and server defaultgs are all set for 2 hours and this happens several times in a span of 5-10 minutes.
Thanks for any advice!
