$_SESSION data

How much is too much?

[aspr1n]

Wondered if anyone had any thoughts or experience on how "big" datawise session data can realistically get, and any thoughts on performance penalties etc etc.

Also (and/or) if there is any way to store immutable data across sessions - preferably not by reading and writing to files, as a way of bypassing the above question. Would be very interested to here of other PHP COM users in this regard.

Cheers,

asp

[aspr1n]

To be more specific, I am looking both at application specific variables as well as user specific data - but more than I would want to store in $_SESSION.

One thing did occur to me - has anyone tried writing to the $_SERVER global, and using that as their applications data space?

asp

(appologies for replying to my own post - I don't seem to get owner edit.)

[kmarcus]

one of the applications which i am currently working on stores upwards of 50k per session. There are typically a thousand or so 'active' sessions, although the average size is about 5k.

i haven't see any issue related to performance, yet.