Occasional empty session file?

Walt

Occaionally the contents of a session file on the server seem to be removed.

98% of the time all works ok though.

As far as I can see it does not seem to be related to timeframe. - but may be related to how busy things get?

Cookie and session do not seem to be timing out.

Any pointers as to what might cause this would be appreciated.

--
using Redhat 9, php 4.2, postgresql 7.3, apache

Thanks

Walt

dalecosp

How busy is the server?

What are your settings for session "gc" (that is, garbage collection) in php.ini??

I dunno, but it's a possibility to investigate....

Walt

Thanks for the pointer

I have

session.gc_probability=1
session.gc_maxlifetime = 1440

..away to do some reading on this....

would the garbage collection process normally delete the contents of the session file?

does this setting seem ok though for users that should be logged in until they log off.

Cheers

Walt

dalecosp

My understanding (which is probably wrong, LOL) is that if you have sessions that have been sitting idle for 24 minutes (1440 seconds), there is a one percent likelihood they will be "garbaged" on any script compilation (i.e. subsequent page loads, by anyone).

I wouldn't think this to be an issue unless you're on some very very large site, say cnn.com, etc. that people tend to open and leave open, or some site that contains lengthy media (movies viewed in browser, games, etc.) or long downloads.

Probably you should bump the "max lifetime" a bit if you want to. Remember to restart the server afterwards.

Velausanakha

I too have had this problem.

Its kinda weird when your sessions work without their values, but its only happened to me when hosting locally, on broadcast its always worked fine

also I'm on windows and had sessions set to /tmp, it wasn't causing me any problems at all until I got the empty sessions, so I config'd my php to c:/tmp and I haven't had the problem since

Walt

can I check that when we say session lifetime that does not mean a change to the session file itself but refers to any activity such as loading a new page.

dalecosp

http://www.php.net/manual/en/ref.session.php

It looks as if the file has to be at least "touched" within that lifetime.

session.gc_probability integer

session.gc_probability specifies the probability that the gc (garbage collection) routine is started on each request in percent. Defaults to 1.

session.gc_maxlifetime integer

session.gc_maxlifetime specifies the number of seconds after which data will be seen as 'garbage' and cleaned up.

    Note: If you are using the default file-based session handler, your filesystem must keep track of access times (atime). Windows FAT does not so you will have to come up with another way to handle garbage collecting your session if you are stuck with a FAT filesystem or any other fs where atime tracking is not available. [/i][/quote]

Velausanakha

and I have this problem again

I just upgraded from a 98 machine to an xp machine and I can successfully use my login script but it doesn't carry any further than there, once completed it comes up as an empty session 🙁 help

Velausanakha

and once again I've solved the problem by setting to broadcast but doesn't work for me on localhost

odd that.

anyone got any idea why?