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[RESOLVED] Forum Problems

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As i didn't see a Bugs Forum (maybe good idea to add one :) ) thought id post this what happened after submitting thread also happened during register phase just hitting refresh should fix it. I'm aware your testing new forum software but though should give heads up.

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Mad Penguin:
Interesting .. this is an issue with SMF's caching system .vs. our load balancer.  I have seen it before but thought the last fix dealt with it .. obviously not!

Many thanks for reporting - will look into it.

Mad Penguin:
Ok, the problem seems to stem from SMF caching local sessions on the filesystem. Because the system is load balancing over multiple servers, writes need to flush to the filesystem before the next server tries to read them .. typically this error will show because one server writes preference changes or a post, then calls a redirect to reload the page .. which then typically loads from another server which gets it's read operation in before the back-end has sync'd the write.

I don't think this is down to the filesystem, purely an SMF local caching issue, I'm guessing the local cache isn't calling 'sync' when in this sort of environment it's really not safe to skip it. Anyway, I've just added "memcached" to the PHP servers and added this into the SMF mix .. it seems to have taken and should remove the local SMF cache from the pot .. so  if I'm right, problem solved .. if it happens again, we can discount the local SMF cache.

AND, it should be a little bit quicker because of "memcached" , not that it was slow or anything ... but ... :)

Mark Greaves (PCNetSpec):
He also reported to me that last night he was getting a LOT of page timeouts, I meant to email you but forgot... I wasn't getting any, so the problem may have been at his end.

Mad Penguin:
Timeouts unlikey to be the same issue - this problem will be limited to page refreshes following a write operation.
It won't cause a problem if you're just browsing.


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