Thread

I’ve been running several EE 2.x sites for a year or so now, and
have just recently wanted to start using the WIKI module.

I’ve been trying to get started but keep running into a rather toxic issue.

I’ve been following the “first-time setup” instructions in the wiki module documentation.
Install the module, create a template group, add the tag to the index template, and so on.

When I access the page, it displays fine. As soon as I try to do anything, however, even if it’s only to edit the default text in the sample page, then “something” happens.
The page never changes, but my SQL server loads start to climb until after about two minutes loads are so high that the machine is no longer responsive and needs a brutal, hard reset.

I’m not seeing any hints of error conditions any where, so I don’t even know where to start looking.

Has this happened to anybody else before? Anybody have any tips as to where I can start looking for problems?

I’ve just upgraded from 2.4 to 2.5.2, and the condition exists in both versions. My SQL server is on a separate machine, if that plays any role at all.

Any help is greatly appreciated!

Andy

Hi Andy Kelly,

That is certainly odd! Have you made any changes to the default Wiki theme?

Did you see this notice in the User Guide?

Do not enable caching on the template containing the Wiki module tag.

Can you check that caching is disabled on the wiki template?

Cheers,

Hi Dan,

no, it’s all default, right out of the box. I haven’t done anything at all
other than fire up the default as per the user documentation.

And caching is definitely not active.

[added 17 Aug]

Can anybody give me some hints as to where to look? Which log files can or should contain info?
Anything?

Andy

Hi Andy,

It may be best if we get a look first hand. Be on the lookout for an email from EllisLab.

~

Hi Dan,

many thanks for this. I’ve received the mail(s); will be responding within the hour.

Andy

All -

We’re working with Andy privately to resolve this. Once we have the solution, we’ll post back here to share with the group!

~

Dear all,

this issue has been resolved and we couldn’t be more happy!

I’m going to leave it to one of the EE team to describe the discovered
problem and the solution, and just simply say, Dan, Kevin, thank
you very, very much.

Andy

Thanks Andy!

This was a strange one, but we tracked it down to this bug, which would cause garbage collection (the automatic clearing of caches and old lines from the DB) to fail to run if Online User Tracking is disabled. This caused this particular site’s exp_security_hashes table to grow to an incredible 15.5 million rows. That’s 1.9GB. And that caused the site to stall when trying to perform a complex query, like the one performed when submitting the edit form on a wiki page.

The solution was to first run this against the database to clear the table:

TRUNCATE exp_security_hashes;

Then apply the bug fix linked above. If you don’t truncate the table before applying the bug fix, you might see your site stall on the first page load after the fix is applied. Not good.

Glad we could wrap this one up!