Performance hit on 2.5 upgrade for admin users

Performance hit on 2.5 upgrade for admin users

by John Porten -
Number of replies: 8

We recently updated a number of sites from 2.4 to 2.5.   We are experiencing a severe response time degradation on the 2.5 site when logged in as an admin user.   

In fact, simply logging in as an admin can take as long at 30 seconds.   Logging in on a 2.4 site on same infrastructure is lightning fast.

One big issue we noticed is that the plugin info cache is being rebuilt and rewritten on every page when logged in as an admin.   Non-admin users are fine.   

Anyone else seeing this behavior?

This tracker caught our attention, but we have dug into it enough tell if this is helping or hurting: https://tracker.moodle.org/browse/MDL-34401

I would be happy to provide links our our test sites if anyone is interested.

 

Average of ratings: Useful (1)
In reply to John Porten

Re: Performance hit on 2.5 upgrade for admin users

by John Porten -

So,  the 2.4 and 2.5 sites referenced above are running on the same infrastructure...  4 app nodes (centos 6.4), load balancer, db server.  

We have a another 2.5 site, recently upgraded from 2.4, running on separate centos server.   No problems on this site.    

Very strange...

I probably should have mentioned in the original post that the 2.4 and 2.5 sites are clean installs with a couple demo courses loaded.   

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In reply to John Porten

Re: Performance hit on 2.5 upgrade for admin users

by Simon Trendell -

I am certainly seeing something similar with 2.5 although it only seems to affect the administrator role on the front page, all other pages load reasonably well and the cache seems effective.

As you say, on my front page the plugin info caches seem to get rewritten every page load, although the same cache on all other pages is fine.

We have both Linux & Windows installations to test on and it happens on both environments, Linux copes a little better with all the filesystem activity so the effect is less noticeable.

I've attached the cache info screenshots for an admin in a course and the front page. Hopefully if others are seeing the same thing it's an issue rather than a problem with our setup.

 

Attachment Course.JPG
Attachment FrontPage.JPG
Average of ratings: Useful (1)
In reply to Simon Trendell

Re: Performance hit on 2.5 upgrade for admin users

by Haakon Meland Eriksen -

FINALLY! Thank you guys for pinning this one down! smile

I have been put off from creating new content and bringing on more users to my 2.5 site for months, moved from one server to another, pestering my hosting company and so on, but no improvement was found.

I had noticed that it was mostly the front page and when turning on editing, and had turned off everything - blocks, lists you name it. However, as this was an empty site, I really had not thought of this being tied to the admin user, but thanks to you I can now confirm that other roles do have this problem, only the admin role or admin user - I have not checked this.

Do we need a new bug for this, or will the one mentioned above do the trick?

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In reply to Haakon Meland Eriksen

Svar: Re: Performance hit on 2.5 upgrade for admin users

by Haakon Meland Eriksen -

Gah! "other roles do have this problem" should have been "other roles do not have this problem".clown

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In reply to Simon Trendell

Re: Performance hit on 2.5 upgrade for admin users

by Juergen Zimmer -

Dear Simon, may I ask how you got this cache info on your page? I searched in the admin settings and googled a bit but couldn't find the right setting.

 

Thanks

  jzimmer

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In reply to Juergen Zimmer

Re: Performance hit on 2.5 upgrade for admin users

by Guillermo Madero -

Hi Juergen,

You can find it at Administration > Development > Debugging, Performance info.

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In reply to John Porten

Re: Performance hit on 2.5 upgrade for admin users

by Howard Miller -
Picture of Core developers Picture of Documentation writers Picture of Particularly helpful Moodlers Picture of Peer reviewers Picture of Plugin developers

What's the machine doing when ad admin logs in? I assume you have some sort of monitoring - if not you should? Even just watching 'top' is a good start. 

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