Large multisite install: out of memory errors after upgrade to 4.3.3


we upgrade to 4.3.3 yesterday, now when viewing the site list in the Network Admin dashboard we are getting the following fatal error at the time it has to render the top level site information...

PHP Fatal error: Allowed memory size of 268435456 bytes exhausted (tried to allocate 72 bytes) in /var/www/html/wordpress/wp-includes/wp-db.php on line 2125, referer:

We've obviously googled a lot - this doesn't appear to be the split cron bug that affected the 4.3 release (this was patched in the 4.3.1+ releases).

The site list table always stops at the "" top level site at the user count column. The top level site does have a lot of user registered to it - but we never experienced this issue before the upgrade.

Struggling to find anything on this - don't want to just blindly increase memory limit as it's already pretty large - this just masks the problem really.

Need advice!


  • Sajid
    • DEV MAN’s Sidekick

    Hi Paul,

    Hope you are doing good today :slight_smile:

    You upgraded WordPress to 4.3.3 ? I mean if its WordPress then why not upgraded to latest version that is 4.4.2.

    I could not find any error message in our forum except one back in 2013 that also ended up by increasing the memory limit.

    What is the memory right now for you ?

    Take care and have a nice day :slight_smile:
    Cheers, Sajid

  • Paul
    • WPMU DEV Initiate

    Hi Sajid,

    we deliberately lag 1 major version behind for stability reasons - we have 600 sites & 150 plugins on the install - it takes a little while for the developers to get their code in order for newer versions. The 1 major version lag is a principle that has always served us well.

    If this bug is fixed in the newer release we're all good, we'll just wait a release cycle for the fix. But if it's not then I believe it's a bug and may need to be raised on the wordpres trac which I will do later if there are no better ideas coming from this thread.

    This morning we have definitively proved it's a bug in the 4.3.3 release to do with high user counts on a blog (350,000 in this case) - if we add the following filter to remove the user count column from the site list, the error goes away...

    add_filter('wpmu_blogs_columns', function($a){unset($a['users']);return $a;});


  • Paul
    • WPMU DEV Initiate

    Oh and we're at 256M memory - which I'm not wanting to increase just to get a user count working. It feels like WP core has moved to a newer method of generating the user counts on multisite and it's not very well optimised for scale.

Thank NAME, for their help.

Let NAME know exactly why they deserved these points.

Gift a custom amount of points.