WordPress Performance Issue?

♦ Posted by Jeff Starr in PHP, Web Design, WordPress

Updated June 25, 2018 • 27 comments

Just wanted to share a mysterious trend reported for my sites by Google Webmaster Tools, and ask if anyone else is seeing the same pattern. It looks like it’s related to the WordPress 4.4 update, but I’m not 100% sure, so putting the data out there in hopes that others can help shed some light on the issue..

Performance is important. When a site suddenly takes twice as long to load, that could negatively impact its search engine ratings.

From what I can tell, all of my WordPress sites are loading slower across the board, at least for Googlebot. Up until around the beginning of December, most of my WP-powered sites were averaging around 250ms load time for Googlebot. Then suddenly on around the 8th of December, the average load time more than doubled, averaging a little over 500ms for most sites. Here are a few representative screenshots from Google Webmaster Tools:

[ Google Webmaster Tools: PerishablePress.com ]

[ Google Webmaster Tools: htaccessbook.com ]

[ Google Webmaster Tools: Plugin-Planet.com ]

Some of these graphs show the pattern more clearly than others, but the trend is unmistakable: around the beginning of December, WordPress sites require around twice as long to load. I wish I would have taken screenshots about three weeks ago, as the sudden “jump” in load time was much more pronounced and clearly distinguished.

Is it the WordPress?

The thing is, I’ve not made any significant changes that would affect all of my WP sites at the same time, except for updating WordPress to the latest version, 4.4 “Clifford” on December 8th, 2015. So basically my hypothesis is that WordPress 4.4 takes around twice as long to load on my server, according to Google.

To serve as a baseline for comparison, here are the data for one of my sites that is not running WordPress:

[ Google Webmaster Tools: Monzilla Media ]

Notice that, apart from the outlier data, the load-time performance remains consistently low throughout the entire time duration. No sudden jump after the beginning of December. This points to the issue being related to the WordPress update, in my opinion.

So is anyone else seeing similar data? Any alternate hypotheses besides it being WordPress? If not, what major changes were introduced in WP 4.4 that may account for the sudden jump in load time? Couldn’t be the new REST API stuff, could it?

To be crystal clear: I’m just hypothesizing slash thinking out loud on this one.. NOT saying for sure it’s anything this or that, just pointing out what I’m seeing in the data, and trying to make sense of it, in order to find a solution. As mentioned above, a doubling of load time is not a good thing.

Any insight is appreciated.

Update: Read the thrilling conclusion to this WordPress-performance mystery!

google performance

About the Author

Jeff Starr = Web Developer. Security Specialist. WordPress Buff.

27 responses to “WordPress Performance Issue?”

Brandon 2016/02/22 5:03 pm

It might be useful to list the plugins and themes you are using across the sites. Its very well that you have one plugin or theme used on all the sites that runs slower with version 4.4.

Jeff Starr 2016/02/22 5:32 pm • Post Author

Good point, but there are no plugins in common across all sites. Also all themes are unique, custom builds.

Pace 2016/02/22 9:10 pm

Do they all run jetpack? Connected to your WP.com account?

Jeff Starr 2016/02/22 9:19 pm • Post Author

Another good idea, but no — I’ve never used Jetpack, and none of my sites are connected to my WordPress.com account.. but that does beg the question if there is something that happened to Jetpack/WP.com performance-wise around the same timeframe..?

Kristian 2016/02/22 11:17 pm

Checked 9 of my sites, if anything my times have gone down like 5%.

Jeff Starr 2016/02/22 11:48 pm • Post Author

Can you post screenshots of some of them? (the graphs)
- Kristian 2016/02/23 12:00 am
  
  Just temporarily uploaded them here
  
  http://roka.se/2016/02/some-site-statistics/
  
  Let me know when you’ve looked at them so I can take them down again.
- Jeff Starr 2016/02/23 12:09 am • Post Author
  
  Got em, thanks. And yeah, if those are WP sites it doesn’t look like they are affected by whatever it is slowing things down on my server.. which is interesting but serves only to deepen the mystery.
- Kristian 2016/02/23 12:51 am
  
  Yep, WP on Dig Ocean VPSs and ServerPilot via CloudFlare
- Jeff Starr 2016/02/23 1:01 am • Post Author
  
  Cool, do you know which version of PHP you are running?
- Kristian 2016/02/23 10:23 pm
  
  PHP at 5.6.18
  Ubuntu 14.04.4

Joan 2016/02/22 11:44 pm

Same server across all sites too?

Jeff Starr 2016/02/22 11:47 pm • Post Author

Yes, (mt) VPS
- Joan 2016/02/22 11:54 pm
  
  Just wondering if it’s some server configuration. Media Temple are pretty good though… PHP7?
  
  Can you take a look at another site on another hosting company? A client, maybe?
  
  I have clients on SiteGround, Pagely and WP-Engine, and I haven’t noticed that performance issue.
- Jeff Starr 2016/02/23 12:12 am • Post Author
  
  Yeah all on the same box with same server configuration, etc. Running a version of PHP < 7.
  
  Next time I can get to a client’s Webmaster Tools account, I’ll definitely take a look.. in the meantime I am hoping that readers will share what they are seeing (as Kristian generously has done).
  
  It’s the coincidence that has me scratching my head, although I’ll be the first to admit some other variable could be at play.

Connie 2016/02/23 12:22 am

my experience is that ALL wordpress-installations at one of my servers are going slower and slower, especially slow in the backend.

It seems that the reason for this is un outdated PHP-version, after updating PHP from 5.3.7 to 5.6.1 (if I remember right), the same installation got noticeable faster with PHP 5.6.1 (switching versions with addhandler-directive in .htaccess)

so have a look at this!

Jeff Starr 2016/02/23 12:34 am • Post Author

Nice infos. That very well could be it.. WP is geared more toward newer versions of PHP, so some functionality may be stumbling a bit over older PHP versions..? (just a guess at why it could be a PHP version issue)

Question: when you updated your PHP, why did you find it necessary to use .htaccess to switch things up (via addhandler), rather than just run everything on the newer PHP?

Connie 2016/02/23 3:05 am

well as we were not sure whether it is a common problem or not and we wanted to test with one installation on the server we choose the addhandler-method

by this the other active WP-installations were not harmed by the testing process and I can switch installation one by one. That gives me the chance to debug and identify deprecated functions etc. in the plugins of each installation…

Connie 2016/02/23 3:07 am

I forgot to add that it is running with PHP 5.6.1 now (don’t ask me why the technician upgraded to that version), but it is definite a performance boost
Jeff Starr 2016/02/23 9:52 am • Post Author

Alright awesome, thanks for the information Connie, very helpful.

lizzyfin 2016/02/23 4:31 am

Hey Jeff,
I feel like a rank beginner with WP compared to y’all so that’s why I pay attention to the things you write and share. Thanks, BTW!

When comparing the graphs you can’t just eyeball it and “see” that the apparent differences of download times are significant. In this case the comparison is muddled by the fact that the vertical axes are not all the same. If you could reconstruct the graph for monzillamedia.com you might just see the same increase in download times. The line is flat in the beginning of December, then there’s slight rise. Doesn’t appear to be significant, but the X-axis is condensed about 6X compared to the others.

There may well be a newly introduced lag time (experienced by all the sites?), but this type of comparison is virtually meaningless to the scientist in me.

If the data used to create the graphs are available, the differences between the curves on the graphs could be determined with some effort.

Jeff Starr 2016/02/23 1:24 pm • Post Author

That could be the case, unfortunately Google Webmaster Tools pretty much provides one set of data in graph form, with no way to manipulate, etc. Otherwise, I would have equalized the Y axes and broadened the X axes for greater duration.

It is clear that something changed on my WP sites around the same time, and that now they are taking about twice as long to load for Googlebot. Personally I have not noticed any difference, but if Google is seeing it, they’re gonna react however they see fit.

Jeroen 2016/02/23 6:16 pm

Here some more. All on MDD shared hosting except the last one. That’s on a crappy Indonesian host called Jagoan.

http://s12.postimg.org/57rpal0l9/Image9.gif

Jeroen 2016/02/23 6:18 pm

Apache Version 2.4.18
PHP Version 5.6.17
- Jeff Starr 2016/02/23 9:05 pm • Post Author
  
  Thanks Jeroen, it’s looking more and more like an issue running WP with older versions of PHP (i.e., PHP < 5.6)
- Jeroen 2016/02/24 2:28 am
  
  The server of the last image has the following
  
  Apache Version 2.4.12
  PHP Version 5.4.41
  
  And that’s the only one with the same problem as your sites, so you could be right.
- Jeff Starr 2016/02/24 9:00 am • Post Author
  
  That’s what I’m thinking. Gonna maybe try updating to PHP 7 today and see what happens over the next few weeks. Will report back once Googlebot provides some data.
  
  Update: just went with PHP 5.6 for the sake of saving time.. switching several of my WP sites over now, will report back in a few weeks with the results.

Comments are closed for this post. Something to add? Let me know.

Brandon 2016/02/22 5:03 pm

It might be useful to list the plugins and themes you are using across the sites. Its very well that you have one plugin or theme used on all the sites that runs slower with version 4.4.
- Jeff Starr 2016/02/22 5:32 pm • Post Author
  
  Good point, but there are no plugins in common across all sites. Also all themes are unique, custom builds.
Pace 2016/02/22 9:10 pm

Do they all run jetpack? Connected to your WP.com account?
- Jeff Starr 2016/02/22 9:19 pm • Post Author
  
  Another good idea, but no — I’ve never used Jetpack, and none of my sites are connected to my WordPress.com account.. but that does beg the question if there is something that happened to Jetpack/WP.com performance-wise around the same timeframe..?
Kristian 2016/02/22 11:17 pm

Checked 9 of my sites, if anything my times have gone down like 5%.
- Jeff Starr 2016/02/22 11:48 pm • Post Author
  
  Can you post screenshots of some of them? (the graphs)
  - Kristian 2016/02/23 12:00 am
    
    Just temporarily uploaded them here
    
    http://roka.se/2016/02/some-site-statistics/
    
    Let me know when you’ve looked at them so I can take them down again.
  - Jeff Starr 2016/02/23 12:09 am • Post Author
    
    Got em, thanks. And yeah, if those are WP sites it doesn’t look like they are affected by whatever it is slowing things down on my server.. which is interesting but serves only to deepen the mystery.
  - Kristian 2016/02/23 12:51 am
    
    Yep, WP on Dig Ocean VPSs and ServerPilot via CloudFlare
  - Jeff Starr 2016/02/23 1:01 am • Post Author
    
    Cool, do you know which version of PHP you are running?
  - Kristian 2016/02/23 10:23 pm
    
    PHP at 5.6.18
    Ubuntu 14.04.4
Joan 2016/02/22 11:44 pm

Same server across all sites too?
- Jeff Starr 2016/02/22 11:47 pm • Post Author
  
  Yes, (mt) VPS
  - Joan 2016/02/22 11:54 pm
    
    Just wondering if it’s some server configuration. Media Temple are pretty good though… PHP7?
    
    Can you take a look at another site on another hosting company? A client, maybe?
    
    I have clients on SiteGround, Pagely and WP-Engine, and I haven’t noticed that performance issue.
  - Jeff Starr 2016/02/23 12:12 am • Post Author
    
    Yeah all on the same box with same server configuration, etc. Running a version of PHP < 7.
    
    Next time I can get to a client’s Webmaster Tools account, I’ll definitely take a look.. in the meantime I am hoping that readers will share what they are seeing (as Kristian generously has done).
    
    It’s the coincidence that has me scratching my head, although I’ll be the first to admit some other variable could be at play.
Connie 2016/02/23 12:22 am

my experience is that ALL wordpress-installations at one of my servers are going slower and slower, especially slow in the backend.

It seems that the reason for this is un outdated PHP-version, after updating PHP from 5.3.7 to 5.6.1 (if I remember right), the same installation got noticeable faster with PHP 5.6.1 (switching versions with addhandler-directive in .htaccess)

so have a look at this!
- Jeff Starr 2016/02/23 12:34 am • Post Author
  
  Nice infos. That very well could be it.. WP is geared more toward newer versions of PHP, so some functionality may be stumbling a bit over older PHP versions..? (just a guess at why it could be a PHP version issue)
  
  Question: when you updated your PHP, why did you find it necessary to use .htaccess to switch things up (via addhandler), rather than just run everything on the newer PHP?
Connie 2016/02/23 3:05 am

well as we were not sure whether it is a common problem or not and we wanted to test with one installation on the server we choose the addhandler-method

by this the other active WP-installations were not harmed by the testing process and I can switch installation one by one. That gives me the chance to debug and identify deprecated functions etc. in the plugins of each installation…
- Connie 2016/02/23 3:07 am
  
  I forgot to add that it is running with PHP 5.6.1 now (don’t ask me why the technician upgraded to that version), but it is definite a performance boost
- Jeff Starr 2016/02/23 9:52 am • Post Author
  
  Alright awesome, thanks for the information Connie, very helpful.
lizzyfin 2016/02/23 4:31 am

Hey Jeff,
I feel like a rank beginner with WP compared to y’all so that’s why I pay attention to the things you write and share. Thanks, BTW!

When comparing the graphs you can’t just eyeball it and “see” that the apparent differences of download times are significant. In this case the comparison is muddled by the fact that the vertical axes are not all the same. If you could reconstruct the graph for monzillamedia.com you might just see the same increase in download times. The line is flat in the beginning of December, then there’s slight rise. Doesn’t appear to be significant, but the X-axis is condensed about 6X compared to the others.

There may well be a newly introduced lag time (experienced by all the sites?), but this type of comparison is virtually meaningless to the scientist in me.

If the data used to create the graphs are available, the differences between the curves on the graphs could be determined with some effort.
- Jeff Starr 2016/02/23 1:24 pm • Post Author
  
  That could be the case, unfortunately Google Webmaster Tools pretty much provides one set of data in graph form, with no way to manipulate, etc. Otherwise, I would have equalized the Y axes and broadened the X axes for greater duration.
  
  It is clear that something changed on my WP sites around the same time, and that now they are taking about twice as long to load for Googlebot. Personally I have not noticed any difference, but if Google is seeing it, they’re gonna react however they see fit.
Jeroen 2016/02/23 6:16 pm

Here some more. All on MDD shared hosting except the last one. That’s on a crappy Indonesian host called Jagoan.

http://s12.postimg.org/57rpal0l9/Image9.gif
- Jeroen 2016/02/23 6:18 pm
  
  Apache Version 2.4.18
  PHP Version 5.6.17
  - Jeff Starr 2016/02/23 9:05 pm • Post Author
    
    Thanks Jeroen, it’s looking more and more like an issue running WP with older versions of PHP (i.e., PHP < 5.6)
  - Jeroen 2016/02/24 2:28 am
    
    The server of the last image has the following
    
    Apache Version 2.4.12
    PHP Version 5.4.41
    
    And that’s the only one with the same problem as your sites, so you could be right.
  - Jeff Starr 2016/02/24 9:00 am • Post Author
    
    That’s what I’m thinking. Gonna maybe try updating to PHP 7 today and see what happens over the next few weeks. Will report back once Googlebot provides some data.
    
    Update: just went with PHP 5.6 for the sake of saving time.. switching several of my WP sites over now, will report back in a few weeks with the results.