[wp-trac] [WordPress Trac] #54221: _transient_dirsize_cache is set to autoload=yes and kills db performance if it grows (20MB in our case)

[WordPress Trac]

#54221: _transient_dirsize_cache is set to autoload=yes and kills db performance if
it grows (20MB in our case)
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 Reporter:  archon810     |       Owner:  (none)
     Type:  defect (bug)  |      Status:  new
 Priority:  normal        |   Milestone:  Future Release
Component:  Database      |     Version:  2.8
 Severity:  major         |  Resolution:
 Keywords:  needs-patch   |     Focuses:  administration, performance
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Comment (by seanconklin):

 I deleted this wp_option row weeks ago and it hasn't returned with the
 latest version of WordPress. In scanning the wp-includes folder I see
 dirsize being called for Multisite as well as WP REST API upload
 functions. It does not appear to be triggering from the Media Library nor
 the Site Health tool.

 Here's a clue I ran into with the client who had this issue. I could tell
 they used to have a Subdirectory installation (where WordPress is served
 from a folder within the site root), because there was an entire copy of
 WordPress plugins and all in a sub-folder that was no longer bring used.
 So the dirsize cache grew large based on all of those folders being left
 behind.

 Object caching is enabled and working fine now. WP Engine recommends an
 800K limit on autoload size and this site used to be several times that!
 They cap the buffer size at 1MB. No wonder object caching was turned off
 until we fixed this. Working great now.

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Ticket URL: <https://core.trac.wordpress.org/ticket/54221#comment:20>
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