[wp-trac] [WordPress Trac] #21098: Out of memory errors in XML-RPC

[WordPress Trac]

#21098: Out of memory errors in XML-RPC
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 Reporter:  koke                 |       Owner:
     Type:  defect (bug)         |      Status:  new
 Priority:  normal               |   Milestone:  Awaiting Review
Component:  XML-RPC              |     Version:  3.4
 Severity:  major                |  Resolution:
 Keywords:  mobile dev-feedback  |
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Comment (by maxcutler):

 It turns out that most of the memory usage comes from the `include`'d code
 and not the actual data being acted upon (unless you request an extremely
 large number of items).

 Example: On my machine, after `wp-load.php` is `include`'d, the memory
 usage is about 23MB. `xmlrpc.php` then `include`s `wp-
 admin/includes/admin.php`, `class-IXR.php`, and `class-wp-xmlrpc-
 server.php` which boosts memory usage up to ~30MB. Most typical XML-RPC
 methods only add 0.5-1.5 MB on top of that.

 If you look, `wp-admin/includes/admin.php` actually loads a bunch of other
 files. This is needed because the server uses `has_meta`,
 `wp_generate_attachment_metadata`, `wp_create_category` and similar
 methods. You can cut memory usage by half (7MB→3.5MB) by only including
 `wp-admin/includes/{post,taxonomy,image}.php`. We could save even more if
 the needed functions were moved elsewhere and we could avoid the other
 code in those files (e.g., `post.php` is pretty large).

 By comparison, removing all of the legacy methods (everything not in the
 wp.* namespace) only saves about 0.7MB.

 So if we could either move functions around so less code has to be
 `include`'d or else change which functions we use in the XML-RPC server,
 then we could potentially save substantial amounts of memory. And there
 are probably memory savings to be had in that 23MB baseline from the load
 process, but that's for another ticket.

-- 
Ticket URL: <http://core.trac.wordpress.org/ticket/21098#comment:13>
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