[wp-trac] [WordPress Trac] #44818: cron: preventing duplicate events fails when the first event is too far in the past

[WordPress Trac]

#44818: cron: preventing duplicate events fails when the first event is too far in
the past
-----------------------------+------------------------------
 Reporter:  bodohugobarwich  |       Owner:  (none)
     Type:  defect (bug)     |      Status:  new
 Priority:  normal           |   Milestone:  Awaiting Review
Component:  Cron API         |     Version:  2.7
 Severity:  normal           |  Resolution:
 Keywords:  needs-patch      |     Focuses:
-----------------------------+------------------------------
Description changed by SergeyBiryukov:

Old description:

> the patch submitted in \\
> [https://core.trac.wordpress.org/changeset/29939]\\
> [https://core.trac.wordpress.org/ticket/6966]\\
> fails when the timestamp of the first event is too far in the past,
> perhaps because the cron was not executed.
>
> in src/wp-includes/cron.php :
>

> {{{
> if ( $next && abs( $next - $timestamp ) <= 10 * MINUTE_IN_SECONDS ) {
>         return;
> }
>
> }}}
>
> The same Event that has been scheduled in 2016 and was not processed
> since then
> permits that any amount of those Events can be added in 1 second
> interval.
>
> That way the database field "cron" in "wp_options" fills up with
> "do_ping" Events in 1 second interval until no further event can't be
> added due to MySQL packet_size restrictions.
>

>
> {{{
> $ date --date="1970-01-01 + 1464704077 sec" +"%F %T"
> 2016-05-31 15:14:37
>
> $ php -r "echo abs( 1464704077 - time()) . \"\\n\";"
> 69813398
> $ php -r "echo abs( 1464704077 - time()) . \" < \". (10*600) . \"\\n\";"
> 69813460 < 6000
> $ php -r "echo (1464704077 - time()) . \" < \". (10*600) . \"\\n\";"
> -69813728 < 6000
> }}}

New description:

 the patch submitted in [29939]/#6966 fails when the timestamp of the first
 event is too far in the past, perhaps because the cron was not executed.

 in src/wp-includes/cron.php :


 {{{
 if ( $next && abs( $next - $timestamp ) <= 10 * MINUTE_IN_SECONDS ) {
         return;
 }

 }}}

 The same Event that has been scheduled in 2016 and was not processed since
 then
 permits that any amount of those Events can be added in 1 second interval.

 That way the database field "cron" in "wp_options" fills up with "do_ping"
 Events in 1 second interval until no further event can't be added due to
 MySQL packet_size restrictions.



 {{{
 $ date --date="1970-01-01 + 1464704077 sec" +"%F %T"
 2016-05-31 15:14:37

 $ php -r "echo abs( 1464704077 - time()) . \"\\n\";"
 69813398
 $ php -r "echo abs( 1464704077 - time()) . \" < \". (10*600) . \"\\n\";"
 69813460 < 6000
 $ php -r "echo (1464704077 - time()) . \" < \". (10*600) . \"\\n\";"
 -69813728 < 6000
 }}}

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Ticket URL: <https://core.trac.wordpress.org/ticket/44818#comment:10>
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