brockangelo

This plugin schedules a daily event using wp_cron that deletes all comments marked “spam” in the database, then optimizes the comments table.
Brief reason why I made such a low-tech plugin:
Akismet catches all the spam, but when I was looking at the size of my backups one day, 
I noticed that there were large numbers of comment spam across several sites that were undeleted and they 
made the databases fairly large. So I setup a cron job on my server that deletes the spam.
Since I had never written a plugin, I thought this might be helpful for those who do not have 
a dedicated server, shell access to their site, or the knowledge of (or interest in ) cron to set this up.
Spam is not deleted until you start the schedule after the plugin is activated. I created buttons 
to start and stop the schedule if you need that layer of control. There is also a button for deleting all spam manually.

Delete Spam Daily

Uses wp_cron to delete comments each day that are marked "spam" in the database.

Kuba Mikita

BracketSpace

Take full control of your WordPress cron system. Advanced Cron Manager gives you complete visibility into every scheduled task running on your site — so you can find problems, fix them, and keep your site running smoothly.
WordPress relies on WP-Cron for critical background tasks: sending emails, publishing scheduled posts, running backups, syncing data, and more. But by default, you have zero visibility into what’s happening. Events fail silently, schedules pile up, and debugging is guesswork. Advanced Cron Manager changes that.
What you can do with the free version:
<ul>
<li>See every scheduled event — view all registered cron events with their hooks, arguments, schedules, and next execution times, all in one clean dashboard</li>
<li>Search and filter — quickly find the event you’re looking for, even on sites with hundreds of cron jobs</li>
<li>Run events manually — trigger any cron event on demand to test it or force an immediate execution</li>
<li>Pause and resume events — temporarily disable events without losing their configuration, perfect for troubleshooting</li>
<li>Add and remove events — create new cron events or unschedule ones you no longer need</li>
<li>Copy-paste PHP implementation — get ready-to-use code snippets for each event’s action hook and callback</li>
<li>Bulk actions — manage multiple events at once: remove, pause, or unpause in batch</li>
<li>Manage schedules — view, add, edit, and remove custom cron schedules (intervals)</li>
<li>Server Scheduler — disable WP-Cron’s default page-load triggering and get instructions for setting up a real server cron job for more reliable execution</li>
</ul>
<h4>Advanced Cron Manager PRO</h4>
The free version shows you what’s scheduled. PRO shows you what actually happened.
Without logging and diagnostics, cron issues are invisible until something breaks. PRO gives you the tools to monitor, debug, and optimize every cron job on your site.
<ul>
<li>Cron Logger — full execution history with timestamps and status for every event. Know exactly what ran, when it ran, and whether it succeeded or failed.</li>
<li>Performance Stats — execution time and peak memory usage tracked per event. Spot slow or resource-heavy cron jobs before they become a problem.</li>
<li>Error Catcher — automatically catches fatal errors thrown by cron callbacks and displays them in the log. No more silent failures.</li>
<li>Debug Tool — log custom data from inside your cron callbacks using <code>do_action('advanced-cron-manager/log')</code>. Get full visibility into what your code is doing during cron execution.</li>
<li>Event Rescheduling — change the next execution date and schedule of any event. Shift heavy tasks away from peak hours to balance server load.</li>
<li>Event Listeners — see every function and method hooked into each cron event. Understand exactly what code runs behind each hook.</li>
<li>Advanced Scheduling (Schyntax) — go beyond simple intervals. Schedule events for specific times like noon on the last day of the month, only on weekdays, every Tuesday and Friday, and more.</li>
</ul>
14-day money-back guarantee — no risk, no questions asked.
<a href="https://bracketspace.com/downloads/advanced-cron-manager-pro/?utm_source=wporg&utm_medium=readme&utm_campaign=readme" title="Advanced Cron Manager PRO" rel="nofollow ugc">Get Advanced Cron Manager PRO</a>
<h4>Good to know about WP-Cron</h4>
WordPress Cron is triggered by page visits, which means scheduled tasks may not run exactly on time on low-traffic sites. For precise timing, use the Server Scheduler feature to set up a real system cron job. Note: custom schedules added by this plugin are only available while the plugin is active. Events you create will continue to exist after deactivation.
<h4>Custom Development</h4>
BracketSpace — the company behind this plugin — provides <a href="https://bracketspace.com/custom-development/" rel="nofollow ugc">custom WordPress plugin development services</a>. We can build any custom plugin for you.

Advanced Cron Manager – debug & control

Thank you for this plugin. I'm liking it better than what I used to use. Excellent interface.

Delete Spam Daily vs Advanced Cron Manager – debug & control