Jonathan Moore

no there’s nothing directly related in the Apache logs, but actually I don’t think there’s a request either – I’d already established from some of the logs $_SERVER[‘REQUEST_URI’] etc are not set, hence is from cron call etc

I tried re-enabling without AutoCoupon and then with AutoCoupon and only had one memory blowout in last 5 hours (previously was about every 15min regardless of increasing memory) which was:
PHP Fatal error: Allowed memory size of 201326592 bytes exhausted (tried to allocate 4194304 bytes) in /wp-content/plugins/woocommerce/includes/abstracts/abstract-wc-data.php on line 455
‘value’ => maybe_unserialize( $meta->meta_value ),
.. I can’t find any meta value in the db which could account for 4,194,304 bytes so that remains odd..

I had cleared all transients and user sessions (including shopping carts) from the woocommerce screen, and then gone through applying workarounds to every plugin that was showing any type of minor error.
A corrupted transient / basket seems likely cause of main issue, though exactly how it was triggering any code weakness remains unclear.