Spike: Slow response time on subscriptions order screen #761
Description
Performance Details
On larger sites, the subscriptions orders page in the admin is among the discovered slower (>2s) requests. See p2-pcShBQ-2J3 for more details.
Request: /wp-admin/admin.php?page=wc-orders--shop_subscription
Average Time: 13.59s
Affected Sites
This appears to affect sites that use subscriptions (either from WooPayments or WooCommerce Subscriptions) and most likely those that have more orders and/or more subscriptions.
The sample size for sites with this subscriptions performance issue is relatively small, but the issue does appear to happen in the 10,000 - 100,000 completed orders range.
Suspected Causes
It's very likely that this is related to the main orders count query performance issues, but this should be confirmed.
This should be tested with a site with many subscriptions and subscription orders. The specific VIP sites may need to be cloned to diagnose the exact cause and ensure all slow queries are caught.