How to prevent lock wait timeout from blocking orders?

Question

Got a lock wait timeout originating in Mage_Sales_Model_Order::_afterSave(): https://github.com/LokeyCoding/magento-mirror/blob/magento-1.8/app/code/core/Mage/Sales/Model/Order.php#L2152

Looks like it's due to a reporting query that was running for a very long time and keeping the lock for a long time:

INSERT INTO `sales_order_aggregated_updated` (`period`, `store_id`, `order_status`, `orders_count`, `total_qty_ordered`, `total_qty_invoiced`, `total_income_amount`, `total_revenue_amount`, `total_profit_amount`, `total_invoiced_amount`, `total_canceled_amount`, `total_paid_amount`, `total_refunded_amount`, `total_tax_amount`, `total_tax_amount_actual`, `total_shipping_amount`, `total_shipping_amount_actual`, `total_discount_amount`, `total_discount_amount_actual`, `exchanges`, `gifts`)
...

Haven't dug into it much yet, was thinking I should post up a question before diving in. My inclination is to just disable the report aggregation crons entirely and rely on simple order queries (a la Aheadworks Advanced Reports) for reporting.

Answer 1

What I ended up doing was just disabling these reporting crons. Using something like Aheadworks Advanced Reports for reporting or Custom Reports is a lot more manageable in my case.

Answer 2

Magento doesn't properly encapsulate transactions in MySQL, leading to errors such as these. Try setting the session transaction isolation level in MySQL to SERIALIZABLE.