From 6a301a1bf5b432ee8c0cca853ce63f04f8a582aa Mon Sep 17 00:00:00 2001 From: Guewen Baconnier Date: Wed, 14 Aug 2019 12:04:47 +0200 Subject: [PATCH] [10.0] Remove RowExclusiveLock on exception_rule The goal of the modified method is to create or remove the relationship (in the M2m relation tabel) between the tested model (such as sale_order) and the exception rules. When the ORM writes on ExceptionRule.sale_ids (using the example of sale_exception), it will first proceeds with these updates: * an UPDATE on exception_rule to set the write_date * INSERT or DELETE on the relation table * but then, as "write" is called on the exception rule, the ORM will trigger the api.depends to recompute all the "main_exception_ids" of the records (sales, ...) related to it, leading to an UPDATE for each sale order We end up with RowExclusiveLock on such records: * All the records of the relation table added / deleted for the current sale order * All the records of exception_rule matching the current sale order * All the records of sale_order related to the exception rules matching the current sale order The first one is expected, the next 2 are not. We can remove the lock on the exception_rule table by removing `_log_access`, however in any case, the main_exception_ids computed field will continue to lock many sale orders, effectively preventing 2 sales orders with the same exception to be confirmed at the same time. Reversing the write by writing on SaleOrder instead of ExceptionRule fixes the 2 unexpected locks. It should not result in more queries: the "to remove" part generates a DELETE on the relation table for the rule to remove and the "to add" part generates an INSERT for the rule to add, both will be exactly the same in both cases. Related to #1642 Replaces #1638 --- base_exception/models/base_exception.py | 29 ++++++++++++++++++++++--- 1 file changed, 26 insertions(+), 3 deletions(-) diff --git a/base_exception/models/base_exception.py b/base_exception/models/base_exception.py index 42de521a8..3c577ee56 100644 --- a/base_exception/models/base_exception.py +++ b/base_exception/models/base_exception.py @@ -103,6 +103,8 @@ class BaseExceptionMethod(models.AbstractModel): rules = self.env['exception.rule'].sudo().search( self._rule_domain()) all_exception_ids = [] + rules_to_remove = {} + rules_to_add = {} for rule in rules: records_with_exception = self._detect_exceptions(rule) reverse_field = self._reverse_field() @@ -110,11 +112,32 @@ class BaseExceptionMethod(models.AbstractModel): commons = main_records & rule[reverse_field] to_remove = commons - records_with_exception to_add = records_with_exception - commons - to_remove_list = [(3, x.id, _) for x in to_remove] - to_add_list = [(4, x.id, _) for x in to_add] - rule.write({reverse_field: to_remove_list + to_add_list}) + # we expect to always work on the same model type + rules_to_remove.setdefault( + rule.id, main_records.browse() + ).update(to_remove) + rules_to_add.setdefault( + rule.id, main_records.browse() + ).update(to_add) if records_with_exception: all_exception_ids.append(rule.id) + # Cumulate all the records to attach to the rule + # before linking. We don't want to call "rule.write()" + # which would: + # * write on write_date so lock the expection.rule + # * trigger the recomputation of "main_exception_id" on + # all the sale orders related to the rule, locking them all + # and preventing concurrent writes + # Reversing the write by writing on SaleOrder instead of + # ExceptionRule fixes the 2 kinds of unexpected locks. + # It should not result in more queries than writing on ExceptionRule: + # the "to remove" part generates one DELETE per rule on the relation + # table and the "to add" part generates one INSERT (with unnest) per + # rule. + for rule_id, records in rules_to_remove.iteritems(): + records.write({'exception_ids': [(3, rule_id,)]}) + for rule_id, records in rules_to_add.iteritems(): + records.write(({'exception_ids': [(4, rule_id,)]})) return all_exception_ids @api.model