Change Details

``` adam@adsh git/gerrit/mediawiki ((f4bf52e...)) $ php ./maintenance/eval.php > ObjectCache::getMainWANInstance(); Fatal error: Out of memory (allocated 1413480448) (tried to allocate 262144 bytes) in git\gerrit\mediawiki\includes\db\loadbalancer\LoadBalancer.php on line 121 Fatal error: Out of memory (allocated 1413480448) (tried to allocate 262144 bytes) in Unknown on line 0 ``` It looks like with a setting of CACHE_ANYTHING as the cache maintype and mysql as the db backend something like the below happens: # Call ObjectCache::getMainWANInstance(); # ObjectCache::newAnything is called to get a cache which tries to use a db backend as a cache (MediaWikiServices::getInstance()->getDBLoadBalancer()) # The service wiring for DBLoadBalancerFactory is called which returns a new LoadBalancer instance # LoadBalancer::__construct again calls ObjectCache::getMainWANInstance(); This is as a result of https://gerrit.wikimedia.org/r/#/c/300493/ This also results in any attempt to load any pages failing. git bisect shows that the above patch caused the issue.

``` adam@adsh git/gerrit/mediawiki ((f4bf52e...)) $ php ./maintenance/eval.php > ObjectCache::getMainWANInstance(); Fatal error: Out of memory (allocated 1413480448) (tried to allocate 262144 bytes) in git\gerrit\mediawiki\includes\db\loadbalancer\LoadBalancer.php on line 121 Fatal error: Out of memory (allocated 1413480448) (tried to allocate 262144 bytes) in Unknown on line 0 ``` It looks like with a setting of CACHE_ANYTHING as the cache maintype and mysql as the db backend something like the below happens: # Call ObjectCache::getMainWANInstance(); # ObjectCache::newAnything is called to get a cache which tries to use a db backend as a cache (MediaWikiServices::getInstance()->getDBLoadBalancer()) # The service wiring for DBLoadBalancerFactory is called which returns a new LoadBalancer instance # LoadBalancer::__construct again calls ObjectCache::getMainWANInstance(); This is as a result of https://gerrit.wikimedia.org/r/#/c/300493/ which fixed T24923 This also results in any attempt to load any pages failing. git bisect shows that the above patch caused the issue.

``` adam@adsh git/gerrit/mediawiki ((f4bf52e...)) $ php ./maintenance/eval.php > ObjectCache::getMainWANInstance(); Fatal error: Out of memory (allocated 1413480448) (tried to allocate 262144 bytes) in git\gerrit\mediawiki\includes\db\loadbalancer\LoadBalancer.php on line 121 Fatal error: Out of memory (allocated 1413480448) (tried to allocate 262144 bytes) in Unknown on line 0 ``` It looks like with a setting of CACHE_ANYTHING as the cache maintype and mysql as the db backend something like the below happens: # Call ObjectCache::getMainWANInstance(); # ObjectCache::newAnything is called to get a cache which tries to use a db backend as a cache (MediaWikiServices::getInstance()->getDBLoadBalancer()) # The service wiring for DBLoadBalancerFactory is called which returns a new LoadBalancer instance # LoadBalancer::__construct again calls ObjectCache::getMainWANInstance(); This is as a result of https://gerrit.wikimedia.org/r/#/c/300493/ which fixed T24923 This also results in any attempt to load any pages failing. git bisect shows that the above patch caused the issue.