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wikibase_shared/<current_train_version>-wikidatawiki-hhvm:CacheAwarePropertyInfoStore memcached key not well distributed, causing excessive traffic
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SRE team noticed that a specific host (mc1023) is close to saturating the uplink network connection [1]. More investigation into the grafana graphs for the entire cluster [2] showed that this is a recurring pattern that seems to follow hosts around. Doing a memkeys on mc1023 we found out that the key


is doing >600Mbps of traffic. The fact the train version is coded in the key name supports the theory of the key name following the train and being hashed to a different server, explaining the fact the traffic seems to follow hosts around.

This will cause an outage soon, needs to be fixed