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Make RedisBagOStuff support tag name hashing
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Description

For ReplicatedBagOStuff to be useful (for sessions), the cache sub-objects need to use the same hashing scheme on both DCs. This is easy for the "master" sub-object but the "slave" sub-object requires either:
a) A local twemproxy instance being pointed to. twemproxy supports redis and tag name hashing
b) A small change to getConnection() in RedisBagOStuff such as allowing a (tag => server) map instead of just a server list in the configuration. Hashing would use the tag and pick the corresponding server.

In any case, the tags would be the eqiad hostnames to avoid re-hashing disruption.

Event Timeline

aaron created this task.Apr 5 2015, 7:05 PM
aaron claimed this task.
aaron raised the priority of this task from to Normal.
aaron updated the task description. (Show Details)
aaron added projects: Epic, MediaWiki-Core-Team.
aaron added subscribers: Gilles, GWicke, mark and 7 others.
aaron removed a project: Epic.Apr 5 2015, 10:22 PM
aaron set Security to None.

Change 202329 had a related patch set uploaded (by Aaron Schulz):
–Make RedisBagOStuff support tag name hashing

https://gerrit.wikimedia.org/r/202329

Change 202329 merged by jenkins-bot:
Make RedisBagOStuff support tag name hashing

https://gerrit.wikimedia.org/r/202329

aaron closed this task as Resolved.Apr 8 2015, 10:55 PM