Fix edge-case when a module client is unblocked (#8618)
Scenario: 1. A module client is blocked on keys with a timeout 2. Shortly before the timeout expires, the key is being populated and signaled as ready 3. Redis calls moduleTryServeClientBlockedOnKey (which replies to client) and then moduleUnblockClient 4. moduleUnblockClient doesn't really unblock the client, it writes to server.module_blocked_pipe and only marks the BC as unblocked. 5. beforeSleep kics in, by this time the client still exists and techincally timed-out. beforeSleep replies to the timeout client (double reply) and only then moduleHandleBlockedClients is called, reading from module_blocked_pipe and calling unblockClient The solution is similar to what was done in moduleTryServeClientBlockedOnKey: we should avoid re-processing an already-unblocked client
Please register or sign in to comment