[Tarantool-patches] [RFC] gc/xlog: delay xlog cleanup until relays are subscribed

[Vladislav Shpilevoy]

On 18.03.2021 08:51, Konstantin Osipov via Tarantool-patches wrote:
> * Cyrill Gorcunov <gorcunov at gmail.com> [21/03/18 10:42]:
>> Good point, thanks! Kostya, lets clarify some moments:
>>
>> 1) We introduce "wal_keep_logs" option which defines
>>    a timeout to kick the cleanup fiber.
>> 2) If node is anonymous replica we simply ignore this
>>    option.
>> 3) If this option is set then we have a few subcases:
>>    a) The `_cluster` space is not empty thus thus once
>>       all replicas are subscribed _before_ the timeout
>>       expired we trigger the cleanup fiber since it is
>>       safe to process;
>>    b) If replicas are not connected and timeout is
>>       expired we kick the cleanup fiber;
> 
> I mean this.

Then it should have 'replication_' prefix, not 'wal_'. Because
it is ignored if replicas connect before the timeout expires.