Re: [Tarantool-patches] [PATCH v2 01/10] applier: store instance_id in struct applier

[Serge Petrenko <sergepetrenko@tarantool.org>]

04.09.2020 01:51, Vladislav Shpilevoy пишет:
> Applier is going to need its numeric ID in order to tell the
> future Raft module who is a sender of a Raft message. An
> alternative would be to add sender ID to each Raft message, but
> this looks like a crutch. Moreover, applier still needs to know
> its numeric ID in order to notify Raft about heartbeats from the
> peer node.
>
> Needed for #1146

Hi! Thanks for the patch!

> ---
>   src/box/applier.cc | 19 +++++++++++++++++++
>   src/box/applier.h  |  2 ++
>   2 files changed, 21 insertions(+)
>
> diff --git a/src/box/applier.cc b/src/box/applier.cc
> index c1d07ca54..699b5a683 100644
> --- a/src/box/applier.cc
> +++ b/src/box/applier.cc
> @@ -67,6 +67,23 @@ applier_set_state(struct applier *applier, enum applier_state state)
>   	trigger_run_xc(&applier->on_state, applier);
>   }
>   
> +static inline void
> +applier_assign_instance_id(struct applier *applier)
Maybe call it `applier_set_id`? This way it's shorter and resembles 
`replica_set_id`.
> +{
> +	/*
> +	 * After final join, the applier already received latest
> +	 * records from _cluster, including the record about
> +	 * source instance. It can be absent in case the source is
> +	 * an anonymous replica.
> +	 */
> +	assert(applier->state == APPLIER_JOINED);
> +	struct replica *replica = replica_by_uuid(&applier->uuid);
> +	if (replica != NULL)
> +		applier->instance_id = replica->id;
> +	else
> +		assert(applier->instance_id == 0);
> +}
> +
>   /**
>    * Write a nice error message to log file on SocketError or ClientError
>    * in applier_f().
> @@ -603,6 +620,7 @@ applier_join(struct applier *applier)
>   	say_info("final data received");
>   
>   	applier_set_state(applier, APPLIER_JOINED);
> +	applier_assign_instance_id(applier);
>   	applier_set_state(applier, APPLIER_READY);
>   }
>   
> @@ -1207,6 +1225,7 @@ applier_subscribe(struct applier *applier)
>   		    instance_id != REPLICA_ID_NIL) {
>   			say_info("final data received");
>   			applier_set_state(applier, APPLIER_JOINED);
> +			applier_assign_instance_id(applier);
>   			applier_set_state(applier, APPLIER_READY);
>   			applier_set_state(applier, APPLIER_FOLLOW);
>   		}
> diff --git a/src/box/applier.h b/src/box/applier.h
> index 6e979a806..15ca1fcfd 100644
> --- a/src/box/applier.h
> +++ b/src/box/applier.h
> @@ -95,6 +95,8 @@ struct applier {
>   	ev_tstamp lag;
>   	/** The last box_error_code() logged to avoid log flooding */
>   	uint32_t last_logged_errcode;
> +	/** Remote instance ID. */
> +	uint32_t instance_id;
>   	/** Remote instance UUID */
>   	struct tt_uuid uuid;
>   	/** Remote URI (string) */

-- 
Serge Petrenko