[tarantool-patches] Re: [PATCH v4 8/9] applier: apply transaction in parallel
Konstantin Osipov
kostja at tarantool.org
Thu Jun 20 11:06:27 MSK 2019
* Georgy Kirichenko <georgy at tarantool.org> [19/06/20 09:54]:
> applier_apply_tx(struct stailq *rows)
> {
> + struct xrow_header *first_row =
> + &stailq_first_entry(rows, struct applier_tx_row,
> + next)->row;
> + struct replica *replica = replica_by_id(first_row->replica_id);
> + struct latch *latch = (replica ? &replica->order_latch :
> + &replicaset.applier.order_latch);
> + latch_lock(latch);
Now that we have a sequencer shouldn't it handle the job of this
latch as well?
> + if (vclock_get(&replicaset.applier.net_vclock, first_row->replica_id) >=
> + first_row->lsn) {
> + /* Check there is a heathbeat message and wake a writers up. */
> + if (first_row->lsn == 0)
> + fiber_cond_broadcast(&replicaset.applier.commit_cond);
> + latch_unlock(latch);
> + return 0;
> + }
> +
> + /*
> + * A vclock of the last transaction wich was read
> + * from an applier connection.
> + */
> + struct vclock net_vclock;
> + /* Signaled on replicated transaction commit. */
I don't understand this comment, what is a replicated transaction
commit? Could you please rephrase? Why do you need this cond?
Please add more comments explaining how and why.
> + struct fiber_cond commit_cond;
> + /*
> + * Trigger to fire when replication stops in case
> + * of an error.
> + */
> + struct rlist on_replication_fail;
I would simply call it on_error on_failure. It's already clear it's related to the
applier work. Please explain how and why
this trigger is used in the comment.
> + /* Diag to populate an error acros all appliers. */
> + struct diag diag;
> } applier;
> /** Map of all known replica_id's to correspponding replica's. */
> struct replica **replica_by_id;
--
Konstantin Osipov, Moscow, Russia
More information about the Tarantool-patches
mailing list