Re: Parallel Apply

On 11/20/25 14:10, wenhui qiu wrote:
> Hi 
>> 1) The way the patch determines dependencies seems to be the "writeset"
>> approach from other replication systems (e.g. MySQL does that). Maybe we
>> should stick to the same naming?
> 
>> OK, I did not research the design in MySQL in detail but will try to
> analyze it.
> I have some documents  for mysql parallel apply binlog event.But after
> MySQL 8.4, only the writeset mode is available. In scenarios with a
> primary key or unique key, the replica replay is not ordered, but the
> data is eventually consistent."
> https://dev.mysql.com/worklog/task/?id=9556 <https://dev.mysql.com/
> worklog/task/?id=9556>
> https://dev.mysql.com/blog-archive/improving-the-parallel-applier-with-
> writeset-based-dependency-tracking/ <https://dev.mysql.com/blog-archive/
> improving-the-parallel-applier-with-writeset-based-dependency-tracking/>
> https://medium.com/airtable-eng/optimizing-mysql-replication-lag-with-
> parallel-replication-and-writeset-based-dependency-tracking-1fc405cf023c
> <https://medium.com/airtable-eng/optimizing-mysql-replication-lag-with-
> parallel-replication-and-writeset-based-dependency-tracking-1fc405cf023c>
> 

FWIW there was a talk about MySQL replication at pgconf.dev 2024

  https://www.youtube.com/watch?v=eOfUqh5PltM

discussing some of this stuff. I'm not saying we should copy all of
this, but it seems like a good source of inspiration what (not) to do.


regards

-- 
Tomas Vondra