Re: Logical Replication speed-up initial data

Hi Vijaykumar,

Thanks for the details.
In this method you are saying the pg_basebackup will make the initial load
faster ?
We intend to bring only a few tables. Using pg_basebackup will clone an
entire instance.

Thanks,
Nikhil

On Thu, Aug 5, 2021 at 7:57 PM Vijaykumar Jain <
vijaykumarjain(dot)github(at)gmail(dot)com> wrote:

> On Thu, 5 Aug 2021 at 10:27, Nikhil Shetty <nikhil(dot)dba04(at)gmail(dot)com> wrote:
>
>> Hi,
>>
>> Thank you for the suggestion.
>>
>> We tried by dropping indexes and it worked faster compared to what we saw
>> earlier. We wanted to know if anybody has done any other changes that helps
>> speed-up initial data load without dropping indexes.
>>
>>
> PS: i have not tested this in production level loads, it was just some exp
> i did on my laptop.
>
> one option would be to use pglogical extension (this was shared by
> Dharmendra in one the previous mails, sharing the same),
> and then use pglogical_create_subscriber cli to create the initial copy
> via pgbasebackup and then carry on from there.
> I ran the test case similar to one below in my local env, and it seems to
> work fine. of course i do not have TB worth of load to test, but it looks
> promising,
> especially since they introduced it to the core.
> pglogical/010_pglogical_create_subscriber.pl at REL2_x_STABLE ·
> 2ndQuadrant/pglogical (github.com)
> <https://github.com/2ndQuadrant/pglogical/blob/REL2_x_STABLE/t/010_pglogical_create_subscriber.pl>
> Once you attain some reasonable sync state, you can drop the pglogical
> extension, and check if things continue fine.
> I have done something similar when upgrading from 9.6 to 11 using
> pglogical and then dropping the extension and it was smooth,
> maybe you need to try this out and share if things works fine.
> and
> The 1-2-3 for PostgreSQL Logical Replication Using an RDS Snapshot -
> Percona Database Performance Blog
> <https://www.percona.com/blog/postgresql-logical-replication-using-an-rds-snapshot/>
>
>