Jira database migration from ORCL to Postgres

[Vhee Van]

Team,

We are planning to migrate the database from Oracle to Postgres on our Jira 10.x data center. 

We have done the migration successfully on a staging environment by mimicking PROD infrastructure, but the overall time taken to finish the import including end-to-end activities is around 60 hours (XML import and re-indexing alone took 50h). 

Since we are planning to do this migration on a weekend to minimize the impact to the end users, we want to reduce the import timing to 30 hours or less. 

We already checked with Atlassian support and they confirmed that our infra setup is above par and they do not have any other recommendations.

Our XML backup is 21 GB (without attachments) and app server has 48 vCPU, 128GB RAM, 64GB JVM heap, pool min/max size 500/5000 as per DBConfig.xml. Our Postgres DB server has 8vCPU, 32GB RAM and did not capture any errors during the entire import window. 

Can I ask for recommendations here to speed up the import process ? 

- Vhee

[Florian Bonniec]

Hi @Vhee Van 

Have you considered another migration solution like migrating the database from Oracle to PostgreSQL using db migration tools (ora2pg) ?

Usually XML backup restoration is the easiest but slowest solution.

Regards

[Vhee Van]

Hi @Florian Bonniec ,

Nope, I haven’t. Atlassian recommended to do the migration via XML restore only. So I haven’t considered DB level migration.

[Florian Bonniec]

I did not had to do Oracle to PostgreSQL but on huge instance and big downtime is not an option it's usually the solution I try to go with. 

It take more time to test because you will most likely have a lot of issues to fix and investigate. 

It's more complex but usually when properly tested in advanced, faster and reduce downtime.

Otherwise I do not see how to improve time with xml import.

Regards