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Ensure that any scheduled jobs on the deployment Advanced Options instance are disabled.
Avoid conducting the deployment process during business hours to prevent user interference.
Maintain a stable and fast internet connection throughout the deployment.
Monitor the firewall for potential performance limitations that could impede the deployment process.
Verify sufficient JVM resources and ensure adequate resource allocation, particularly JVM heap space. You can refer to the Jira Sizing guide: https://confluence.atlassian.com/jirakb/jira-server-sizing-guide-975033809.html and https://confluence.atlassian.com/enterprise/data-center-performance-946040735.html.
Install the most recent version of the Configuration Manager for the Advanced Options app on both the source and target instances to access the latest features and bug fixes.
When deploying a project with issues, avoid including attachment files in the snapshot to prevent unnecessary snapshot size increases. Instead, copy the attachments for the exported projects and move them to the target system. For more information, refer to the link: Move Attachments.
Disable re-indexing in the advanced settings by default to prevent a non-locking reindex after importing the issues. If you disable it, the deployment will not start a reindex, and you can start one yourself after the deployment. However, you may also start a locking reindex after deployment, which should be considerably faster. For more information, refer to the link: Advanced Options.
Allocate double the recommended amount for the heap. Typically, 8-16 GB of JVM heap is sufficient for large migrations and, in some cases, even 32 GB.
If you encounter performance issues with Jira Data Center during deployment, refer to the following articles for more details:
Jira Data Center performance problems during deployment
Data Center
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