How long could a big Confluence instance import take and how do I know if it's stuck?

[Shirley He]

Hello,

I just wanted to get a good gauge of how long a 56GB Confluence site restoration would take. I looked around and found that sometimes even a 2GB project could take hours and hours and still not be done, due to some sort of bug. I need to know what to look out for if something like this happens.

Regards,

Shirley

[Tobias Anstett _K15t_ · Accepted solution]

Hi @Shirley He,

Depending on the data in your site backup it will perform differently. E.g. if it contains a lot of attachments which are streamed to your disk or if everything is database content...

Nevertheless import depends heavily on your memory (Xmx) settings. Thus an import could take sooooooo long or fails/stops if it is to low.

For an export there is a rule of thumb from Atlassian "you need double as much RAM as the export result size" - I would also stick to this for an import to get it working and performing in a reasonable time.

Best, Tobias

[GMK]

Hi Shirley and Tobias,

Just to clarify: JVM memory size (Xms and xmx values) shouldn't affect restore time however it is true that insufficient Xmx value will lead to the crash and as a result unsuccessful restore (as xml backup restore is memory-consuming action).

But in general we don't recommend using XML backups including attachments for larger instances - try generating xml backup excluding attachments and then copy attachments directory separately to the new attachments path.

Another option is to use complete database dump and also separately copy attachments directories to a new location.

For more details see https://confluence.atlassian.com/doc/migrating-confluence-between-servers-184150.html and previously attached https://confluence.atlassian.com/doc/site-backup-and-restore-163578.html

Regards,

Greg

[Tobias Anstett _K15t_]

Thanks for adding this level of detail :)

[edwin · Accepted solution]

Hi @Shirley He,

What to look out for is whether data is still being written either to the database or to the home directory. I'd also tail the Confluence logs to monitor any error messages.

There is also another restore option if you have a database backup and a home directory backup.

Restoring Data from other Backups