I'm trying to do a migration from the internal HSQLDB database to a Sybase database. Our TeamCity instance has been running for almost a year now and so the HSQLDB has grown to 1.6G.
Unfortunately I keep hitting out of memory errors while it's trying to do the initial backup. I've tried twice now: once with 1G of heap and the second time with 2G of heap and they both fail while trying to export the downloaded_artifacts table (8.7 million rows). It's also really slow; the second migration attempt failed after 12 hours.
Does anybody have any experience doing a migration with a DB of this size? And does anybody know why the downloaded_artifacts table would be so big? That seems like a crazy number of rows to me. I'm thinking that it might be worth connecting to the HSQLDB and deleting some of these rows to help speed up the migration, but I'm not sure what the consequence of this would be.
Any help very much appreciated!