=?UTF-8?B?0JDQvdGC0L7QvSDQk9C70YPRiNCw0LrQvtCy?= <a.glushakov86@gmail.com> writes:
> I encountered the problem of not being able to upgrade my instance (14->15)
> via pg_upgrade.
> The utility crashed with an error in out of memory.
> After researching a bit I found that this happens at the moment of export
> schema with pg_dump.
> Then I tried to manually perform a dump schema with the parameter
> --binary-upgrade option and also got an out of memory.
> Digging a little deeper, I discovered quite a large number of blob objects
> in the database (pg_largeobject 10GB and pg_largeobject_metadata 1GB (31kk
> rows))
Yeah, dumping a database with a lot of blobs is a known pain point.
I have some patches in progress that intend to make that better [1],
but they're meant for v17 and I'm not sure if you could get them to
work in v15. In the meantime, trying to run pg_dump on a beefier
machine might be your best option.
regards, tom lane
[1] https://commitfest.postgresql.org/47/4713/