Hi.
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))
I was able to reproduce the problem on a clean server by simply putting some random data in pg_largeobject_metadata
$insert into pg_largeobject_metadata (select i,16390 from generate_series(107659,34274365) as i);
$pg_dump --binary-upgrade --format=custom -d mydb -s -f tmp.dmp
and after 1-2 min get out of memory ( i tried on server with 4 and 8 gb RAM)
Perhaps this is a bug?
How can I perform an upgrade?
