Обсуждение: pg_dump --binary-upgrade out of memory
=?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/
Hi,
-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?
a quick and dirty solution might be an additional temporary swap space like this https://en.euro-linux.com/blog/creating-a-swap-file-or-how-to-deal-with-a-temporary-memory-shortage/
best,
Anton
Hi,
-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?
a quick and dirty solution might be an additional temporary swap space like this https://en.euro-linux.com/blog/creating-a-swap-file-or-how-to-deal-with-a-temporary-memory-shortage/
best,
Anton