Re: Alter table set logged hanging after writing out all WAL

On Tue, Feb 06, 2018 at 12:50:56AM -0600, Jeremy Finzel wrote:
> The table I am setting to logged is 32GB with indexes.  I see it writing
> WAL files like crazy but after about an hour and a half, it has written out
> some 2500 WAL segments, then it just sits and continues to run as "active",
> but no more WAL files are being created.  There are no locks, and no other
> transactions in the system running.

Switching an unlogged table to be logged causes an entire image of the
table to be WAL-logged so as the operation is consistent in case of a
crash.

> Any ideas?  Is it still doing something that I need to wait for?

Do you have a backtrace with the process doing the ALTER TABLE hanging?
How is structured you table with its indexes?  It is a bit hard to guess
much without more information.
--
Michael