Re: Index contains unexpected zero page at block

Victor Blomqvist <vb(at)viblo(dot)se> writes:
>> From time to time I get this and similar errors in my Postgres log file:
> < 2015-12-17 07:45:05.976 CST >ERROR: index
> "user_pictures_picture_dhash_idx" contains unexpected zero page at block
> 123780

Hm, can't tell for sure from the error message text, but the index name
suggests that this is a hash index?

> The server is a read slave, set up with streaming replication. We run
> PostgreSQL 9.3.5.

Hash indexes are not WAL-logged, which means their contents do not
propagate to slave servers, which basically means you cannot use them
in replication setups.

> Will it be fixed with a newer version of Postgres?

Adding WAL-logging to hash indexes has been on the to-do list for a long
time; but it's never gotten done, in part because there has never been
any clear evidence that hash indexes are better than btree indexes for
any real-world purpose. I'm curious why you chose this index type in
the first place.

regards, tom lane