Heikki Linnakangas eb1bdcc6cf If an FSM or VM page cannot be reconstructed, fill it with zeros. ...

If we cannot reconstruct an FSM or VM page, while creating image
layers, fill it with zeros instead. That should always be safe, for
the FSM and VM, in the sense that you won't lose actual user data. It
will get cleaned up by VACUUM later.

We had a bug with FSM/VM truncation, where we truncated the FSM and VM
at WAL replay to a smaller size than PostgreSQL originally did. We
thought was harmless, as the FSM and VM are not critical for
correctness and can be zeroed out or truncated without affecting user
data. However, it lead to a situation where PostgreSQL created
incremental WAL records for pages that we had already truncated away
in the pageserver, and when we tried to replay those WAL records, that
failed. That lead to a permanent error in image layer creation, and
prevented it from ever finishing. See
https://github.com/neondatabase/neon/issues/2601. With this patch,
those pages will be filled with zeros in the image layer, which allows
the image layer creation to finish.

2022-10-20 17:27:01 +03:00

..

benches

Add micro-benchmark for layer map search function

2022-10-18 15:00:10 +03:00

src

If an FSM or VM page cannot be reconstructed, fill it with zeros.

2022-10-20 17:27:01 +03:00

Cargo.toml

Use an optimized version of amplify_num.

2022-10-18 15:00:10 +03:00