## Problem
We want to be able to test how our infrastructure reacts on segfaults in
Postgres (for example, we collect cores, and get some required
logs/metrics, etc)
## Summary of changes
- Add `trigger_segfauls` function to `neon_test_utils` to trigger a
segfault in Postgres
- Add `trigger_panic` function to `neon_test_utils` to trigger SIGABRT
(by using `elog(PANIC, ...))
- Fix cleanup logic in regression tests in endpoint crashed
This makes it much more convenient to use in the common case that you
want to flush all the WAL. (Passing pg_current_wal_insert_lsn() as the
argument doesn't work for the same reasons as explained in the
comments: we need to be back off to the beginning of a page if the
previous record ended at page boundary.)
I plan to use this to fix the issue that Arseny Sher called out at
https://github.com/neondatabase/neon/pull/7288#discussion_r1660063852
The test utils should only be used during tests. Users should not be
able to create this extension on their own.
Signed-off-by: Alex Chi Z <chi@neon.tech>
Instead of thinking in terms of 'latest' and 'lsn' of the request,
each request has two LSNs: the request LSN and 'not_modified_since'
LSN. The request is nominally made at the request LSN, that determines
what page version we want to see. But as a hint, we also include
'not_modified_since'. It tells the pageserver that the page has not
been modified since that LSN, which allows the pageserver to skip
waiting for newer WAL to arrive, and could allow more optimizations in
the future.
Refactor the internal functions to calculate the request LSN to
calculate both LSNs.
Sending two LSNs to the pageserver requires using the new protocol
version 2. The previous commit added the server support for it, but we
still default to the old protocol for compatibility with old
pageservers. The 'neon.protocol_version' GUC can be used to use the
new protocol.
The new protocol addresses one cause of issue #6211, although you can
still get the same error if you have a standby that is lagging behind
so that the page version it needs is genuinely GC'd away.
## Problem
Building on #5875 to add handy test functions for autoscaling.
Resolves#5609
## Summary of changes
This PR makes the following changes to #5875:
- Enable `neon_test_utils` extension in the compute node docker image,
so we could use it in the e2e tests (as discussed with @kelvich).
- Removed test functions related to disk as we don't use them for
autoscaling.
- Fix the warning with printf-ing unsigned long variables.
---------
Co-authored-by: Heikki Linnakangas <heikki@neon.tech>
* Extract neon and neon_test_utils from postgres repo
* Remove neon from vendored postgres repo, and fix build_and_test.yml
* Move EmitWarningsOnPlaceholders to end of _PG_init in neon.c (from libpagestore.c)
* Fix Makefile location comments
* remove Makefile EXTRA_INSTALL flag
* Update Dockerfile.compute-node to build and include the neon extension