Some dropped layers serve as tombstones for earlier layers and thus cannot be garbage collected.
Add new fields to GcResult for layers that are preserved as tombstones
anyhow uses the alternate formatting style ("{:#}") to display all of
the causes of an error instead of the outermost context.
Without this, there's less information available to figure out what's
going on. It's probably too much to display in the compute node logs
though, so it's better to leave that formatting as-is.
In this test safekeepers are restarted one by one, while bank transactions
are executed and validated in the background. Bank transactions consist of
balance transfers and log writes. In the end balance sum should remain the
same and there should be progress from every client, when 2 of 3 safekeeper
nodes are up.
It's not interesting for most tests, and clutters the output. If there
are individual tests where it is worthwhole, let's add pg_controldata calls
to those tests, but I don't think it's needed for now.
If the 'latest' flag in the client request is true, the client wants the
latest page version regardless of the LSN in the request. The LSN is just
a hint in that case, indicating that the page hasn't been modified since
since that LSN. The LSN can be very old, so it's possible that the page
server has already garbage collected away the layer at that LSN. We tried
to fetch the old layer and errored out if that happened. To fix, always
fetch the data as of last-record-LSN, if 'latest' is set in the client
request. We now only use the LSN to wait if the requested LSN hasn't been
received and processed yet.
Fixes https://github.com/zenithdb/zenith/issues/567
- Use different message formats for different kinds of response messages.
- Add an Error message, for passing errors from page server to Postgres.
Previously, we would respond to 'exists' request with 'false', and
to 'nblocks' request with 0, if an error happened. Fix those to return
an error message to the client. GetPage requests had a mechanism to
return an error, but it was just a flag with no error message.
- Add a flag to requests, to indicate that we actually want the latest
page version on the timeline, and the LSN is just a hint that we know
that there haven't been any modifications since that LSN. The flag isn't
used for anything yet, but I'm planning to use it to fix
https://github.com/zenithdb/zenith/issues/567
Most of the previous usages of get_repository_for_tenant were followed
by immediately getting a timeline in that repository, without keeping it
around for longer.
The new `get_timeline_for_tenant` function implements that same
behavior, but in one line.
- Change hardcoded OLDEST_INMEM_DISTANCE value to pageserver config option checkpoint_distance.
- Get rid of 'force' flag in checkpoint_internal(). Use checkpoint_distance=0 instead.
Support is done via pytest-xdist plugin.
To use the feature add -n<concurrency> to pytest invocation
e.g. pytest -n8 to run 8 tests in parallel.
Changes in code are mostly about ports assigning. Previously port for
pageserver was hardcoded without the ability to override through zenith
cli and ports for started compute nodes were calculated twice, in zenith
cli and in test code. Now zenith cli supports port arguments for
pageserver and compute nodes to be passed explicitly.
Tests are modified in such a way that each worker gets a non overlapping
port range which can be configured and now contains 100 ports. These
ports are distributed to test services (pageserver, wal acceptors,
compute nodes) so they can work independently.
Data written to frozen layers is lost. It will not appear in on-disk
structures or in successor InMemoryLayers. Here we detect this race, and
fail. I think this race is rare, but this should make it easier to track
down when it happens.
Implement the changes suggested in a comment, create
`get_layer_for_read_locked` so that `get_layer_for_write` doesn't have
to drop the LayerMap lock when searching for the predecessor.
This contains a lowest common denominator of pageserver and safekeeper log
initialisation routines. It uses daemonize flag to decide where to
stream log messages. In case daemonize is true log messages are
forwarded to file. Otherwise streaming to stdout is used. Usage of
stdout for log output is the default in docker side of things, so make
it easier to browse our logs via builtin docker commands.
This job will be responsible for triggering remote CI pipeline in
zenithdb/console repository. That way, we'll always know when
a PR to zenithdb/zenith breaks the cloud console app.
Otherwise restart of safekeeper before the first segment is filled makes it
report 0 as flushed LSN. To this end, tweak find_end_of_wal_segment to allow
starting from given LSN, not only from the start of the segment. While here,
make it less panicky.
