When in tablets_mode_for_new_keyspaces=enforced mode, Alternator is
supposed to fail when CreateTable asks explicitly for vnodes. Before
this patch, this error was an ugly "Internal Server Error" (an
exception thrown from deep inside the implementation), this patch
checks for this case in the right place, to generate a proper
ValidationException with a proper error message.
We also enable the test test_tablets_tag_vs_config which should have
caught this error, but didn't because it was marked xfail because
tablets_mode_for_new_keyspaces had not been live-updatable. Now that
it is, we can enable the test. I also improved the test to be slightly
faster (no need to change the configuration so many times) and also
check the ordinary case - where the schema doesn't choose neither
vnodes nor tablets explicitly and we should just use the default.
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
The test should pass without the fix for scylladb/scylladb#26615,
because the `executor::updata_table()` uses
`service::prepare_new_view_announcement()`, which creates view building
tasks for the view.
But it's better to add this test.
update all the references about the issue of tablets support for
alternator streams to issue #23838 instead of #16317.
The issue #16317 is about support of CDC with tablets, but it is now
closed and it didn't address alternator streams. the remaining issues
about alternator streams should be addressed as part of #23838, so fix
the references in order for them not to be missed.
Support for TTL-based data removal when using tablets.
The essence of this commit is a separate code path for finding token
ranges owned by the current shard for the cases when tablets are used
and not vnodes. At the same time, the vnodes-case is not touched not to
cause any regressions.
The TTL-caused data removal is normally performed by the primary
replica (both when using vnodes and tablets). For the tablets case,
the already-existing method tablet_map::get_primary_replica(tablet_id)
is used to know if a shard execuring the TTL-related data removal is
the primary replica for each tablet.
A new method tablet_map::get_secondary_replica(tablet_id) has been
added. It is needed by the data invalidation procedure to remove data
when the primary replica node is down - the data is then removed by the
secondary replica node. The mechanism is the same as in the vnodes case.
Since alternator now supports TTL, the test
`test_ttl_enable_error_with_tablets` has been removed.
Also, tests in the test_ttl.py have been made to run twice, once with
vnodes and once with tablets. When run with tablets, the due to lack of
support for LWT with tablets (#18068), tests use
'system:write_isolation' of 'unsafe_rmw'. This approach allows early
regression testing with tablets and is meant only as a tentative
solution.
Fixesscylladb/scylladb#16567Closesscylladb/scylladb#23662
In commit c24bc3b we decided that creating a new table in Alternator
will by default use vnodes - not tablets - because of all the missing
features in our tablets implementation that are important for
Alternator, namely - LWT, CDC and Alternator TTL.
We never documented this, or the fact that we support a tag
`experimental:initial_tablets` which allows to override this decision
and create an Alternator table using tablets. We also never documented
what exactly doesn't work when Alternator uses tablet.
This patch adds the missing documentation in docs/alternator/new-apis.md
(which is a good place for describing the `experimental:initial_tablets`
tag). The patch also adds a new test file, test_tablets.py, which
includes tests for all the statements made in the document regarding
how `experimental:initial_tablets` works and what works or doesn't
work when tablets are enabled.
Two existing tests - for TTL and Streams non-support with tablets -
are moved to the new test file.
When the tablets feature will finally be completed, both the document
and the tests will need to be modified (some of the tests should be
outright deleted). But it seems this will not happen for at least
several months, and that is too long to wait without accurate
documentation.
Fixes#21629
Signed-off-by: Nadav Har'El <nyh@scylladb.com>
Closesscylladb/scylladb#22462
