The meaning of the parameter changes from defining whether the function
is called in testing environment to deciding whether a delay should be
added to a timestamp of a newly created CDC generation.
This is a preparation for improvement in the following patch that does
not always add delay to every node but only to non-first node.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Following patch enables CDC by default and this means CDC has to work
will all the clusters now.
There is a problematic case when existing cluster with no CDC support
is stopped, all the binaries are updated to newer version with
CDC enabled by default. In such case, nodes know that they are already
members of the cluster but they can't find any CDC generation so they
will try to create one. This creation may fail due to lack of QUORUM
for the write.
Before this patch such situation would lead to node failing to start.
After the change, the node will start but CDC generation will be
missing. This will mean CDC won't be able to work on such cluster before
nodetool checkAndRepairCdcStreams is run to fix the CDC generation.
We still fail to bootstrap if the creation of CDC generation fails.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
Fixes#7345Fixes#7346
Do a more efficient collection skip when doing paging, instead of
iterating the full sets.
Ensure some semblance of sanity in the parent-child relationship
between shards by ensuring token order sorting and finding the
apparent previous ID coverting the approximate range of new gen.
Fix endsequencenumber generation by looking at whether we are
last gen or not, instead of the (not filled in) 'expired' column.
Commit a6ad70d3da changed the format of
stream IDs: the lower 8 bytes were previously generated randomly, now
some of them have semantics. In particular, the least significant byte
contains a version (stream IDs might evolve with further releases).
This is a backward-incompatible change: the code won't properly handle
stream IDs with all lower 8 bytes generated randomly. To protect us from
subtle bugs, the code has an assertion that checks the stream ID's
version.
This means that if an experimental user used CDC before the change and
then upgraded, they might hit the assertion when a node attempts to
retrieve a CDC generation with old stream IDs from the CDC description
tables and then decode it.
In effect, the user won't even be able to start a node.
Similarly as with the case described in
d89b7a0548, the simplest fix is to rename
the tables. This fix must get merged in before CDC goes out of
experimental.
Now, if the user upgrades their cluster from a pre-rename version, the
node will simply complain that it can't obtain the CDC generation
instead of preventing the cluster from working. The user will be able to
use CDC after running checkAndRepairCDCStreams.
Since a new table is added to the system_distributed keyspace, the
cluster's schema has changed, so sstables and digests need to be
regenerated for schema_digest_test.
Fixes#6948
Changes the stream_id format from
<token:64>:<rand:64>
to
<token:64>:<rand:38><index:22><version:4>
The code will attempt to assert version match when
presented with a stored id (i.e. construct from bytes).
This means that ID:s created by previous (experimental)
versions will break.
Moves the ID encoding fully into the ID class, and makes
the code path private for the topology generation code
path.
Removes some superflous accessors but adds accessors for
token, version and index. (For alternator etc).
Commit 968177da04 has changed the schema
of cdc_topology_description and cdc_description tables in the
system_distributed keyspace.
Unfortunately this was a backwards-incompatible change: these tables
would always be created, irrespective of whether or not "experimental"
was enabled. They just wouldn't be populated with experimental=off.
If the user now tries to upgrade Scylla from a version before this change
to a version after this change, it will work as long as CDC is protected
b the experimental flag and the flag is off.
However, if we drop the flag, or if the user turns experimental on,
weird things will happen, such as nodes refusing to start because they
try to populate cdc_topology_description while assuming a different schema
for this table.
The simplest fix for this problem is to rename the tables. This fix must
get merged in before CDC goes out of experimental.
If the user upgrades his cluster from a pre-rename version, he will simply
have two garbage tables that he is free to delete after upgrading.
sstables and digests need to be regenerated for schema_digest_test since
this commit effectively adds new tables to the system_distributed keyspace.
This doesn't result in schema disagreement because the table is
announced to all nodes through the migration manager.
In new CDC Log format stream_id is represented by a single
blob column so it makes sense to store it in the same form
everywhere - including internal CDC tables.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
New CDC Log format stores stream ids as blobs.
It makes sense to keep them internally in the same form.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
CDC can get all it needs from a config and does not need
partitioner.
For base table specific operations CDC is using partitioner
from that table (obtained with schema::get_partitioner).
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
In future commits this will be used by nodes learning about other nodes
entering NORMAL status. The joining node proposes a new generation of streams,
whose timestamp is gossiped by the node.
This is a class that will be used for storing information
required to perform CDC operations, i.e. assignment of token ranges to
CDC streams.
It is serializable to bytes and will be stored
in such a form in a distributed table accessible
by all nodes.
