In the cleanup commit a840949ea0
a regression was introduced that caused backward incompatible changes
in the gossiper application state name strings.
In the e486e0f759 the value
`application_state::CDC_STREAMS_TIMESTAMP` was changed to
`application_state::CDC_GENERATION_ID`, but the name string
"CDC_STREAMS_TIMESTAMP" was kept for backward compatibility.
The cleanup commit a840949ea0 however
changed the name string to "CDC_GENERATION_ID" by ommission (not noticing
the difference) which caused backward incompatible change.
There is also another case found of "IGNOR_MSB_BITS" (that has a typo -
missing the "E" in "IGNORE") to "IGNORE_MSB_BITS", which also needs to
be reverted back to keep the backward compatibility.
Fixes: scylladb/scylladb#21811Closesscylladb/scylladb#21813
Implemented the group0 state_id handler (based on the gossip) that will
broadcast the group0 state id of each node.
This will be used to set the tombstone GC time for the group0 tables.
since we've switched almost all callers of the operator<< to {fmt},
let's drop the unused operator<<:s.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
this header was previously brought in by seastar's sstring.hh. but
since sstring.hh does not include <fmt/ostream.h> anymore,
`gms/application_state.cc` does not have access to this header.
also, `gms/application_state.cc` should `#include` the used header
by itself.
so, in this change, let's include <fmt/ostream.h> in `gms/application_state.cc`.
this change addresses the FTBFS with the latest seastar.
the same applies to other places changed in this commit.
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#18193
before this change, we rely on the default-generated fmt::formatter
created from operator<<, but fmt v10 dropped the default-generated
formatter.
in this change, we define formatters for `gms::application_state`,
but its operator<< is preserved, as it is still used by the generic
homebrew formatter for `std::unordered_map<>`.
Refs #13245
Signed-off-by: Kefu Chai <kefu.chai@scylladb.com>
Closesscylladb/scylladb#17096
It is equal to (if present) HOST_ID and no longer used for anything.
The application state was only gossiped if `experimental-features`
contained `raft`, so we can free this slot.
Similarly, `raft_server_id`s were only persisted in `system.peers` if
the `SUPPORTS_RAFT` cluster feature was enabled, which happened only
when `experimental-features` contained `raft`. The `raft_server_id`
field in the schema was also introduced recently in `master` and didn't
get to be in a release yet. Given either of these reasons, we can remove
this field safely.
We plan to use gossip data to educate Raft RPC about IP addresses
of raft peers. Add raft server ids to application state, so
that when we get a notification about a gossip peer we can
identify which raft server id this notification is for,
specifically, we can find what IP address stands for this server
id, and, whenever the IP address changes, we can update Raft
address map with the new address.
On the same token, at boot time, we now have to start Gossip
before Raft, since Raft won't be able to send any messages
without gossip data about IP addresses.
After fcb8d040 ("treewide: use Software Package Data Exchange
(SPDX) license identifiers"), many dual-licensed files were
left with empty comments on top. Remove them to avoid visual
noise.
Closes#10562
Instead of lengthy blurbs, switch to single-line, machine-readable
standardized (https://spdx.dev) license identifiers. The Linux kernel
switched long ago, so there is strong precedent.
Three cases are handled: AGPL-only, Apache-only, and dual licensed.
For the latter case, I chose (AGPL-3.0-or-later and Apache-2.0),
reasoning that our changes are extensive enough to apply our license.
The changes we applied mechanically with a script, except to
licenses/README.md.
Closes#9937
Each CDC generation always has a timestamp, but the fact that the
timestamp identifies the generation is an implementation detail.
We abstract away from this detail by using a more generic naming scheme:
a generation "identifier" (whatever that is - a timestamp or something
else).
It's possible that a CDC generation will be identified by more than a
timestamp in the (near) future.
The actual string gossiped by nodes in their application state is left
as "CDC_STREAMS_TIMESTAMP" for backward compatibility.
Some stale comments have been updated.
Snitch name needs to be exchanged within cluster once, on shadow
round, so joining nodes cannot use wrong snitch. The snitch names
are compared on bootstrap and on normal node start.
If the cluster already used mixed snitches, the upgrade to this
version will fail. In this case customer needs to add a node with
correct snitch for every node with the wrong snitch, then put
down the nodes with the wrong snitch and only then do the upgrade.
Fixes#6832Closes#7739
We would like to share with other nodes
the value of ignore_msb_bits property used by the node.
This is needed because CDC will operate on
streams of changes. Each shard on each node
will have its own stream that will be identified
by a stream_id. Stream_id will be selected in
such a way that using stream_id as partition key
will locate partition identified by stream_id on
a node and shard that the stream belongs to.
To be able to generate such stream_id we need
to know ignore_msb_bits property value for each node.
IMPORTANT NOTE: At this point CDC does not support
topology changes. It will work only on a stable cluster.
Support for topology modifications will be added in
later steps.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
We would like to share with other nodes
the number of shards available at the node.
This is needed because CDC will operate on
streams of changes. Each shard on each node
will have its own stream that will be identified
by a stream_id. Stream_id will be selected in
such a way that using stream_id as partition key
will locate partition identified by stream_id on
a node and shard that the stream belongs to.
To be able to generate such stream_id we need
to know how many shards are on each node.
IMPORTANT NOTE: At this point CDC does not support
topology changes. It will work only on a stable cluster.
Support for topology modifications will be added in
later steps.
Signed-off-by: Piotr Jastrzebski <piotr@scylladb.com>
This lays the groundwork for brokering a node's view update
backlog across the whole cluster. This is needed for when a
coordinator does not contact a given replica for a long time, and uses
a backlog view that is outdated and causes requests to be
unnecessarily delayed.
Signed-off-by: Duarte Nunes <duarte@scylladb.com>
When a node start it does not have any information about cache temperature
of other nodes in the cluster and it is hard (if not impossible) to make
right guess. During cluster startup all nodes have cold caches, so there
is no point to redirect reads to other nodes even though local cache it
cold, but if only that node restarted than other nodes have populated
cache and reads should be redirected.
The node will get up-to-date information about other nodes caches,
but only after receiving first reply, until then it does not have the
information to make right decisions which may cause unwanted spikes
immediately after restart. Having cache temperature in gossiper helps
to solve the problem.
- introcduced "seastarx.hh" header, which does a "using namespace seastar";
- 'net' namespace conflicts with seastar::net, renamed to 'netw'.
- 'transport' namespace conflicts with seastar::transport, renamed to
cql_transport.
- "logger" global variables now conflict with logger global type, renamed
to xlogger.
- other minor changes
