issue #42492
- streamingcoord start before old rootcoord.
- streaming balancer will check the node session synchronously to avoid
redundant operation when cluster startup.
- ddl operation will check if streaming enabled, if the streaming is not
enabled, it will use msgstream.
- msgstream will initialize if streaming is not enabled, and stop when
streaming is enabled.
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #40532
- start timeticksync at rootcoord if the streaming service is not
available
- stop timeticksync if the streaming service is available
- open a read-only wal if some nodes in cluster is not upgrading to 2.6
- allow to open read-write wal after all nodes in cluster is upgrading
to 2.6
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Signed-off-by: chyezh <chyezh@outlook.com>
issue: #38399
- Embed the query node into streaming node to make delegator available
at streaming node.
- The embedded query node has a special server label
`QUERYNODE_STREAMING-EMBEDDED`.
- Change the balance strategy to make the channel assigned to streaming
node as much as possible.
Signed-off-by: chyezh <chyezh@outlook.com>