Merge RootCoord, DataCoord And QueryCoord into MixCoord
Make Session into one
issue : https://github.com/milvus-io/milvus/issues/37764
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Signed-off-by: Xianhui.Lin <xianhui.lin@zilliz.com>
issue: #38399
related PR: #39522
- Just implement exclusive broadcaster between broadcast message with
same resource key to keep same order in different wal.
- After simplify the broadcast model, original watch-based broadcast is
too complicated and redundant, remove it.
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Signed-off-by: chyezh <chyezh@outlook.com>