Related to #44620
Related to unstable ut "internal/querycoordv2 TestServer/TestNodeUp"
Introduce SessionWatcher interface to fix race condition and goroutine
leak that caused unstable unit test TestServer/TestNodeUp.
Changes:
- Add SessionWatcher interface with EventChannel() and Stop() methods
- Refactor WatchServices() to return SessionWatcher instead of raw
channel
- Fix cleanup order in QueryCoordV2: stop watcher before session
- Update DataCoord, ConnectionManager to use SessionWatcher
- Add MockSessionWatcher for testing
Fixes race condition between session context cancellation and internal
loop exit. Eliminates goroutine leak by providing explicit lifecycle
management.
---------
Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>
issue: #34553
when rootcoord trigger graceful stop progress, it will block until all
rpc finished. for create collection request, rootcoord need to block
until datacoord finish to watch all channels, but datacoord need to call
`rootcoord.Alloc` during watch channel, and rootcoord doesn't respond to
new request anymore. which cause create collection stucks, and graceful
stop progress stucks.
This PR remove the func call `rootcoord.Alloc` to solve the logic dead
lock during graceful stop progress.
Signed-off-by: Wei Liu <wei.liu@zilliz.com>