See also #27675
Fix logic problem introduced by #29413, which is serializer tries to
merge statslog list while level segments do not have statslog. This
shall result returning error. `writeBufferBase` ignores this error but
it shall only ignore `ErrSegmentNotFound`.
This PR add logic checking segment level before execution of merging
statslog list. And add error type check for getSyncTask failure.
Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>
See also #27675
Since serialization segment buffer does not related to sync manager can
shall be done before submit into sync manager. So that the pk statistic
file could be more accurate and reduce complex logic inside sync
manager.
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Signed-off-by: Congqi Xia <congqi.xia@zilliz.com>