Fix channel checkpoint stuck (#26534)

See also: #23621
Signed-off-by: Nyangxuan <xuan.yang@zilliz.com>

internal/datanode/channel_meta.go

@@ -274,7 +274,8 @@ func (c *ChannelMeta) listSegmentIDsToSync(ts Timestamp) []UniqueID {
 
 	validSegs := make([]*Segment, 0)
 	for _, seg := range c.segments {
-		if seg.getType() == datapb.SegmentType_Flushed || seg.getType() == datapb.SegmentType_Compacted {
+		// flushed segments also need to update cp
+		if !seg.isValid() {
 			continue
 		}
 		validSegs = append(validSegs, seg)
@@ -701,6 +702,7 @@ func (c *ChannelMeta) mergeFlushedSegments(ctx context.Context, seg *Segment, pl
 		if !c.hasSegment(ID, true) || c.hasSegment(ID, false) {
 			inValidSegments = append(inValidSegments, ID)
 		}
+
 	}
 
 	if len(inValidSegments) > 0 {
@@ -717,6 +719,7 @@ func (c *ChannelMeta) mergeFlushedSegments(ctx context.Context, seg *Segment, pl
 		return errors.New("invalid context")
 	default:
 	}
+
 	for _, ID := range compactedFrom {
 		// the existent of the segments are already checked
 		s := c.segments[ID]
@@ -725,6 +728,11 @@ func (c *ChannelMeta) mergeFlushedSegments(ctx context.Context, seg *Segment, pl
 		// release bloom filter
 		s.currentStat = nil
 		s.historyStats = nil
+
+		// set correct lastSyncTs for 10-mins channelCP force sync.
+		if s.lastSyncTs < seg.lastSyncTs {
+			seg.lastSyncTs = s.lastSyncTs
+		}
 	}
 
 	// only store segments with numRows > 0