Accelerate flush in flushAll (#26769)

Signed-off-by: bigsheeper <yihao.dai@zilliz.com>

internal/proxy/impl.go

@@ -3172,14 +3172,11 @@ func (node *Proxy) FlushAll(ctx context.Context, _ *milvuspb.FlushAllRequest) (*
 
 	hasError := func(status *commonpb.Status, err error) bool {
 		if err != nil {
-			resp.Status = &commonpb.Status{
-				ErrorCode: commonpb.ErrorCode_UnexpectedError,
-				Reason:    err.Error(),
-			}
+			resp.Status = merr.Status(err)
 			log.Warn("FlushAll failed", zap.String("err", err.Error()))
 			return true
 		}
-		if status.ErrorCode != commonpb.ErrorCode_Success {
+		if status != nil && status.ErrorCode != commonpb.ErrorCode_Success {
 			log.Warn("FlushAll failed", zap.String("err", status.GetReason()))
 			resp.Status = status
 			return true
@@ -3204,12 +3201,26 @@ func (node *Proxy) FlushAll(ctx context.Context, _ *milvuspb.FlushAllRequest) (*
 			return resp, nil
 		}
 
-		flushRsp, err := node.Flush(ctx, &milvuspb.FlushRequest{
-			Base:            commonpbutil.NewMsgBase(commonpbutil.WithMsgType(commonpb.MsgType_Flush)),
-			DbName:          dbName,
-			CollectionNames: showColRsp.GetCollectionNames(),
-		})
-		if hasError(flushRsp.GetStatus(), err) {
+		group, ctx := errgroup.WithContext(ctx)
+		for _, collection := range showColRsp.GetCollectionNames() {
+			collection := collection
+			group.Go(func() error {
+				flushRsp, err := node.Flush(ctx, &milvuspb.FlushRequest{
+					Base:            commonpbutil.NewMsgBase(commonpbutil.WithMsgType(commonpb.MsgType_Flush)),
+					DbName:          dbName,
+					CollectionNames: []string{collection},
+				})
+				if err != nil {
+					return err
+				}
+				if flushRsp.GetStatus().GetErrorCode() != commonpb.ErrorCode_Success {
+					return merr.Error(flushRsp.GetStatus())
+				}
+				return nil
+			})
+		}
+		err = group.Wait()
+		if hasError(nil, err) {
 			return resp, nil
 		}
 	}