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+# SegmentGrowing
+Segmentgrowing has the following additional interfaces:
+1. `PreInsert(size) -> reseveredOffset`: serial interface, which reserves space for future insertion and returns the insertion `reseveredOffset`.
+
+2. `Insert(reseveredOffset, size, ...Data...)`: write `...Data...` into range `[reseveredOffset, reseveredOffset + size)`. this interface is allowed to be called concurrently.
+    
+    1. `...Data...` contains row_ids, timestamps two system attributes, and other columns
+    2. data column can be stored either row based or columne based.
+    3. `PreDelete & Delete(reseveredOffset, row_ids, timestamps)` is the delete interface similar to intert interface.
+
+Growing segment stores data in the form of chunk. The number of rows in each chunk is restricted by configs,
+
+Rows per segment is controlled by parameters `size_per_Chunk ` control
+
+When insert, first allocate enough space to ensure  `total_size <= num_chunk * size_per_chunk`, and then convert data in row format to column format.
+
+During search, each 'chunk' will be searched, and the search results will be saved as 'subquery result',  then merged.
+
+GrGowing Segment also implements small batch index for vectors. The parameters of small batch index are preset in 'segcoreconfig'
+
+When `metric type ` is specified in the schema, the default parameters will build index for each chunk to accelerate query