chore(query): row fetch will be fetched by distinct block batch (#17391)

* chore(query): row fetch will be fetched by distinct block batch

* chore(query): row fetch will be fetched by distinct block batch

* chore(query): row fetch will be fetched by distinct block batch

* increase permit

Author: sundy-li

Cargo.lock

@@ -12,8 +12,10 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
+use std::collections::HashSet;
 use std::sync::Arc;
 
+use databend_common_catalog::plan::split_row_id;
 use databend_common_catalog::plan::DataSourcePlan;
 use databend_common_catalog::plan::Projection;
 use databend_common_catalog::table_context::TableContext;
@@ -66,6 +68,7 @@ pub fn row_fetch_processor(
                     input,
                     output,
                     row_id_col_offset,
+                    max_threads,
                     NativeRowsFetcher::<true>::create(
                         fuse_table.clone(),
                         projection.clone(),
@@ -79,6 +82,7 @@ pub fn row_fetch_processor(
                     input,
                     output,
                     row_id_col_offset,
+                    max_threads,
                     NativeRowsFetcher::<false>::create(
                         fuse_table.clone(),
                         projection.clone(),
@@ -97,6 +101,7 @@ pub fn row_fetch_processor(
                         input,
                         output,
                         row_id_col_offset,
+                        max_threads,
                         ParquetRowsFetcher::<true>::create(
                             fuse_table.clone(),
                             projection.clone(),
@@ -111,6 +116,7 @@ pub fn row_fetch_processor(
                         input,
                         output,
                         row_id_col_offset,
+                        max_threads,
                         ParquetRowsFetcher::<false>::create(
                             fuse_table.clone(),
                             projection.clone(),
@@ -130,13 +136,17 @@ pub fn row_fetch_processor(
 pub trait RowsFetcher {
     async fn on_start(&mut self) -> Result<()>;
     async fn fetch(&mut self, row_ids: &[u64]) -> Result<DataBlock>;
+    fn clear_cache(&mut self);
 }
 
 pub struct TransformRowsFetcher<F: RowsFetcher> {
     row_id_col_offset: usize,
+    max_threads: usize,
     fetcher: F,
     need_wrap_nullable: bool,
     blocks: Vec<DataBlock>,
+    row_ids: Vec<u64>,
+    distinct_block_ids: HashSet<u64>,
 }
 
 #[async_trait::async_trait]
@@ -151,26 +161,7 @@ where F: RowsFetcher + Send + Sync + 'static
     }
 
     async fn transform(&mut self, data: DataBlock) -> Result<Option<DataBlock>> {
-        self.blocks.push(data);
-        Ok(None)
-    }
-
-    #[async_backtrace::framed]
-    async fn on_finish(&mut self, _output: bool) -> Result<Option<DataBlock>> {
-        if self.blocks.is_empty() {
-            return Ok(None);
-        }
-
-        let start_time = std::time::Instant::now();
-        let num_blocks = self.blocks.len();
-        let mut data = DataBlock::concat(&self.blocks)?;
-        self.blocks.clear();
-
         let num_rows = data.num_rows();
-        if num_rows == 0 {
-            return Ok(None);
-        }
-
         let entry = &data.columns()[self.row_id_col_offset];
         let value = entry
             .value
@@ -184,24 +175,43 @@ where F: RowsFetcher + Send + Sync + 'static
             value.column.into_number().unwrap().into_u_int64().unwrap()
         };
 
-        let fetched_block = self.fetcher.fetch(&row_id_column).await?;
+        // Process the row id column in block batch
+        // Ensure that the same block would be processed in the same batch and threads
+        let mut consumed_len = num_rows;
+        for (idx, row_id) in row_id_column.iter().enumerate() {
+            let (prefix, _) = split_row_id(*row_id);
 
-        for col in fetched_block.columns().iter() {
-            if self.need_wrap_nullable {
-                data.add_column(wrap_true_validity(col, num_rows));
-            } else {
-                data.add_column(col.clone());
+            // Which means we are full now, new prefix will be processed in next batch
+            if self.distinct_block_ids.len() >= self.max_threads * 2
+                && !self.distinct_block_ids.contains(&prefix)
+            {
+                consumed_len = idx;
+                break;
             }
+            self.distinct_block_ids.insert(prefix);
         }
 
-        log::info!(
-            "TransformRowsFetcher on_finish: num_rows: {}, input blocks: {} in {} milliseconds",
-            num_rows,
-            num_blocks,
-            start_time.elapsed().as_millis()
-        );
+        self.row_ids
+            .extend_from_slice(&row_id_column.as_slice()[0..consumed_len]);
+        self.blocks.push(data.slice(0..consumed_len));
 
-        Ok(Some(data))
+        if consumed_len < num_rows {
+            let block = self.flush().await;
+            for row_id in row_id_column.as_slice()[consumed_len..num_rows].iter() {
+                let (prefix, _) = split_row_id(*row_id);
+                self.distinct_block_ids.insert(prefix);
+                self.row_ids.push(*row_id);
+            }
+            self.blocks.push(data.slice(consumed_len..num_rows));
+            block
+        } else {
+            Ok(None)
+        }
+    }
+
+    #[async_backtrace::framed]
+    async fn on_finish(&mut self, _output: bool) -> Result<Option<DataBlock>> {
+        self.flush().await
     }
 }
 
@@ -212,16 +222,59 @@ where F: RowsFetcher + Send + Sync + 'static
         input: Arc<InputPort>,
         output: Arc<OutputPort>,
         row_id_col_offset: usize,
+        max_threads: usize,
         fetcher: F,
         need_wrap_nullable: bool,
     ) -> ProcessorPtr {
         ProcessorPtr::create(AsyncAccumulatingTransformer::create(input, output, Self {
             row_id_col_offset,
+            max_threads,
             fetcher,
             need_wrap_nullable,
             blocks: vec![],
+            row_ids: vec![],
+            distinct_block_ids: HashSet::new(),
         }))
     }
+
+    async fn flush(&mut self) -> Result<Option<DataBlock>> {
+        let blocks = std::mem::take(&mut self.blocks);
+        if blocks.is_empty() {
+            return Ok(None);
+        }
+
+        let start_time = std::time::Instant::now();
+        let num_blocks = blocks.len();
+        let mut data = DataBlock::concat(&blocks)?;
+        let num_rows = data.num_rows();
+        if num_rows == 0 {
+            return Ok(None);
+        }
+
+        let row_ids = std::mem::take(&mut self.row_ids);
+        self.distinct_block_ids.clear();
+        let fetched_block = self.fetcher.fetch(&row_ids).await?;
+        // Clear cache after fetch, the block will never be fetched in following batches
+        // We ensure it in transform method
+        self.fetcher.clear_cache();
+
+        for col in fetched_block.columns().iter() {
+            if self.need_wrap_nullable {
+                data.add_column(wrap_true_validity(col, num_rows));
+            } else {
+                data.add_column(col.clone());
+            }
+        }
+
+        log::info!(
+            "TransformRowsFetcher flush: num_rows: {}, input blocks: {} in {} milliseconds",
+            num_rows,
+            num_blocks,
+            start_time.elapsed().as_millis()
+        );
+
+        Ok(Some(data))
+    }
 }
 
 fn wrap_true_validity(column: &BlockEntry, num_rows: usize) -> BlockEntry {

src/query/storages/fuse/src/operations/read/fuse_rows_fetcher.rs

@@ -64,6 +64,10 @@ impl<const BLOCKING_IO: bool> RowsFetcher for NativeRowsFetcher<BLOCKING_IO> {
         Ok(())
     }
 
+    fn clear_cache(&mut self) {
+        self.part_map.clear();
+    }
+
     #[async_backtrace::framed]
     async fn fetch(&mut self, row_ids: &[u64]) -> Result<DataBlock> {
         self.prepare_part_map(row_ids).await?;

src/query/storages/fuse/src/operations/read/native_rows_fetcher.rs

@@ -66,6 +66,10 @@ impl<const BLOCKING_IO: bool> RowsFetcher for ParquetRowsFetcher<BLOCKING_IO> {
         Ok(())
     }
 
+    fn clear_cache(&mut self) {
+        self.part_map.clear();
+    }
+
     #[async_backtrace::framed]
     async fn fetch(&mut self, row_ids: &[u64]) -> Result<DataBlock> {
         self.prepare_part_map(row_ids).await?;