fix: obsolete wal entires while opening a migrated region

src/datanode/src/heartbeat/handler/downgrade_region.rs

@@ -74,6 +74,10 @@ impl HandlerContext {
 
             // Ignores flush request
             if !writable {
+                warn!(
+                    "Region: {region_id} is not writable, flush_timeout: {:?}",
+                    flush_timeout
+                );
                 return self.downgrade_to_follower_gracefully(region_id).await;
             }
 

src/meta-srv/src/procedure/region_migration/downgrade_leader_region.rs

@@ -165,6 +165,7 @@ impl DowngradeLeaderRegion {
         match receiver.await? {
             Ok(msg) => {
                 let reply = HeartbeatMailbox::json_reply(&msg)?;
+                info!("Downgrade region reply: {:?}", reply);
                 let InstructionReply::DowngradeRegion(DowngradeRegionReply {
                     last_entry_id,
                     exists,

src/meta-srv/src/procedure/region_migration/open_candidate_region.rs

@@ -21,6 +21,7 @@ use common_meta::instruction::{Instruction, InstructionReply, OpenRegion, Simple
 use common_meta::key::datanode_table::RegionInfo;
 use common_meta::RegionIdent;
 use common_procedure::Status;
+use common_telemetry::info;
 use serde::{Deserialize, Serialize};
 use snafu::{OptionExt, ResultExt};
 
@@ -144,6 +145,7 @@ impl OpenCandidateRegion {
         match receiver.await? {
             Ok(msg) => {
                 let reply = HeartbeatMailbox::json_reply(&msg)?;
+                info!("Received open region reply: {:?}", reply);
                 let InstructionReply::OpenRegion(SimpleReply { result, error }) = reply else {
                     return error::UnexpectedInstructionReplySnafu {
                         mailbox_message: msg.to_string(),

src/mito2/src/worker/handle_catchup.rs

@@ -49,7 +49,8 @@ impl<S: LogStore> RegionWorkerLoop<S> {
         // Utilizes the short circuit evaluation.
         let region = if !is_mutable_empty || region.manifest_ctx.has_update().await? {
             let manifest_version = region.manifest_ctx.manifest_version().await;
-            info!("Reopening the region: {region_id}, empty mutable: {is_mutable_empty}, manifest version: {manifest_version}");
+            let flushed_entry_id = region.version_control.current().last_entry_id;
+            info!("Reopening the region: {region_id}, empty mutable: {is_mutable_empty}, manifest version: {manifest_version}, flushed entry id: {flushed_entry_id}");
             let reopened_region = Arc::new(
                 RegionOpener::new(
                     region_id,
@@ -111,6 +112,9 @@ impl<S: LogStore> RegionWorkerLoop<S> {
             }
         } else {
             warn!("Skips to replay memtable for region: {}", region.region_id);
+            let flushed_entry_id = region.version_control.current().last_entry_id;
+            let on_region_opened = self.wal.on_region_opened();
+            on_region_opened(region_id, flushed_entry_id, &region.provider).await?;
         }
 
         if request.set_writable {

tests-fuzz/targets/migration/fuzz_migrate_mito_regions.rs

@@ -80,10 +80,10 @@ impl Arbitrary<'_> for FuzzInput {
         let rows = rng.gen_range(128..1024);
         let inserts = rng.gen_range(2..8);
         Ok(FuzzInput {
-            partitions,
+            seed,
             columns,
+            partitions,
             rows,
-            seed,
             inserts,
         })
     }
@@ -133,22 +133,15 @@ struct Migration {
     region_id: RegionId,
 }
 
-async fn execute_region_migration(ctx: FuzzContext, input: FuzzInput) -> Result<()> {
-    info!("input: {:?}", input);
-    let mut rng = ChaChaRng::seed_from_u64(input.seed);
-
-    let create_expr = generate_create_expr(input, &mut rng)?;
-    let translator = CreateTableExprTranslator;
-    let sql = translator.translate(&create_expr)?;
-    let _result = sqlx::query(&sql)
-        .execute(&ctx.greptime)
-        .await
-        .context(error::ExecuteQuerySnafu { sql: &sql })?;
-
-    let table_ctx = Arc::new(TableContext::from(&create_expr));
+async fn insert_values<R: Rng + 'static>(
+    ctx: &FuzzContext,
+    input: FuzzInput,
+    table_ctx: &TableContextRef,
+    rng: &mut R,
+    insert_exprs: &[InsertIntoExpr],
+) -> Result<()> {
     // Inserts data into the table
-    let insert_exprs = generate_insert_exprs(input, &mut rng, table_ctx.clone())?;
-    for insert_expr in &insert_exprs {
+    for insert_expr in insert_exprs {
         let translator = InsertIntoExprTranslator;
         let sql = translator.translate(insert_expr)?;
         let result = ctx
@@ -168,63 +161,82 @@ async fn execute_region_migration(ctx: FuzzContext, input: FuzzInput) -> Result<
             }
         );
         if rng.gen_bool(0.2) {
-            flush_memtable(&ctx.greptime, &create_expr.table_name).await?;
+            flush_memtable(&ctx.greptime, &table_ctx.name).await?;
         }
         if rng.gen_bool(0.1) {
-            compact_table(&ctx.greptime, &create_expr.table_name).await?;
+            compact_table(&ctx.greptime, &table_ctx.name).await?;
         }
     }
+    Ok(())
+}
 
-    // Fetches region distribution
-    let partitions = fetch_partitions(&ctx.greptime, table_ctx.name.clone()).await?;
-    let num_partitions = partitions.len();
-    let region_distribution = region_distribution(partitions);
-    info!("Region distribution: {region_distribution:?}");
-    let datanodes = fetch_nodes(&ctx.greptime)
-        .await?
-        .into_iter()
-        .flat_map(|node| {
-            if node.peer_type == PEER_TYPE_DATANODE {
-                Some(node)
-            } else {
-                None
-            }
-        })
-        .collect::<Vec<_>>();
-    info!("List datanodes: {:?}", datanodes);
+async fn validate_insert_exprs(
+    ctx: &FuzzContext,
+    table_ctx: &TableContextRef,
+    insert_exprs: &[InsertIntoExpr],
+) -> Result<()> {
+    info!("Validating rows");
+    let ts_column = table_ctx.timestamp_column().unwrap();
+    for (idx, insert_expr) in insert_exprs[0..insert_exprs.len() - 1].iter().enumerate() {
+        let ts_column_idx = insert_expr.timestamp_column_idx().unwrap();
+        let ts_value = insert_expr.values_list[0][ts_column_idx].clone();
+        let next_batch_ts_column_idx = insert_exprs[idx + 1].timestamp_column_idx().unwrap();
+        let next_batch_ts = insert_exprs[idx + 1].values_list[0][next_batch_ts_column_idx].clone();
 
-    // Generates region migration task.
-    let mut migrations = Vec::with_capacity(num_partitions);
-    let mut new_distribution: BTreeMap<u64, HashSet<_>> = BTreeMap::new();
-    for (datanode_id, regions) in region_distribution {
-        let step = rng.gen_range(1..datanodes.len());
-        for region in regions {
-            let to_peer = (datanode_id + step as u64) % datanodes.len() as u64;
-            new_distribution.entry(to_peer).or_default().insert(region);
-            migrations.push(Migration {
-                from_peer: datanode_id,
-                to_peer,
-                region_id: region,
-            })
-        }
+        let primary_keys_idx = insert_expr.primary_key_column_idx();
+        let column_list = format_columns(&insert_expr.columns);
+        let primary_keys_column_list = format_columns(&insert_expr.primary_key_columns());
+        let select_sql = format!(
+            "SELECT {} FROM {} WHERE {} >= {} AND {} < {} ORDER BY {};",
+            column_list,
+            table_ctx.name,
+            ts_column.name,
+            ts_value,
+            ts_column.name,
+            next_batch_ts,
+            primary_keys_column_list
+        );
+        info!("Executing sql: {select_sql}");
+        let fetched_rows = ctx.greptime.fetch_all(select_sql.as_str()).await.unwrap();
+        let mut expected_rows = replace_default(&insert_expr.values_list, table_ctx, insert_expr);
+        sort_by_primary_keys(&mut expected_rows, primary_keys_idx);
+        validator::row::assert_eq::<MySql>(&insert_expr.columns, &fetched_rows, &expected_rows)?;
     }
+    let insert_expr = insert_exprs.last().unwrap();
+    let ts_column_idx = insert_expr.timestamp_column_idx().unwrap();
+    let ts_value = insert_expr.values_list[0][ts_column_idx].clone();
+    let primary_keys_idx = insert_expr.primary_key_column_idx();
+    let column_list = format_columns(&insert_expr.columns);
+    let primary_keys_column_list = format_columns(&insert_expr.primary_key_columns());
+    let select_sql = format!(
+        "SELECT {} FROM {} WHERE {} >= {} ORDER BY {};",
+        column_list, table_ctx.name, ts_column.name, ts_value, primary_keys_column_list
+    );
+    info!("Executing sql: {select_sql}");
+    let fetched_rows = ctx.greptime.fetch_all(select_sql.as_str()).await.unwrap();
+    let mut expected_rows = replace_default(&insert_expr.values_list, table_ctx, insert_expr);
+    sort_by_primary_keys(&mut expected_rows, primary_keys_idx);
+    validator::row::assert_eq::<MySql>(&insert_expr.columns, &fetched_rows, &expected_rows)?;
 
+    Ok(())
+}
+
+async fn migrate_regions(ctx: &FuzzContext, migrations: &[Migration]) -> Result<()> {
     let mut procedure_ids = Vec::with_capacity(migrations.len());
-    // Triggers region migrations
+
     for Migration {
         from_peer,
         to_peer,
         region_id,
-    } in &migrations
+    } in migrations
     {
         let procedure_id =
             migrate_region(&ctx.greptime, region_id.as_u64(), *from_peer, *to_peer, 240).await;
         info!("Migrating region: {region_id} from {from_peer} to {to_peer}, procedure: {procedure_id}");
         procedure_ids.push(procedure_id);
     }
-    info!("Excepted new region distribution: {new_distribution:?}");
 
-    for (migration, procedure_id) in migrations.into_iter().zip(procedure_ids) {
+    for (migration, procedure_id) in migrations.iter().zip(procedure_ids) {
         info!("Waits for migration: {migration:?}");
         let region_id = migration.region_id.as_u64();
         wait_condition_fn(
@@ -249,49 +261,86 @@ async fn execute_region_migration(ctx: FuzzContext, input: FuzzInput) -> Result<
         .await;
     }
 
-    // Values validation
-    info!("Validating rows");
-    let ts_column = table_ctx.timestamp_column().unwrap();
-    for (idx, insert_expr) in insert_exprs[0..insert_exprs.len() - 1].iter().enumerate() {
-        let ts_column_idx = insert_expr.timestamp_column_idx().unwrap();
-        let ts_value = insert_expr.values_list[0][ts_column_idx].clone();
-        let next_batch_ts_column_idx = insert_exprs[idx + 1].timestamp_column_idx().unwrap();
-        let next_batch_ts = insert_exprs[idx + 1].values_list[0][next_batch_ts_column_idx].clone();
+    Ok(())
+}
 
-        let primary_keys_idx = insert_expr.primary_key_column_idx();
-        let column_list = format_columns(&insert_expr.columns);
-        let primary_keys_column_list = format_columns(&insert_expr.primary_key_columns());
-        let select_sql = format!(
-            "SELECT {} FROM {} WHERE {} >= {} AND {} < {} ORDER BY {};",
-            column_list,
-            create_expr.table_name,
-            ts_column.name,
-            ts_value,
-            ts_column.name,
-            next_batch_ts,
-            primary_keys_column_list
-        );
-        info!("Executing sql: {select_sql}");
-        let fetched_rows = ctx.greptime.fetch_all(select_sql.as_str()).await.unwrap();
-        let mut expected_rows = replace_default(&insert_expr.values_list, &table_ctx, insert_expr);
-        sort_by_primary_keys(&mut expected_rows, primary_keys_idx);
-        validator::row::assert_eq::<MySql>(&insert_expr.columns, &fetched_rows, &expected_rows)?;
+async fn execute_region_migration(ctx: FuzzContext, input: FuzzInput) -> Result<()> {
+    info!("input: {:?}", input);
+    let mut rng = ChaChaRng::seed_from_u64(input.seed);
+
+    let create_expr = generate_create_expr(input, &mut rng)?;
+    let translator = CreateTableExprTranslator;
+    let sql = translator.translate(&create_expr)?;
+    let _result = sqlx::query(&sql)
+        .execute(&ctx.greptime)
+        .await
+        .context(error::ExecuteQuerySnafu { sql: &sql })?;
+
+    let table_ctx = Arc::new(TableContext::from(&create_expr));
+    let mut insert_exprs = generate_insert_exprs(input, &mut rng, table_ctx.clone())?;
+    let remaining_insert_exprs = insert_exprs.split_off(insert_exprs.len() / 2);
+    insert_values(&ctx, input, &table_ctx, &mut rng, &insert_exprs).await?;
+
+    // Fetches region distribution
+    let partitions = fetch_partitions(&ctx.greptime, table_ctx.name.clone()).await?;
+    let num_partitions = partitions.len();
+    let region_distribution = region_distribution(partitions);
+    info!("Region distribution: {region_distribution:?}");
+    let datanodes = fetch_nodes(&ctx.greptime)
+        .await?
+        .into_iter()
+        .flat_map(|node| {
+            if node.peer_type == PEER_TYPE_DATANODE {
+                Some(node)
+            } else {
+                None
+            }
+        })
+        .collect::<Vec<_>>();
+    info!("List datanodes: {:?}", datanodes);
+
+    // Generates region migration task.
+    let mut migrations = Vec::with_capacity(num_partitions);
+    let mut new_distribution: BTreeMap<u64, HashSet<_>> = BTreeMap::new();
+    for (datanode_id, regions) in region_distribution {
+        let step = rng.gen_range(1..datanodes.len());
+        for region in regions {
+            let to_peer = (datanode_id + step as u64) % datanodes.len() as u64;
+            new_distribution.entry(to_peer).or_default().insert(region);
+            migrations.push(Migration {
+                from_peer: datanode_id,
+                to_peer,
+                region_id: region,
+            })
+        }
     }
-    let insert_expr = insert_exprs.last().unwrap();
-    let ts_column_idx = insert_expr.timestamp_column_idx().unwrap();
-    let ts_value = insert_expr.values_list[0][ts_column_idx].clone();
-    let primary_keys_idx = insert_expr.primary_key_column_idx();
-    let column_list = format_columns(&insert_expr.columns);
-    let primary_keys_column_list = format_columns(&insert_expr.primary_key_columns());
-    let select_sql = format!(
-        "SELECT {} FROM {} WHERE {} >= {} ORDER BY {};",
-        column_list, create_expr.table_name, ts_column.name, ts_value, primary_keys_column_list
-    );
-    info!("Executing sql: {select_sql}");
-    let fetched_rows = ctx.greptime.fetch_all(select_sql.as_str()).await.unwrap();
-    let mut expected_rows = replace_default(&insert_expr.values_list, &table_ctx, insert_expr);
-    sort_by_primary_keys(&mut expected_rows, primary_keys_idx);
-    validator::row::assert_eq::<MySql>(&insert_expr.columns, &fetched_rows, &expected_rows)?;
+
+    info!("Excepted new region distribution: {new_distribution:?}");
+    // Triggers region migrations
+    migrate_regions(&ctx, &migrations).await?;
+    // Values validation
+    validate_insert_exprs(&ctx, &table_ctx, &insert_exprs).await?;
+
+    insert_values(&ctx, input, &table_ctx, &mut rng, &remaining_insert_exprs).await?;
+    // Recovers region distribution
+    let migrations = migrations
+        .into_iter()
+        .map(
+            |Migration {
+                 from_peer,
+                 to_peer,
+                 region_id,
+             }| Migration {
+                from_peer: to_peer,
+                to_peer: from_peer,
+                region_id,
+            },
+        )
+        .collect::<Vec<_>>();
+    // Triggers region migrations
+    migrate_regions(&ctx, &migrations).await?;
+    // Values validation
+    validate_insert_exprs(&ctx, &table_ctx, &remaining_insert_exprs).await?;
 
     // Cleans up
     let sql = format!("DROP TABLE {}", table_ctx.name);