From e4358bf4d32215a3fe6d6fbed7001feba873d00a Mon Sep 17 00:00:00 2001
From: Ti Chi Robot <ti-community-prow-bot@tidb.io>
Date: Tue, 6 Dec 2022 14:12:03 +0800
Subject: [PATCH] Optimize region not find (#2575) (#2596)

---
 .../com/pingcap/tikv/region/RegionManager.java    | 15 +++++++++++++--
 .../pingcap/tikv/region/RegionStoreClient.java    | 10 ++++++++--
 2 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/tikv-client/src/main/java/com/pingcap/tikv/region/RegionManager.java b/tikv-client/src/main/java/com/pingcap/tikv/region/RegionManager.java
index d6fd12803e..e24f5e06a7 100644
--- a/tikv-client/src/main/java/com/pingcap/tikv/region/RegionManager.java
+++ b/tikv-client/src/main/java/com/pingcap/tikv/region/RegionManager.java
@@ -189,6 +189,10 @@ public void invalidateRegion(TiRegion region) {
     cache.invalidateRegion(region);
   }
 
+  public void invalidateRange(ByteString startKey, ByteString endKey) {
+    cache.invalidateRange(startKey,endKey);
+  }
+
   public static class RegionCache {
     // private final Map<Long, TiRegion> regionCache;
     private final Map<Long, Store> storeCache;
@@ -253,19 +257,26 @@ private synchronized TiRegion getRegionFromCache(Key key) {
 
     private synchronized void invalidateRange(ByteString startKey, ByteString endKey) {
       regionCache.remove(makeRange(startKey, endKey));
+      if (logger.isDebugEnabled()) {
+        logger.debug(String.format("invalidateRange success, startKey[%s], endKey[%s]", startKey, endKey));
+      }
     }
 
     /** Removes region associated with regionId from regionCache. */
     public synchronized void invalidateRegion(TiRegion region) {
       try {
         if (logger.isDebugEnabled()) {
-          logger.debug(String.format("invalidateRegion ID[%s]", region.getId()));
+          logger.debug(String.format("invalidateRegion ID[%s] start", region.getId()));
         }
         TiRegion oldRegion = regionCache.get(getEncodedKey(region.getStartKey()));
         if (oldRegion != null && oldRegion.equals(region)) {
           regionCache.remove(makeRange(region.getStartKey(), region.getEndKey()));
+          if (logger.isDebugEnabled()) {
+            logger.debug(String.format("invalidateRegion ID[%s] success", region.getId()));
+          }
         }
-      } catch (Exception ignore) {
+      } catch (Exception e) {
+        logger.warn("invalidateRegion failed", e);
       }
     }
 
diff --git a/tikv-client/src/main/java/com/pingcap/tikv/region/RegionStoreClient.java b/tikv-client/src/main/java/com/pingcap/tikv/region/RegionStoreClient.java
index bb38279ce8..238cc6f918 100644
--- a/tikv-client/src/main/java/com/pingcap/tikv/region/RegionStoreClient.java
+++ b/tikv-client/src/main/java/com/pingcap/tikv/region/RegionStoreClient.java
@@ -673,7 +673,7 @@ public List<RangeSplitter.RegionTask> coprocess(
             forWrite);
     Coprocessor.Response resp =
         callWithRetry(backOffer, TikvGrpc.getCoprocessorMethod(), reqToSend, handler);
-    return handleCopResponse(backOffer, resp, ranges, responseQueue, startTs);
+    return handleCopResponse(backOffer, resp, ranges, responseQueue, startTs, region);
   }
 
   // handleCopResponse checks coprocessor Response for region split and lock,
@@ -685,7 +685,8 @@ private List<RangeSplitter.RegionTask> handleCopResponse(
       Coprocessor.Response response,
       List<Coprocessor.KeyRange> ranges,
       Queue<SelectResponse> responseQueue,
-      long startTs) {
+      long startTs,
+      TiRegion region) {
     boolean forWrite = false;
     if (response == null) {
       // Send request failed, reasons may:
@@ -704,6 +705,11 @@ private List<RangeSplitter.RegionTask> handleCopResponse(
       backOffer.doBackOff(
           BackOffFunction.BackOffFuncType.BoRegionMiss, new GrpcException(regionError.toString()));
       logger.warn("Re-splitting region task due to region error:" + regionError.getMessage());
+      // we need to invalidate cache when region not find
+      if (regionError.hasRegionNotFound()) {
+        logger.info("invalidateRange when Re-splitting region task because of region not find.");
+        this.regionManager.invalidateRange(region.getStartKey(),region.getEndKey());
+      }
       // Split ranges
       return RangeSplitter.newSplitter(this.regionManager).splitRangeByRegion(ranges, storeType);
     }