From ae2b77a0e52c0ebfd2879931b24bd3e51ee29e5a Mon Sep 17 00:00:00 2001
From: Chen Liang <cliang@apache.org>
Date: Mon, 9 Oct 2017 14:52:50 -0700
Subject: [PATCH] HDFS-12546. Ozone: DB listing operation performance
 improvement. Contributed by Weiwei Yang.

---
 .../ozone/container/common/impl/KeyManagerImpl.java       | 2 +-
 .../statemachine/background/BlockDeletingService.java     | 2 +-
 .../apache/hadoop/ozone/ksm/KSMMetadataManagerImpl.java   | 8 ++++----
 .../hadoop/ozone/scm/container/ContainerMapping.java      | 2 +-
 4 files changed, 7 insertions(+), 7 deletions(-)

diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/impl/KeyManagerImpl.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/impl/KeyManagerImpl.java
index 7fff0a34b4..98661b869d 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/impl/KeyManagerImpl.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/impl/KeyManagerImpl.java
@@ -180,7 +180,7 @@ public List<KeyData> listKey(
         DFSUtil.string2Bytes(startKey);
     MetadataKeyFilter prefixFilter = new KeyPrefixFilter(prefix);
     List<Map.Entry<byte[], byte[]>> range =
-        db.getRangeKVs(startKeyInBytes, count, prefixFilter);
+        db.getSequentialRangeKVs(startKeyInBytes, count, prefixFilter);
     for (Map.Entry<byte[], byte[]> entry : range) {
       String keyName = KeyUtils.getKeyName(entry.getKey());
       KeyData value = KeyUtils.getKeyData(entry.getValue());
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/background/BlockDeletingService.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/background/BlockDeletingService.java
index 644e928bab..a90b1e9c16 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/background/BlockDeletingService.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/container/common/statemachine/background/BlockDeletingService.java
@@ -175,7 +175,7 @@ public BackgroundTaskResult call() throws Exception {
       KeyPrefixFilter filter = new KeyPrefixFilter(
           OzoneConsts.DELETING_KEY_PREFIX);
       List<Map.Entry<byte[], byte[]>> toDeleteBlocks =
-          meta.getRangeKVs(null, blockLimitPerTask, filter);
+          meta.getSequentialRangeKVs(null, blockLimitPerTask, filter);
       if (toDeleteBlocks.isEmpty()) {
         LOG.debug("No under deletion block found in container : {}",
             containerData.getContainerName());
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/ksm/KSMMetadataManagerImpl.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/ksm/KSMMetadataManagerImpl.java
index a24d279e17..f729bfe9f4 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/ksm/KSMMetadataManagerImpl.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/ksm/KSMMetadataManagerImpl.java
@@ -347,13 +347,13 @@ public List<KsmKeyInfo> listKeys(String volumeName, String bucketName,
     if (!Strings.isNullOrEmpty(startKey)) {
       //Since we are excluding start key from the result,
       // the maxNumOfBuckets is incremented.
-      rangeResult = store.getRangeKVs(
+      rangeResult = store.getSequentialRangeKVs(
           getDBKeyBytes(volumeName, bucketName, startKey),
           maxKeys + 1, filter);
       //Remove start key from result.
       rangeResult.remove(0);
     } else {
-      rangeResult = store.getRangeKVs(null, maxKeys, filter);
+      rangeResult = store.getSequentialRangeKVs(null, maxKeys, filter);
     }
 
     for (Map.Entry<byte[], byte[]> entry : rangeResult) {
@@ -440,7 +440,7 @@ private VolumeList getAllVolumes() throws IOException {
     // it should be fine to scan all users in db and return us a
     // list of volume names in string per user.
     List<Map.Entry<byte[], byte[]>> rangeKVs = store
-        .getRangeKVs(null, Integer.MAX_VALUE, filter);
+        .getSequentialRangeKVs(null, Integer.MAX_VALUE, filter);
 
     VolumeList.Builder builder = VolumeList.newBuilder();
     for (Map.Entry<byte[], byte[]> entry : rangeKVs) {
@@ -458,7 +458,7 @@ public List<BlockGroup> getPendingDeletionKeys(final int count)
     final MetadataKeyFilter deletingKeyFilter =
         new KeyPrefixFilter(DELETING_KEY_PREFIX);
     List<Map.Entry<byte[], byte[]>> rangeResult =
-        store.getRangeKVs(null, count, deletingKeyFilter);
+        store.getSequentialRangeKVs(null, count, deletingKeyFilter);
     for (Map.Entry<byte[], byte[]> entry : rangeResult) {
       KsmKeyInfo info =
           KsmKeyInfo.getFromProtobuf(KeyInfo.parseFrom(entry.getValue()));
diff --git a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/container/ContainerMapping.java b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/container/ContainerMapping.java
index ad1d3c9f91..c6a0f31026 100644
--- a/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/container/ContainerMapping.java
+++ b/hadoop-hdfs-project/hadoop-hdfs/src/main/java/org/apache/hadoop/ozone/scm/container/ContainerMapping.java
@@ -145,7 +145,7 @@ public List<Pipeline> listContainer(String startName, String prefixName,
       byte[] startKey = startName == null ? null : DFSUtil.string2Bytes(
           startName);
       List<Map.Entry<byte[], byte[]>> range =
-          containerStore.getRangeKVs(startKey, count, prefixFilter);
+          containerStore.getSequentialRangeKVs(startKey, count, prefixFilter);
 
       // Transform the values into the pipelines.
       // TODO: return list of ContainerInfo instead of pipelines.