From 036caeb21a8b3278c0c0c8343d6718d025b2b543 Mon Sep 17 00:00:00 2001
From: Rob Bavey <rob.bavey@elastic.co>
Date: Thu, 15 Jun 2017 10:02:22 -0400
Subject: [PATCH] Avoid unnecessary seeks in seekToNextEventPosition

When an exact match is found during the binary search for the
next event, use the matching block instead of seeking from the
'low' block.

Add toString method to DLQEntry

Fixes #7464
---
 .../src/main/java/org/logstash/DLQEntry.java          | 11 +++++++++++
 .../java/org/logstash/common/io/RecordIOReader.java   |  7 +++++--
 2 files changed, 16 insertions(+), 2 deletions(-)

diff --git a/logstash-core/src/main/java/org/logstash/DLQEntry.java b/logstash-core/src/main/java/org/logstash/DLQEntry.java
index 786249015..fd44dc534 100644
--- a/logstash-core/src/main/java/org/logstash/DLQEntry.java
+++ b/logstash-core/src/main/java/org/logstash/DLQEntry.java
@@ -112,4 +112,15 @@ public class DLQEntry implements Cloneable, Serializable, Queueable {
     public Timestamp getEntryTime() {
         return entryTime;
     }
+
+    @Override
+    public String toString() {
+        return "DLQEntry{" +
+                "event=" + event +
+                ", pluginType='" + pluginType + '\'' +
+                ", pluginId='" + pluginId + '\'' +
+                ", reason='" + reason + '\'' +
+                ", entryTime=" + entryTime +
+                '}';
+    }
 }
diff --git a/logstash-core/src/main/java/org/logstash/common/io/RecordIOReader.java b/logstash-core/src/main/java/org/logstash/common/io/RecordIOReader.java
index 9df8271c6..a21f60a32 100644
--- a/logstash-core/src/main/java/org/logstash/common/io/RecordIOReader.java
+++ b/logstash-core/src/main/java/org/logstash/common/io/RecordIOReader.java
@@ -43,6 +43,7 @@ public class RecordIOReader {
     private int currentBlockSizeReadFromChannel;
     private final Path path;
     private long channelPosition;
+    private static final int UNSET = -1;
 
     public RecordIOReader(Path path) throws IOException {
         this.path = path;
@@ -74,7 +75,7 @@ public class RecordIOReader {
     }
 
     public <T> byte[] seekToNextEventPosition(T target, Function<byte[], T> keyExtractor, Comparator<T> keyComparator) throws IOException {
-        int matchingBlock;
+        int matchingBlock = UNSET;
         int lowBlock = 0;
         int highBlock = (int) (channel.size() - VERSION_SIZE) / BLOCK_SIZE;
 
@@ -96,7 +97,9 @@ public class RecordIOReader {
                 break;
             }
         }
-        matchingBlock = lowBlock;
+        if (matchingBlock == UNSET) {
+            matchingBlock = lowBlock;
+        }
 
         // now sequential scan to event
         seekToBlock(matchingBlock);