From 59244447e3123da87fc3f3ade859d85f69165f40 Mon Sep 17 00:00:00 2001
From: Ming Zhao <mingzhao@fb.com>
Date: Fri, 1 Feb 2019 09:19:09 -0800
Subject: [PATCH] Zero seqnum of final key / drop final tombstone when
 compacting to bottommost level

Summary: Pull Request resolved: https://github.com/facebook/rocksdb/pull/4927

Differential Revision: D13889458

Pulled By: mzhaom

fbshipit-source-id: d6b66db85901a9eb90748fba6a9dc4e7457b9c5e
---
 db/compaction_iterator.cc       |  3 +--
 db/compaction_job_test.cc       | 14 +++++++-------
 db/db_compaction_filter_test.cc |  4 ++--
 3 files changed, 10 insertions(+), 11 deletions(-)

diff --git a/db/compaction_iterator.cc b/db/compaction_iterator.cc
index 675e88d63..8721634f8 100644
--- a/db/compaction_iterator.cc
+++ b/db/compaction_iterator.cc
@@ -634,8 +634,7 @@ void CompactionIterator::PrepareOutput() {
   // KeyNotExistsBeyondOutputLevel() return true?
   if ((compaction_ != nullptr && !compaction_->allow_ingest_behind()) &&
       ikeyNotNeededForIncrementalSnapshot() && bottommost_level_ && valid_ &&
-      IN_EARLIEST_SNAPSHOT(ikey_.sequence) && ikey_.type != kTypeMerge &&
-      !cmp_->Equal(compaction_->GetLargestUserKey(), ikey_.user_key)) {
+      IN_EARLIEST_SNAPSHOT(ikey_.sequence) && ikey_.type != kTypeMerge) {
     assert(ikey_.type != kTypeDeletion && ikey_.type != kTypeSingleDeletion);
     ikey_.sequence = 0;
     current_key_.UpdateInternalKey(0, ikey_.type);
diff --git a/db/compaction_job_test.cc b/db/compaction_job_test.cc
index 16114ccaa..d41b4d1ac 100644
--- a/db/compaction_job_test.cc
+++ b/db/compaction_job_test.cc
@@ -172,7 +172,7 @@ class CompactionJobTest : public testing::Test {
         // This is how the key will look like once it's written in bottommost
         // file
         InternalKey bottommost_internal_key(
-            key, (key == "9999") ? sequence_number : 0, kTypeValue);
+            key, 0, kTypeValue);
 
         if (corrupt_id(k)) {
           test::CorruptKeyType(&internal_key);
@@ -379,7 +379,7 @@ TEST_F(CompactionJobTest, SimpleOverwrite) {
 
   auto expected_results =
       mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), "val2"},
-                          {KeyStr("b", 4U, kTypeValue), "val3"}});
+                          {KeyStr("b", 0U, kTypeValue), "val3"}});
 
   SetLastSequence(4U);
   auto files = cfd_->current()->storage_info()->LevelFiles(0);
@@ -432,7 +432,7 @@ TEST_F(CompactionJobTest, SimpleMerge) {
 
   auto expected_results =
       mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), "3,4,5"},
-                          {KeyStr("b", 2U, kTypeValue), "1,2"}});
+                          {KeyStr("b", 0U, kTypeValue), "1,2"}});
 
   SetLastSequence(5U);
   auto files = cfd_->current()->storage_info()->LevelFiles(0);
@@ -456,7 +456,7 @@ TEST_F(CompactionJobTest, NonAssocMerge) {
 
   auto expected_results =
       mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), "3,4,5"},
-                          {KeyStr("b", 2U, kTypeValue), "1,2"}});
+                          {KeyStr("b", 0U, kTypeValue), "1,2"}});
 
   SetLastSequence(5U);
   auto files = cfd_->current()->storage_info()->LevelFiles(0);
@@ -483,7 +483,7 @@ TEST_F(CompactionJobTest, MergeOperandFilter) {
 
   auto expected_results =
       mock::MakeMockFile({{KeyStr("a", 0U, kTypeValue), test::EncodeInt(8U)},
-                          {KeyStr("b", 2U, kTypeValue), test::EncodeInt(2U)}});
+                          {KeyStr("b", 0U, kTypeValue), test::EncodeInt(2U)}});
 
   SetLastSequence(5U);
   auto files = cfd_->current()->storage_info()->LevelFiles(0);
@@ -746,7 +746,7 @@ TEST_F(CompactionJobTest, SingleDeleteZeroSeq) {
   AddMockFile(file2);
 
   auto expected_results = mock::MakeMockFile({
-      {KeyStr("dummy", 5U, kTypeValue), "val2"},
+      {KeyStr("dummy", 0U, kTypeValue), "val2"},
   });
 
   SetLastSequence(22U);
@@ -930,7 +930,7 @@ TEST_F(CompactionJobTest, CorruptionAfterDeletion) {
       mock::MakeMockFile({{test::KeyStr("A", 0U, kTypeValue), "val3"},
                           {test::KeyStr("a", 0U, kTypeValue, true), "val"},
                           {test::KeyStr("b", 0U, kTypeValue, true), "val"},
-                          {test::KeyStr("c", 1U, kTypeValue), "val2"}});
+                          {test::KeyStr("c", 0U, kTypeValue), "val2"}});
 
   SetLastSequence(6U);
   auto files = cfd_->current()->storage_info()->LevelFiles(0);
diff --git a/db/db_compaction_filter_test.cc b/db/db_compaction_filter_test.cc
index 25045d01d..a19fde0b7 100644
--- a/db/db_compaction_filter_test.cc
+++ b/db/db_compaction_filter_test.cc
@@ -357,7 +357,7 @@ TEST_F(DBTestCompactionFilter, CompactionFilter) {
     }
   }
   ASSERT_EQ(total, 100000);
-  ASSERT_EQ(count, 1);
+  ASSERT_EQ(count, 0);
 
   // overwrite all the 100K keys once again.
   for (int i = 0; i < 100000; i++) {
@@ -664,7 +664,7 @@ TEST_F(DBTestCompactionFilter, CompactionFilterContextManual) {
       iter->Next();
     }
     ASSERT_EQ(total, 700);
-    ASSERT_EQ(count, 1);
+    ASSERT_EQ(count, 0);
   }
 }
 #endif  // ROCKSDB_LITE