From dae2f19cd8d72b7c1b8f7daa2bc2316856ce7f62 Mon Sep 17 00:00:00 2001
From: Bilal Akhtar <bilal@cockroachlabs.com>
Date: Mon, 19 Oct 2020 15:52:11 -0400
Subject: [PATCH] storage: Use batches for direct RocksDB mutations

Currently, doing direct mutations on a RocksDB instance bypasses
custom batching / syncing logic that we've built on top of it.
This, or something internal to RocksDB, started leading to some bugs
when all direct mutations started passing in WriteOptions.sync = true
(see #55240 for when this change went in).

In this change, direct mutations still commit the batch with sync=true
to guarantee WAL syncing, but they go through the batch commit pipeline
too, just like the vast majority of operations already do.

Fixes #55362.

Release note: None.
---
 pkg/storage/rocksdb.go | 52 ++++++++++++++++++++++++++++++++++++------
 1 file changed, 45 insertions(+), 7 deletions(-)

diff --git a/pkg/storage/rocksdb.go b/pkg/storage/rocksdb.go
index 3585e1717ee2..85619f1d98e4 100644
--- a/pkg/storage/rocksdb.go
+++ b/pkg/storage/rocksdb.go
@@ -508,7 +508,12 @@ func (r *RocksDB) Attrs() roachpb.Attributes {
 //
 // It is safe to modify the contents of the arguments after Put returns.
 func (r *RocksDB) Put(key MVCCKey, value []byte) error {
-	return dbPut(r.rdb, key, value)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	if err := b.Put(key, value); err != nil {
+		return err
+	}
+	return b.Commit(true)
 }
 
 // Merge implements the RocksDB merge operator using the function goMergeInit
@@ -519,7 +524,12 @@ func (r *RocksDB) Put(key MVCCKey, value []byte) error {
 //
 // It is safe to modify the contents of the arguments after Merge returns.
 func (r *RocksDB) Merge(key MVCCKey, value []byte) error {
-	return dbMerge(r.rdb, key, value)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	if err := b.Merge(key, value); err != nil {
+		return err
+	}
+	return b.Commit(true)
 }
 
 // LogData is part of the Writer interface.
@@ -541,7 +551,12 @@ func (r *RocksDB) LogLogicalOp(op MVCCLogicalOpType, details MVCCLogicalOpDetail
 // It is safe to modify the contents of the arguments after ApplyBatchRepr
 // returns.
 func (r *RocksDB) ApplyBatchRepr(repr []byte, sync bool) error {
-	return dbApplyBatchRepr(r.rdb, repr, sync)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	if err := b.ApplyBatchRepr(repr, sync); err != nil {
+		return err
+	}
+	return b.Commit(sync)
 }
 
 // Get returns the value for the given key.
@@ -560,14 +575,24 @@ func (r *RocksDB) GetProto(
 //
 // It is safe to modify the contents of the arguments after Clear returns.
 func (r *RocksDB) Clear(key MVCCKey) error {
-	return dbClear(r.rdb, key)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	if err := b.Clear(key); err != nil {
+		return err
+	}
+	return b.Commit(true)
 }
 
 // SingleClear removes the most recent item from the db with the given key.
 //
 // It is safe to modify the contents of the arguments after SingleClear returns.
 func (r *RocksDB) SingleClear(key MVCCKey) error {
-	return dbSingleClear(r.rdb, key)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	if err := b.SingleClear(key); err != nil {
+		return err
+	}
+	return b.Commit(true)
 }
 
 // ClearRange removes a set of entries, from start (inclusive) to end
@@ -575,7 +600,12 @@ func (r *RocksDB) SingleClear(key MVCCKey) error {
 //
 // It is safe to modify the contents of the arguments after ClearRange returns.
 func (r *RocksDB) ClearRange(start, end MVCCKey) error {
-	return dbClearRange(r.rdb, start, end)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	if err := b.ClearRange(start, end); err != nil {
+		return err
+	}
+	return b.Commit(true)
 }
 
 // ClearIterRange removes a set of entries, from start (inclusive) to end
@@ -584,7 +614,15 @@ func (r *RocksDB) ClearRange(start, end MVCCKey) error {
 // It is safe to modify the contents of the arguments after ClearIterRange
 // returns.
 func (r *RocksDB) ClearIterRange(iter Iterator, start, end roachpb.Key) error {
-	return dbClearIterRange(r.rdb, iter, start, end)
+	b := r.NewWriteOnlyBatch()
+	defer b.Close()
+	err := r.Iterate(start, end, func(keyValue MVCCKeyValue) error {
+		return b.Clear(keyValue.Key)
+	})
+	if err != nil {
+		return err
+	}
+	return b.Commit(true)
 }
 
 // Iterate iterates from start to end keys, invoking f on each