From 4c06e26d8593f5d68cfe6a8981bcb1165b682dbd Mon Sep 17 00:00:00 2001
From: Andrey Smirnov <smirnov.andrey@gmail.com>
Date: Thu, 23 Feb 2017 01:01:17 +0300
Subject: [PATCH] Throttle compaction on temporary DB

---
 database/leveldb.go | 18 ++++++++++++++----
 deb/contents.go     |  2 +-
 2 files changed, 15 insertions(+), 5 deletions(-)

diff --git a/database/leveldb.go b/database/leveldb.go
index ab90e1ff..8b065725 100644
--- a/database/leveldb.go
+++ b/database/leveldb.go
@@ -51,18 +51,24 @@ var (
 	_ Storage = &levelDB{}
 )
 
-func internalOpen(path string) (*leveldb.DB, error) {
+func internalOpen(path string, throttleCompaction bool) (*leveldb.DB, error) {
 	o := &opt.Options{
 		Filter:                 filter.NewBloomFilter(10),
 		OpenFilesCacheCapacity: 256,
 	}
 
+	if throttleCompaction {
+		o.CompactionL0Trigger = 32
+		o.WriteL0PauseTrigger = 96
+		o.WriteL0SlowdownTrigger = 64
+	}
+
 	return leveldb.OpenFile(path, o)
 }
 
 // OpenDB opens (creates) LevelDB database
 func OpenDB(path string) (Storage, error) {
-	db, err := internalOpen(path)
+	db, err := internalOpen(path, false)
 	if err != nil {
 		return nil, err
 	}
@@ -94,7 +100,11 @@ func (l *levelDB) CreateTemporary() (Storage, error) {
 		return nil, err
 	}
 
-	return OpenDB(tempdir)
+	db, err := internalOpen(tempdir, true)
+	if err != nil {
+		return nil, err
+	}
+	return &levelDB{db: db, path: tempdir}, nil
 }
 
 // Get key value from database
@@ -212,7 +222,7 @@ func (l *levelDB) ReOpen() error {
 	}
 
 	var err error
-	l.db, err = internalOpen(l.path)
+	l.db, err = internalOpen(l.path, false)
 	return err
 }
 
diff --git a/deb/contents.go b/deb/contents.go
index 30dc3e0e..e3dc8eb7 100644
--- a/deb/contents.go
+++ b/deb/contents.go
@@ -50,7 +50,7 @@ func (index *ContentsIndex) Empty() bool {
 // WriteTo dumps sorted mapping of files to qualified package names
 func (index *ContentsIndex) WriteTo(w io.Writer) (int64, error) {
 	// For performance reasons push method wrote on key per path and package
-	// in this method we now need to merge all pkg with have the same path
+	// in this method we now need to merge all packages which have the same path
 	// and write it to contents index file
 
 	var n int64