From c067fc0618923a9e1399973eb2333c38a5b6aa3b Mon Sep 17 00:00:00 2001
From: "Sascha L. Teichmann" <sascha.teichmann@intevation.de>
Date: Sat, 15 Apr 2017 13:17:31 +0200
Subject: [PATCH] Backed out changeset 2f388b07f19a (no measurable effect)

---
 cmd/mtredisalize/leveldb.go | 33 ---------------------------------
 1 file changed, 33 deletions(-)

diff --git a/cmd/mtredisalize/leveldb.go b/cmd/mtredisalize/leveldb.go
index 1e5abd6..591afbd 100644
--- a/cmd/mtredisalize/leveldb.go
+++ b/cmd/mtredisalize/leveldb.go
@@ -6,7 +6,6 @@ package main
 
 import (
 	"log"
-	"sync"
 
 	"bitbucket.org/s_l_teichmann/mtsatellite/common"
 
@@ -22,9 +21,6 @@ type LevelDBBackend struct {
 	decoder     common.KeyTranscoder
 
 	changeTracker *changeTracker
-
-	priorityCond *sync.Cond
-	priority     int
 }
 
 type LevelDBSession struct {
@@ -75,7 +71,6 @@ func NewLeveDBBackend(
 		encoder:       encoder,
 		decoder:       decoder,
 		changeTracker: changeTracker,
-		priorityCond:  sync.NewCond(new(sync.Mutex)),
 	}
 
 	if !interleaved {
@@ -88,28 +83,6 @@ func NewLeveDBBackend(
 	return
 }
 
-func (ldb *LevelDBBackend) suspend() {
-	ldb.priorityCond.L.Lock()
-	for ldb.priority > 0 {
-		ldb.priorityCond.Wait()
-	}
-	ldb.priorityCond.L.Unlock()
-}
-
-func (ldb *LevelDBBackend) grab() {
-	ldb.priorityCond.L.Lock()
-	ldb.priority++
-	ldb.priorityCond.L.Unlock()
-}
-
-func (ldb *LevelDBBackend) ungrab() {
-	ldb.priorityCond.L.Lock()
-	if ldb.priority--; ldb.priority <= 0 {
-		ldb.priorityCond.Broadcast()
-	}
-	ldb.priorityCond.L.Unlock()
-}
-
 func (ldb *LevelDBBackend) buildCoverage() error {
 	log.Println("INFO: Start building coverage index (this may take some time)...")
 
@@ -180,8 +153,6 @@ func (ldbs *LevelDBSession) Fetch(hash, key []byte) (value []byte, err error) {
 	if key, err = ldbs.backend.decoder(key); err != nil {
 		return
 	}
-	ldbs.backend.grab()
-	defer ldbs.backend.ungrab()
 	ro := leveldb.NewReadOptions()
 	value, err = ldbs.backend.db.Get(ro, key)
 	//if err != nil {
@@ -213,8 +184,6 @@ func (ldbs *LevelDBSession) Store(hash, key, value []byte) (exists bool, err err
 	if key, err = ldbs.backend.decoder(key); err != nil {
 		return
 	}
-	ldbs.backend.grab()
-	defer ldbs.backend.ungrab()
 	if exists, err = keyExists(ldbs.backend.db, key); err != nil {
 		return
 	}
@@ -356,7 +325,6 @@ func (ldbs *LevelDBSession) plainSpatialQuery(
 		for _, r := range ldbs.backend.coverage.Query(c1, c2) {
 			a.Z, b.Z = int16(r.Z), int16(r.Z)
 			a.X, b.X = int16(r.X1), int16(r.X2)
-			ldbs.backend.suspend()
 			for a.Y = r.Y2; a.Y >= r.Y1; a.Y-- {
 				b.Y = a.Y
 				// The keys in the database are stored and ordered as strings
@@ -447,7 +415,6 @@ func (ldbs *LevelDBSession) interleavedSpatialQuery(
 				it.Next()
 			} else {
 				next := common.BigMin(zmin, zmax, zcode)
-				ldbs.backend.suspend()
 				//log.Printf("seeking to: %d\n", next)
 				it.Seek(common.ToBigEndian(next))
 				//log.Printf("seeking done: %d\n", next)