leaderboard rank cache improvements

CHANGELOG.md

@@ -6,6 +6,7 @@ The format is based on [keep a changelog](http://keepachangelog.com) and this pr
 ## [Unreleased]
 ### Changed
 - Better formatting for graphed values in devconsole status view.
+- Memory usage and population time improvements in leaderboard rank cache.
 
 ### Fixed
 - Correct cursor usage in group listings using only open/closed group state filter.

internal/skiplist/element.go

@@ -13,21 +13,15 @@ type skiplistLevel struct {
 }
 
 type Element struct {
- Value Interface
- backward *Element
- level []*skiplistLevel
+ Value Interface
+ level []*skiplistLevel
 }
 
 // Next returns the next skiplist element or nil.
 func (e *Element) Next() *Element {
  return e.level[0].forward
 }
 
-// Prev returns the previous skiplist element of nil.
-func (e *Element) Prev() *Element {
- return e.backward
-}
-
 // newElement returns an initialized element.
 func newElement(level int, v Interface) *Element {
  slLevels := make([]*skiplistLevel, level)
@@ -36,9 +30,8 @@ func newElement(level int, v Interface) *Element {
  }
 
  return &Element{
- Value: v,
- backward: nil,
- level: slLevels,
+ Value: v,
+ level: slLevels,
  }
 }
 

internal/skiplist/skiplist.go

@@ -9,7 +9,6 @@ type Interface interface {
 type SkipList struct {
  r *rand.Rand
  header *Element
- tail *Element
  update []*Element
  rank []int
  length int
@@ -21,7 +20,6 @@ func New() *SkipList {
  return &SkipList{
  r: rand.New(rand.NewSource(1)),
  header: newElement(SKIPLIST_MAXLEVEL, nil),
- tail: nil,
  update: make([]*Element, SKIPLIST_MAXLEVEL),
  rank: make([]int, SKIPLIST_MAXLEVEL),
  length: 0,
@@ -32,7 +30,6 @@ func New() *SkipList {
 // Init initializes or clears skiplist sl.
 func (sl *SkipList) Init() *SkipList {
  sl.header = newElement(SKIPLIST_MAXLEVEL, nil)
- sl.tail = nil
  sl.update = make([]*Element, SKIPLIST_MAXLEVEL)
  sl.rank = make([]int, SKIPLIST_MAXLEVEL)
  sl.length = 0
@@ -45,11 +42,6 @@ func (sl *SkipList) Front() *Element {
  return sl.header.level[0].forward
 }
 
-// Back returns the last elements of skiplist sl or nil.
-func (sl *SkipList) Back() *Element {
- return sl.tail
-}
-
 // Len returns the numbler of elements of skiplist sl.
 func (sl *SkipList) Len() int {
  return sl.length
@@ -99,16 +91,6 @@ func (sl *SkipList) Insert(v Interface) *Element {
  sl.update[i].level[i].span++
  }
 
- if sl.update[0] == sl.header {
- x.backward = nil
- } else {
- x.backward = sl.update[0]
- }
- if x.level[0].forward != nil {
- x.level[0].forward.backward = x
- } else {
- sl.tail = x
- }
  sl.length++
 
  return x
@@ -125,12 +107,6 @@ func (sl *SkipList) deleteElement(e *Element, update []*Element) {
  }
  }
 
- if e.level[0].forward != nil {
- e.level[0].forward.backward = e.backward
- } else {
- sl.tail = e.backward
- }
-
  for sl.level > 1 && sl.header.level[sl.level-1].forward == nil {
  sl.level--
  }

internal/skiplist/skiplist_test.go

@@ -15,24 +15,24 @@ func (i Int) Less(other interface{}) bool {
 
 func TestInt(t *testing.T) {
  sl := New()
- if sl.Len() != 0 || sl.Front() != nil && sl.Back() != nil {
+ if sl.Len() != 0 || sl.Front() != nil {
  t.Fatal()
  }
 
  testData := []Int{Int(1), Int(2), Int(3)}
 
  sl.Insert(testData[0])
- if sl.Len() != 1 || sl.Front().Value.(Int) != testData[0] || sl.Back().Value.(Int) != testData[0] {
+ if sl.Len() != 1 || sl.Front().Value.(Int) != testData[0] {
  t.Fatal()
  }
 
  sl.Insert(testData[2])
- if sl.Len() != 2 || sl.Front().Value.(Int) != testData[0] || sl.Back().Value.(Int) != testData[2] {
+ if sl.Len() != 2 || sl.Front().Value.(Int) != testData[0] {
  t.Fatal()
  }
 
  sl.Insert(testData[1])
- if sl.Len() != 3 || sl.Front().Value.(Int) != testData[0] || sl.Back().Value.(Int) != testData[2] {
+ if sl.Len() != 3 || sl.Front().Value.(Int) != testData[0] {
  t.Fatal()
  }
 
@@ -74,29 +74,13 @@ func TestInt(t *testing.T) {
  sl.Delete(Int(1000))
 
  expect = []Int{Int(-999), Int(-888), Int(1), Int(3), Int(999)}
- ret = make([]Int, 0)
-
- for e := sl.Back(); e != nil; e = e.Prev() {
- ret = append(ret, e.Value.(Int))
- }
-
- for i := 0; i < len(ret); i++ {
- if ret[i] != expect[len(ret)-i-1] {
- t.Fatal()
- }
- }
 
  if sl.Front().Value.(Int) != -999 {
  t.Fatal()
  }
 
  sl.Remove(sl.Front())
- if sl.Front().Value.(Int) != -888 || sl.Back().Value.(Int) != 999 {
- t.Fatal()
- }
-
- sl.Remove(sl.Back())
- if sl.Front().Value.(Int) != -888 || sl.Back().Value.(Int) != 3 {
+ if sl.Front().Value.(Int) != -888 {
  t.Fatal()
  }
 
@@ -109,7 +93,7 @@ func TestInt(t *testing.T) {
  t.Fatal()
  }
 
- if sl.Len() != 3 {
+ if sl.Len() != 4 {
  t.Fatal()
  }
 
@@ -121,7 +105,7 @@ func TestInt(t *testing.T) {
  t.Fatal()
  }
 
- expect = []Int{Int(2), Int(2), Int(2), Int(3)}
+ expect = []Int{Int(2), Int(2), Int(2), Int(3), Int(999)}
  ret = make([]Int, 0)
  for ; e != nil; e = e.Next() {
  ret = append(ret, e.Value.(Int))
@@ -133,8 +117,8 @@ func TestInt(t *testing.T) {
  }
 
  sl2 := sl.Init()
- if sl.Len() != 0 || sl.Front() != nil || sl.Back() != nil ||
- sl2.Len() != 0 || sl2.Front() != nil || sl2.Back() != nil {
+ if sl.Len() != 0 || sl.Front() != nil ||
+ sl2.Len() != 0 || sl2.Front() != nil {
  t.Fatal()
  }
 

server/api_account.go

@@ -93,7 +93,7 @@ func (s *ApiServer) DeleteAccount(ctx context.Context, in *emptypb.Empty) (*empt
  }
  }
 
- if err := DeleteAccount(ctx, s.logger, s.db, s.config, s.leaderboardRankCache, s.sessionRegistry, s.sessionCache, s.tracker, userID, false); err != nil {
+ if err := DeleteAccount(ctx, s.logger, s.db, s.config, s.leaderboardCache, s.leaderboardRankCache, s.sessionRegistry, s.sessionCache, s.tracker, userID, false); err != nil {
  if err == ErrAccountNotFound {
  return nil, status.Error(codes.NotFound, "Account not found.")
  }

server/api_leaderboard.go

@@ -18,7 +18,6 @@ import (
  "bytes"
  "context"
  "encoding/json"
-
  "github.com/gofrs/uuid"
  "github.com/heroiclabs/nakama-common/api"
  "go.uber.org/zap"