feat(Dgraph): Add ability to change size of caches through the admin …

…interface. (#6644)

The endpoints have been changed from lruMb to cacheMb to reflect that this
is changing the value of the cacheMb flag.

Fixes DGRAPH-2515

dgraph/cmd/alpha/admin.go

@@ -172,14 +172,14 @@ func memoryLimitPutHandler(w http.ResponseWriter, r *http.Request, adminServer w
 	}
 	gqlReq := &schema.Request{
 		Query: `
-		mutation config($lruMb: Float) {
-		  config(input: {lruMb: $lruMb}) {
+		mutation config($cacheMb: Int) {
+		  config(input: {cacheMb: $cacheMb}) {
 			response {
 			  code
 			}
 		  }
 		}`,
-		Variables: map[string]interface{}{"lruMb": memoryMB},
+		Variables: map[string]interface{}{"cacheMb": memoryMB},
 	}
 	resp := resolveWithAdminServer(gqlReq, r, adminServer)
 
@@ -196,19 +196,19 @@ func memoryLimitGetHandler(w http.ResponseWriter, r *http.Request, adminServer w
 		Query: `
 		query {
 		  config {
-			lruMb
+			cacheMb
 		  }
 		}`,
 	}
 	resp := resolveWithAdminServer(gqlReq, r, adminServer)
 	var data struct {
 		Config struct {
-			LruMb float64
+			CacheMb float64
 		}
 	}
 	x.Check(json.Unmarshal(resp.Data.Bytes(), &data))
 
-	if _, err := fmt.Fprintln(w, data.Config.LruMb); err != nil {
+	if _, err := fmt.Fprintln(w, data.Config.CacheMb); err != nil {
 		http.Error(w, err.Error(), http.StatusInternalServerError)
 	}
 }

dgraph/cmd/alpha/run.go

@@ -529,7 +529,7 @@ func setupServer(closer *z.Closer) {
 			exportHandler(w, r, adminServer)
 		}))))
 
-	http.Handle("/admin/config/lru_mb", allowedMethodsHandler(allowedMethods{
+	http.Handle("/admin/config/cache_mb", allowedMethodsHandler(allowedMethods{
 		http.MethodGet: true,
 		http.MethodPut: true,
 	}, adminAuthHandler(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
@@ -605,6 +605,7 @@ func run() {
 		WALDir:                     Alpha.Conf.GetString("wal"),
 		PostingDirCompression:      ctype,
 		PostingDirCompressionLevel: clevel,
+		CachePercentage:            cachePercentage,
 		PBlockCacheSize:            pstoreBlockCacheSize,
 		PIndexCacheSize:            pstoreIndexCacheSize,
 		WalCache:                   walCache,

ee/acl/acl_test.go

@@ -2587,7 +2587,7 @@ func TestGuardianOnlyAccessForAdminEndpoints(t *testing.T) {
 			name: "config update has guardian auth",
 			query: `
 					mutation {
-					  config(input: {lruMb: 1}) {
+					  config(input: {cacheMb: -1}) {
 						response {
 						  code
 						  message
@@ -2597,7 +2597,7 @@ func TestGuardianOnlyAccessForAdminEndpoints(t *testing.T) {
 			queryName:          "config",
 			testGuardianAccess: true,
 			guardianErrs: x.GqlErrorList{{
-				Message:   "resolving config failed because lru_mb must be at least 1024\n",
+				Message:   "resolving config failed because cache_mb must be non-negative",
 				Locations: []x.Location{{Line: 3, Column: 8}},
 			}},
 			guardianData: `{"config": null}`,
@@ -2607,7 +2607,7 @@ func TestGuardianOnlyAccessForAdminEndpoints(t *testing.T) {
 			query: `
 					query {
 					  config {
-						lruMb
+						cacheMb
 					  }
 					}`,
 			queryName:          "config",

go.mod

@@ -19,10 +19,10 @@ require (
 	github.com/blevesearch/segment v0.0.0-20160915185041-762005e7a34f // indirect
 	github.com/blevesearch/snowballstem v0.0.0-20180110192139-26b06a2c243d // indirect
 	github.com/codahale/hdrhistogram v0.0.0-20161010025455-3a0bb77429bd
-	github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20201007014141-e3a0d29f75d9
+	github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20201007220711-3b5f17cee813
 	github.com/dgraph-io/dgo/v200 v200.0.0-20200805103119-a3544c464dd6
 	github.com/dgraph-io/graphql-transport-ws v0.0.0-20200916064635-48589439591b
-	github.com/dgraph-io/ristretto v0.0.4-0.20201012160933-079c5f0d0daf
+	github.com/dgraph-io/ristretto v0.0.4-0.20201007164332-9739cfa2564b
 	github.com/dgrijalva/jwt-go v3.2.0+incompatible
 	github.com/dgrijalva/jwt-go/v4 v4.0.0-preview1
 	github.com/dgryski/go-farm v0.0.0-20200201041132-a6ae2369ad13

go.sum

@@ -84,12 +84,14 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/dgraph-io/badger v1.6.0 h1:DshxFxZWXUcO0xX476VJC07Xsr6ZCBVRHKZ93Oh7Evo=
 github.com/dgraph-io/badger v1.6.0/go.mod h1:zwt7syl517jmP8s94KqSxTlM6IMsdhYy6psNgSztDR4=
-github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20201007014141-e3a0d29f75d9 h1:jcCG8IgceDFY0eigR/Zp2NwRYowQAVYRkVnmBPJEw+0=
-github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20201007014141-e3a0d29f75d9/go.mod h1:KGLxSlEzmRl4n00ZXty5ibkBgDNbFJkHfjkn3Do0o6I=
+github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20201007220711-3b5f17cee813 h1:dYBCsSAR7oRPg18vdLWWwtOg9ojObRRfRXQbkZrx7aE=
+github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20201007220711-3b5f17cee813/go.mod h1:jXV6noHsSocvT3cCY1V91XESeerqGagWUtIttgdo0Lg=
 github.com/dgraph-io/dgo/v200 v200.0.0-20200805103119-a3544c464dd6 h1:toHzMCdCUgYsjM0cW9+wafnKFXfp1HizIJUyzihN+vk=
 github.com/dgraph-io/dgo/v200 v200.0.0-20200805103119-a3544c464dd6/go.mod h1:rHa+h3kI4M8ASOirxyIyNeXBfHFgeskVUum2OrDMN3U=
 github.com/dgraph-io/graphql-transport-ws v0.0.0-20200916064635-48589439591b h1:PDEhlwHpkEQ5WBfOOKZCNZTXFDGyCEWTYDhxGQbyIpk=
 github.com/dgraph-io/graphql-transport-ws v0.0.0-20200916064635-48589439591b/go.mod h1:7z3c/5w0sMYYZF5bHsrh8IH4fKwG5O5Y70cPH1ZLLRQ=
+github.com/dgraph-io/ristretto v0.0.4-0.20201007164332-9739cfa2564b h1:CfEwAh85rqfhhE/DrDCbFdcwVpZ8ESnFRhLatiKdDYM=
+github.com/dgraph-io/ristretto v0.0.4-0.20201007164332-9739cfa2564b/go.mod h1:bDI4cDaalvYSji3vBVDKrn9ouDZrwN974u8ZO/AhYXs=
 github.com/dgraph-io/ristretto v0.0.4-0.20201012160933-079c5f0d0daf h1:FccUHvo6MMTYz+SrPSjgFuwp7W2376H34YVSzm8qjUY=
 github.com/dgraph-io/ristretto v0.0.4-0.20201012160933-079c5f0d0daf/go.mod h1:bDI4cDaalvYSji3vBVDKrn9ouDZrwN974u8ZO/AhYXs=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=

graphql/admin/admin.go

@@ -249,12 +249,12 @@ const (
 	}
 
 	input ConfigInput {
-
 		"""
-		Estimated memory the LRU cache can take. Actual usage by the process would be
-		more than specified here. (default -1 means no set limit)
+		Estimated memory the caches can take. Actual usage by the process would be
+		more than specified here. The caches will be updated according to the
+		cache_percentage flag.
 		"""
-		lruMb: Float
+		cacheMb: Float
 
 		"""
 		True value of logRequest enables logging of all the requests coming to alphas.
@@ -268,7 +268,7 @@ const (
 	}
 
 	type Config {
-		lruMb: Float
+		cacheMb: Float
 	}
 
 	` + adminTypes + `

graphql/admin/config.go

@@ -22,13 +22,12 @@ import (
 
 	"github.com/dgraph-io/dgraph/graphql/resolve"
 	"github.com/dgraph-io/dgraph/graphql/schema"
-	"github.com/dgraph-io/dgraph/posting"
 	"github.com/dgraph-io/dgraph/worker"
 	"github.com/golang/glog"
 )
 
 type configInput struct {
-	LruMB float64
+	CacheMb float64
 	// LogRequest is used to update WorkerOptions.LogRequest. true value of LogRequest enables
 	// logging of all requests coming to alphas. LogRequest type has been kept as *bool instead of
 	// bool to avoid updating WorkerOptions.LogRequest when it has default value of false.
@@ -43,10 +42,8 @@ func resolveUpdateConfig(ctx context.Context, m schema.Mutation) (*resolve.Resol
 		return resolve.EmptyResult(m, err), false
 	}
 
-	if input.LruMB > 0 {
-		if err = worker.UpdateLruMb(input.LruMB); err != nil {
-			return resolve.EmptyResult(m, err), false
-		}
+	if err = worker.UpdateCacheMb(int64(input.CacheMb)); err != nil {
+		return resolve.EmptyResult(m, err), false
 	}
 
 	// input.LogRequest will be nil, when it is not specified explicitly in config request.
@@ -64,9 +61,7 @@ func resolveGetConfig(ctx context.Context, q schema.Query) *resolve.Resolved {
 	glog.Info("Got config query through GraphQL admin API")
 
 	conf := make(map[string]interface{})
-	posting.Config.Lock()
-	conf["lruMb"] = posting.Config.AllottedMemory
-	posting.Config.Unlock()
+	conf["cacheMb"] = float64(worker.Config.CacheMb)
 
 	return &resolve.Resolved{
 		Data:  map[string]interface{}{q.Name(): conf},

graphql/e2e/directives/docker-compose.yml

@@ -86,4 +86,4 @@ services:
       - type: bind
         source: ./script.js
         target: /app/script.js
-        read_only: true
+        read_only: true

posting/config.go

@@ -21,7 +21,6 @@ import "sync"
 // Options contains options for the postings package.
 type Options struct {
 	sync.Mutex
-	AllottedMemory float64
 
 	CommitFraction float64
 }

posting/list_test.go

@@ -1340,7 +1340,6 @@ var ps *badger.DB
 
 func TestMain(m *testing.M) {
 	x.Init()
-	Config.AllottedMemory = 1024.0
 	Config.CommitFraction = 0.10
 
 	dir, err := ioutil.TempDir("", "storetest_")

posting/lists.go

@@ -170,6 +170,10 @@ func Init(ps *badger.DB, cacheSize int64) {
 	}()
 }
 
+func UpdateMaxCost(maxCost int64) {
+	lCache.UpdateMaxCost(maxCost)
+}
+
 // Cleanup waits until the closer has finished processing.
 func Cleanup() {
 	closer.SignalAndWait()

wiki/content/graphql/admin/index.md

@@ -252,12 +252,12 @@ Here are the important types, queries, and mutations from the `admin` schema.
 	}
 
 	input ConfigInput {
-
 		"""
-		Estimated memory the LRU cache can take. Actual usage by the process would be
-		more than specified here. (default -1 means no set limit)
+		Estimated memory the caches can take. Actual usage by the process would be
+		more than specified here. The caches will be updated according to the
+        cache_percentage flag.
 		"""
-		lruMb: Float
+		cacheMb: Float
 
 		"""
 		True value of logRequest enables logging of all the requests coming to alphas.
@@ -271,7 +271,7 @@ Here are the important types, queries, and mutations from the `admin` schema.
 	}
 
 	type Config {
-		lruMb: Float
+		cacheMb: Float
 	}
 
 	type Query {

worker/config.go

@@ -22,7 +22,6 @@ import (
 
 	bo "github.com/dgraph-io/badger/v2/options"
 
-	"github.com/dgraph-io/dgraph/posting"
 	"github.com/dgraph-io/dgraph/x"
 )
 
@@ -66,6 +65,12 @@ type Options struct {
 	AccessJwtTtl time.Duration
 	// RefreshJwtTtl is the TTL of the refresh JWT.
 	RefreshJwtTtl time.Duration
+
+	// CachePercentage is the comma-separated list of cache percentages
+	// used to split the total cache size among the multiple caches.
+	CachePercentage string
+	// CacheMb is the total memory allocated between all the caches.
+	CacheMb int64
 }
 
 // Config holds an instance of the server options..
@@ -78,14 +83,8 @@ func SetConfiguration(newConfig *Options) {
 	}
 	newConfig.validate()
 	Config = *newConfig
-
-	posting.Config.Lock()
-	defer posting.Config.Unlock()
 }
 
-// MinAllottedMemory is the minimum amount of memory needed for the LRU cache.
-const MinAllottedMemory = 1024.0
-
 // AvailableMemory is the total size of the memory we were able to identify.
 var AvailableMemory int64
 

worker/worker.go

@@ -126,15 +126,28 @@ func BlockingStop() {
 	workerServer.Stop()
 }
 
-// UpdateLruMb updates the value of lru_mb
-func UpdateLruMb(memoryMB float64) error {
-	if memoryMB < MinAllottedMemory {
-		return errors.Errorf("lru_mb must be at least %.0f\n", MinAllottedMemory)
+// UpdateCacheMb updates the value of cache_mb and updates the corresponding cache sizes.
+func UpdateCacheMb(memoryMB int64) error {
+	glog.Infof("Updating cacheMb to %d", memoryMB)
+	if memoryMB < 0 {
+		return errors.Errorf("cache_mb must be non-negative")
 	}
 
-	posting.Config.Lock()
-	posting.Config.AllottedMemory = memoryMB
-	posting.Config.Unlock()
+	cachePercent, err := x.GetCachePercentages(Config.CachePercentage, 4)
+	if err != nil {
+		return err
+	}
+	plCacheSize := (cachePercent[0] * (memoryMB << 20)) / 100
+	blockCacheSize := (cachePercent[1] * (memoryMB << 20)) / 100
+	indexCacheSize := (cachePercent[2] * (memoryMB << 20)) / 100
+
+	posting.UpdateMaxCost(plCacheSize)
+	if _, err := pstore.CacheMaxCost(badger.BlockCache, blockCacheSize); err != nil {
+		return errors.Wrapf(err, "cannot update block cache size")
+	}
+	if _, err := pstore.CacheMaxCost(badger.IndexCache, indexCacheSize); err != nil {
+		return errors.Wrapf(err, "cannot update index cache size")
+	}
 	return nil
 }
 

worker/worker_test.go

@@ -362,7 +362,6 @@ func TestProcessTaskIndex(t *testing.T) {
 
 func TestMain(m *testing.M) {
 	x.Init()
-	posting.Config.AllottedMemory = 1024.0
 	posting.Config.CommitFraction = 0.10
 	gr = new(groupi)
 	gr.gid = 1