feat(flags): [Breaking] Add cache superflag for alpha (#7652)

This change introduces cache as a superflag, with size-mb and percentage as subflags for dgraph alphas.
hypermodeinc · Apr 1, 2021 · 32f1f58 · 32f1f58
1 parent 4f8db71
commit 32f1f58
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Showing 6 changed files with 21 additions and 23 deletions.
diff --git a/dgraph/cmd/alpha/admin.go b/dgraph/cmd/alpha/admin.go
@@ -222,7 +222,7 @@ func memoryLimitPutHandler(w http.ResponseWriter, r *http.Request) {
 	}
 	gqlReq := &schema.Request{
 		Query: `
-		mutation config($cacheMb: Int) {
+		mutation config($cacheMb: Float) {
 		  config(input: {cacheMb: $cacheMb}) {
 			response {
 			  code

diff --git a/dgraph/cmd/alpha/run.go b/dgraph/cmd/alpha/run.go
@@ -108,10 +108,6 @@ they form a Raft group and provide synchronous replication.
 	// --encryption_key_file
 	enc.RegisterFlags(flag)
 
-	flag.String("cache_percentage", "0,65,35,0",
-		`Cache percentages summing up to 100 for various caches (FORMAT: PostingListCache,`+
-			`PstoreBlockCache,PstoreIndexCache,WAL).`)
-
 	flag.StringP("postings", "p", "p", "Directory to store posting lists.")
 	flag.String("tmp", "t", "Directory to store temporary buffers.")
 
@@ -149,6 +145,16 @@ they form a Raft group and provide synchronous replication.
 				"worker in a failed state. Use -1 to retry infinitely.").
 		String())
 
+	// Cache flags.
+	flag.String("cache", worker.CacheDefaults, z.NewSuperFlagHelp(worker.CacheDefaults).
+		Head("Cache options").
+		Flag("size-mb",
+			"Total size of cache (in MB) to be used in Dgraph.").
+		Flag("percentage",
+			"Cache percentages summing up to 100 for various caches (FORMAT: PostingListCache,"+
+				"PstoreBlockCache,PstoreIndexCache)").
+		String())
+
 	flag.String("raft", worker.RaftDefaults, z.NewSuperFlagHelp(worker.RaftDefaults).
 		Head("Raft options").
 		Flag("idx",
@@ -618,23 +624,17 @@ func run() {
 	}
 
 	bindall = Alpha.Conf.GetBool("bindall")
-
-	totalCache := int64(Alpha.Conf.GetInt("cache_mb"))
+	cache := z.NewSuperFlag(Alpha.Conf.GetString("cache")).MergeAndCheckDefault(
+		worker.CacheDefaults)
+	totalCache := cache.GetInt64("size-mb")
 	x.AssertTruef(totalCache >= 0, "ERROR: Cache size must be non-negative")
-	if Alpha.Conf.IsSet("lru_mb") {
-		glog.Warningln("--lru_mb is deprecated, use --cache_mb instead")
-		if !Alpha.Conf.IsSet("cache_mb") {
-			totalCache = int64(Alpha.Conf.GetFloat64("lru_mb"))
-		}
-	}
 
-	cachePercentage := Alpha.Conf.GetString("cache_percentage")
-	cachePercent, err := x.GetCachePercentages(cachePercentage, 4)
+	cachePercentage := cache.GetString("percentage")
+	cachePercent, err := x.GetCachePercentages(cachePercentage, 3)
 	x.Check(err)
 	postingListCacheSize := (cachePercent[0] * (totalCache << 20)) / 100
 	pstoreBlockCacheSize := (cachePercent[1] * (totalCache << 20)) / 100
 	pstoreIndexCacheSize := (cachePercent[2] * (totalCache << 20)) / 100
-	walCache := (cachePercent[3] * (totalCache << 20)) / 100
 
 	badger := z.NewSuperFlag(Alpha.Conf.GetString("badger")).MergeAndCheckDefault(
 		worker.BadgerDefaults)
@@ -648,10 +648,10 @@ func run() {
 		WALDir:                     Alpha.Conf.GetString("wal"),
 		PostingDirCompression:      ctype,
 		PostingDirCompressionLevel: clevel,
+		CacheMb:                    totalCache,
 		CachePercentage:            cachePercentage,
 		PBlockCacheSize:            pstoreBlockCacheSize,
 		PIndexCacheSize:            pstoreIndexCacheSize,
-		WalCache:                   walCache,
 
 		MutationsMode:  worker.AllowMutations,
 		AuthToken:      security.GetString("token"),

diff --git a/worker/config.go b/worker/config.go
@@ -54,8 +54,6 @@ type Options struct {
 	PBlockCacheSize int64
 	// PIndexCacheSize is the size of index cache for pstore
 	PIndexCacheSize int64
-	// WalCache is the size of block cache for wstore
-	WalCache int64
 
 	// HmacSecret stores the secret used to sign JSON Web Tokens (JWT).
 	HmacSecret x.SensitiveByteSlice

diff --git a/worker/server_state.go b/worker/server_state.go
@@ -52,6 +52,7 @@ const (
 	ZeroLimitsDefaults = `uid-lease=0; refill-interval=30s`
 	GraphQLDefaults    = `introspection=true; debug=false; extensions=true; poll-interval=1s; ` +
 		`lambda-url=;`
+	CacheDefaults = `size-mb=1024; percentage=0,65,35;`
 )
 
 // ServerState holds the state of the Dgraph server.

diff --git a/worker/worker.go b/worker/worker.go
@@ -149,7 +149,7 @@ func UpdateCacheMb(memoryMB int64) error {
 		return errors.Errorf("cache_mb must be non-negative")
 	}
 
-	cachePercent, err := x.GetCachePercentages(Config.CachePercentage, 4)
+	cachePercent, err := x.GetCachePercentages(Config.CachePercentage, 3)
 	if err != nil {
 		return err
 	}
@@ -164,6 +164,8 @@ func UpdateCacheMb(memoryMB int64) error {
 	if _, err := pstore.CacheMaxCost(badger.IndexCache, indexCacheSize); err != nil {
 		return errors.Wrapf(err, "cannot update index cache size")
 	}
+
+	Config.CacheMb = memoryMB
 	return nil
 }
 

diff --git a/x/flags.go b/x/flags.go
@@ -54,9 +54,6 @@ func FillCommonFlags(flag *pflag.FlagSet) {
 			`guaranteeing no data loss in case of hard reboot.`+"\n    "+
 			`Most users should be OK with choosing "process".`)
 
-	// Cache flags.
-	flag.Int64("cache_mb", 1024, "Total size of cache (in MB) to be used in Dgraph.")
-
 	flag.String("telemetry", TelemetryDefaults, z.NewSuperFlagHelp(TelemetryDefaults).
 		Head("Telemetry (diagnostic) options").
 		Flag("reports",