Update badger to commit 91c31ebe8c22 (#4935)

Important changes
```
 - Changes to overlap check in compaction.
 - Remove 'this entry should've been caught' log.
 - Changes to write stalling on levels 0 and 1.
 - Compression is disabled by default in Badger.
 - Bloom filter caching in a separate ristretto cache.
 - Compression/Encryption in background.
 - Disable cache by default in badger.
```

The following new changes are being added from badger
`git log ab4352b00a17...91c31ebe8c22`

```
91c31eb Disable cache by default (#1257)
eaf64c0 Add separate cache for bloom filters (#1260)
1bcbefc Add BypassDirLock option (#1243)
c6c1e5e Add support for watching nil prefix in subscribe API (#1246)
b13b927 Compress/Encrypt Blocks in the background (#1227)
bdb2b13 fix changelog for v2.0.2 (#1244)
8dbc982 Add Dkron to README (#1241)
3d95b94 Remove coveralls from Travis Build(#1219)
5b4c0a6 Fix ValueThreshold for in-memory mode (#1235)
617ed7c Initialize vlog before starting compactions in db.Open (#1226)
e908818 Update CHANGELOG for Badger 2.0.2 release. (#1230)
bce069c Fix int overflow for 32bit (#1216)
e029e93 Remove ExampleDB_Subscribe Test (#1214)
8734e3a Add missing package to README for badger.NewEntry (#1223)
78d405a Replace t.Fatal with require.NoError in tests (#1213)
c51748e Fix flaky TestPageBufferReader2 test (#1210)
eee1602 Change else-if statements to idiomatic switch statements. (#1207)
3e25d77 Rework concurrency semantics of valueLog.maxFid (#1184) (#1187)
4676ca9 Add support for caching bloomfilters (#1204)
c3333a5 Disable compression and set ZSTD Compression Level to 1 (#1191)
0acb3f6 Fix L0/L1 stall test (#1201)
7e5a956 Support disabling the cache completely. (#1183) (#1185)
82381ac Update ristretto to version  8f368f2 (#1195)
3747be5 Improve write stalling on level 0 and 1
5870b7b Run all tests on CI (#1189)
01a00cb Add Jaegar to list of projects (#1192)
9d6512b Use fastRand instead of locked-rand in skiplist (#1173)
2698bfc Avoid sync in inmemory mode (#1190)
2a90c66 Remove the 'this entry should've caught' log from value.go (#1170)
0a06173 Fix checkOverlap in compaction (#1166)
0f2e629 Fix windows build (#1177)
03af216 Fix commit sha for WithInMemory in CHANGELOG. (#1172)
23a73cd Update CHANGELOG for v2.0.1 release. (#1181)
465f28a Cast sz to uint32 to fix compilation on 32 bit (#1175)
ea01d38 Rename option builder from WithInmemory to WithInMemory. (#1169)
df99253 Remove ErrGCInMemoryMode in CHANGELOG. (#1171)
8dfdd6d Adding changes for 2.0.1 so far (#1168)
```

dgraph/cmd/live/run.go

@@ -337,8 +337,10 @@ func setup(opts batchMutationOptions, dc *dgo.Dgraph) *loader {
 		var err error
 		db, err = badger.Open(badger.DefaultOptions(opt.clientDir).
 			WithTableLoadingMode(bopt.MemoryMap).
-			// TODO(Ibrahim): Remove compression level once badger is updated.
-			WithSyncWrites(false).WithZSTDCompressionLevel(1))
+			WithCompression(bopt.ZSTD).
+			WithSyncWrites(false).
+			WithLoadBloomsOnOpen(false).
+			WithZSTDCompressionLevel(3))
 		x.Checkf(err, "Error while creating badger KV posting store")
 
 	}

dgraph/cmd/zero/run.go

@@ -217,10 +217,9 @@ func run() {
 	// Open raft write-ahead log and initialize raft node.
 	x.Checkf(os.MkdirAll(opts.w, 0700), "Error while creating WAL dir.")
 	kvOpt := badger.LSMOnlyOptions(opts.w).WithSyncWrites(false).WithTruncate(true).
-		WithValueLogFileSize(64 << 20).WithMaxCacheSize(10 << 20)
+		WithValueLogFileSize(64 << 20).WithMaxCacheSize(10 << 20).WithLoadBloomsOnOpen(false)
 
-	// TOOD(Ibrahim): Remove this once badger is updated.
-	kvOpt.ZSTDCompressionLevel = 1
+	kvOpt.ZSTDCompressionLevel = 3
 
 	kv, err := badger.Open(kvOpt)
 	x.Checkf(err, "Error while opening WAL store")

go.mod

@@ -16,9 +16,8 @@ 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 v2.0.1-0.20191220102048-ab4352b00a17
+	github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200316175624-91c31ebe8c22
 	github.com/dgraph-io/dgo/v2 v2.2.0
-	github.com/dgraph-io/ristretto v0.0.1 // indirect
 	github.com/dgrijalva/jwt-go v3.2.0+incompatible
 	github.com/dgryski/go-farm v0.0.0-20191112170834-c2139c5d712b
 	github.com/dgryski/go-groupvarint v0.0.0-20190318181831-5ce5df8ca4e1

go.sum

@@ -76,13 +76,12 @@ 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 v2.0.1-0.20191220102048-ab4352b00a17 h1:BxXd8isFVcup+jlLnnEN22xhB+UwLMgAgk56kDxy9AY=
-github.com/dgraph-io/badger/v2 v2.0.1-0.20191220102048-ab4352b00a17/go.mod h1:YoRSIp1LmAJ7zH7tZwRvjNMUYLxB4wl3ebYkaIruZ04=
+github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200316175624-91c31ebe8c22 h1:X2g/STOldw/iNkdP9BHI/8zHe4N/Lkp8Z4jLyywtnCI=
+github.com/dgraph-io/badger/v2 v2.0.1-rc1.0.20200316175624-91c31ebe8c22/go.mod h1:3KY8+bsP8wI0OEnQJAKpd4wIJW/Mm32yw2j/9FUVnIM=
 github.com/dgraph-io/dgo/v2 v2.2.0 h1:qYbm6mEF3wuKiRpgNOldk6PmPbBJFwj6vL7I7dTSdyc=
 github.com/dgraph-io/dgo/v2 v2.2.0/go.mod h1:LJCkLxm5fUMcU+yb8gHFjHt7ChgNuz3YnQQ6MQkmscI=
-github.com/dgraph-io/ristretto v0.0.0-20191025175511-c1f00be0418e/go.mod h1:edzKIzGvqUCMzhTVWbiTSe75zD9Xxq0GtSBtFmaUTZs=
-github.com/dgraph-io/ristretto v0.0.1 h1:cJwdnj42uV8Jg4+KLrYovLiCgIfz9wtWm6E6KA+1tLs=
-github.com/dgraph-io/ristretto v0.0.1/go.mod h1:T40EBc7CJke8TkpiYfGGKAeFjSaxuFXhuXRyumBd6RE=
+github.com/dgraph-io/ristretto v0.0.2-0.20200115201040-8f368f2f2ab3 h1:MQLRM35Pp0yAyBYksjbj1nZI/w6eyRY/mWoM1sFf4kU=
+github.com/dgraph-io/ristretto v0.0.2-0.20200115201040-8f368f2f2ab3/go.mod h1:KPxhHT9ZxKefz+PCeOGsrHpl1qZ7i70dGTu2u+Ahh6E=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible h1:7qlOGliEKZXTDg6OTjfoBKDXWrumCAMpl/TFQ4/5kLM=
 github.com/dgrijalva/jwt-go v3.2.0+incompatible/go.mod h1:E3ru+11k8xSBh+hMPgOLZmtrrCbhqsmaPHjLKYnJCaQ=
 github.com/dgryski/go-farm v0.0.0-20190423205320-6a90982ecee2/go.mod h1:SqUrOPUnsFjfmXRMNPybcSiG0BgUW2AuFH8PAnS2iTw=

worker/server_state.go

@@ -131,8 +131,9 @@ func (s *ServerState) initStorage() {
 		glog.Infof("Opening write-ahead log BadgerDB with options: %+v\n", opt)
 		opt.EncryptionKey = key
 
-		// TODO(Ibrahim): Remove this once badger is updated.
-		opt.ZSTDCompressionLevel = 1
+		opt.ZSTDCompressionLevel = 3
+		opt.Compression = options.ZSTD
+		opt.LoadBloomsOnOpen = false
 
 		s.WALstore, err = badger.Open(opt)
 		x.Checkf(err, "Error while creating badger KV WAL store")
@@ -153,6 +154,10 @@ func (s *ServerState) initStorage() {
 		glog.Infof("Opening postings BadgerDB with options: %+v\n", opt)
 		opt.EncryptionKey = key
 
+		opt.Compression = options.ZSTD
+		opt.ZSTDCompressionLevel = 3
+		opt.LoadBloomsOnOpen = false
+
 		s.Pstore, err = badger.OpenManaged(opt)
 		x.Checkf(err, "Error while creating badger KV posting store")