go/oasis-node/cmd/debug/consim: Add --consim.memdb

While it's possible to use the pruner to try to prevent the ABCI induced
disk usage from growing out of control, having to save/prune is rather
slow, even when backed by tmpfs.

Enabling this option will keep ABCI state in memory, dramatically
speeding up cases where only the final dump is required, especially if
a sensible configuration is used for the pruner.

go/consensus/tendermint/abci/mux.go

@@ -67,6 +67,9 @@ type ApplicationConfig struct {
 
 	// OwnTxSigner is the transaction signer identity of the local node.
 	OwnTxSigner signature.PublicKey
+
+	// TestingMemDB forces the MemDB to be used for the state storage.
+	TestingMemDB bool
 }
 
 // TransactionAuthHandler is the interface for ABCI applications that handle

go/consensus/tendermint/abci/state.go

@@ -429,8 +429,15 @@ func (s *applicationState) metricsWorker() {
 	}
 }
 
+func newStateDB(cfg *ApplicationConfig) (dbm.DB, error) {
+	if cfg.TestingMemDB {
+		return dbm.NewMemDB(), nil
+	}
+	return db.New(filepath.Join(cfg.DataDir, "abci-mux-state"), false)
+}
+
 func newApplicationState(ctx context.Context, cfg *ApplicationConfig) (*applicationState, error) {
-	db, err := db.New(filepath.Join(cfg.DataDir, "abci-mux-state"), false)
+	db, err := newStateDB(cfg)
 	if err != nil {
 		return nil, err
 	}

go/oasis-node/cmd/debug/consim/consim.go

@@ -29,6 +29,7 @@ import (
 
 const (
 	cfgNumKept      = "consim.num_kept"
+	cfgMemDB        = "consim.memdb"
 	cfgWorkload     = "consim.workload"
 	cfgWorkloadSeed = "consim.workload.seed"
 )
@@ -115,6 +116,7 @@ func doRun(cmd *cobra.Command, args []string) error {
 		tmChainID:     tmChainID,
 		txAuthHandler: txAuthApp.(abci.TransactionAuthHandler),
 		numVersions:   viper.GetInt64(cfgNumKept),
+		memDB:         viper.GetBool(cfgMemDB),
 	}
 	mockChain, err := initMockChain(ctx, cfg)
 	if err != nil {
@@ -248,6 +250,7 @@ func Register(parentCmd *cobra.Command) {
 
 func init() {
 	flagsConsim.Int64(cfgNumKept, 0, "number of versions kept (0 = all)")
+	flagsConsim.Bool(cfgMemDB, false, "use memory to store state")
 	flagsConsim.String(cfgWorkload, fileWorkloadName, "workload to execute")
 	flagsConsim.String(cfgWorkloadSeed, "seeeeeeeeeeeeeeeeeeeeeeeeeeeeeed", "DRBG seed for workloads")
 	_ = viper.BindPFlags(flagsConsim)

go/oasis-node/cmd/debug/consim/mockchain.go

@@ -26,6 +26,7 @@ type mockChainCfg struct {
 	tmChainID     string
 	txAuthHandler abci.TransactionAuthHandler
 	numVersions   int64
+	memDB         bool
 }
 
 type mockChain struct {
@@ -158,6 +159,7 @@ func initMockChain(ctx context.Context, cfg *mockChainCfg) (*mockChain, error) {
 		HaltEpochHeight: math.MaxUint64,
 		MinGasPrice:     0, // XXX: Should this be configurable?
 		OwnTxSigner:     localSigner.Public(),
+		TestingMemDB:    cfg.memDB,
 	}
 	if cfg.numVersions > 0 {
 		muxCfg.Pruning.Strategy = abci.PruneKeepN