From a65f838eb1e6cacf98db2a13ee762221baf93dee Mon Sep 17 00:00:00 2001
From: Albert Chon <albert@injectiveprotocol.com>
Date: Fri, 5 Mar 2021 17:25:19 +0100
Subject: [PATCH] reduce gas costs by 10x for transient store operations
 (#8790)

* reduce gas costs by 10x for transient store operations

* fix TestTransientGasConfig for ReadCostFlat

* added changelog entry

* fix changelog

* fix changelog

Co-authored-by: Alessio Treglia <alessio@tendermint.com>
---
 CHANGELOG.md            |  1 +
 store/types/gas.go      | 11 +++++++++--
 store/types/gas_test.go | 14 +++++++-------
 3 files changed, 17 insertions(+), 9 deletions(-)

diff --git a/CHANGELOG.md b/CHANGELOG.md
index fd2ae140a..972be3a80 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -68,6 +68,7 @@ Ref: https://keepachangelog.com/en/1.0.0/
 * (x/gov) [\#7733](https://github.com/cosmos/cosmos-sdk/pull/7733) ADR 037 Implementation: Governance Split Votes
 * (x/bank) [\#8656](https://github.com/cosmos/cosmos-sdk/pull/8656) balance and supply are now correctly tracked via `coin_spent`, `coin_received`, `coinbase` and `burn` events.
 * (x/bank) [\#8517](https://github.com/cosmos/cosmos-sdk/pull/8517) Supply is now stored and tracked as `sdk.Coins`
+* (store) [\#8790](https://github.com/cosmos/cosmos-sdk/pull/8790) Reduce gas costs by 10x for transient store operations.
 
 ### Improvements
 
diff --git a/store/types/gas.go b/store/types/gas.go
index c6c94f859..028edc350 100644
--- a/store/types/gas.go
+++ b/store/types/gas.go
@@ -176,6 +176,13 @@ func KVGasConfig() GasConfig {
 
 // TransientGasConfig returns a default gas config for TransientStores.
 func TransientGasConfig() GasConfig {
-	// TODO: define gasconfig for transient stores
-	return KVGasConfig()
+	return GasConfig{
+		HasCost:          100,
+		DeleteCost:       100,
+		ReadCostFlat:     100,
+		ReadCostPerByte:  0,
+		WriteCostFlat:    200,
+		WriteCostPerByte: 3,
+		IterNextCostFlat: 3,
+	}
 }
diff --git a/store/types/gas_test.go b/store/types/gas_test.go
index bd62d463c..f44907471 100644
--- a/store/types/gas_test.go
+++ b/store/types/gas_test.go
@@ -93,12 +93,12 @@ func TestTransientGasConfig(t *testing.T) {
 	t.Parallel()
 	config := TransientGasConfig()
 	require.Equal(t, config, GasConfig{
-		HasCost:          1000,
-		DeleteCost:       1000,
-		ReadCostFlat:     1000,
-		ReadCostPerByte:  3,
-		WriteCostFlat:    2000,
-		WriteCostPerByte: 30,
-		IterNextCostFlat: 30,
+		HasCost:          100,
+		DeleteCost:       100,
+		ReadCostFlat:     100,
+		ReadCostPerByte:  0,
+		WriteCostFlat:    200,
+		WriteCostPerByte: 3,
+		IterNextCostFlat: 3,
 	})
 }