TransientStorageLib usage

[BZAghalarov]

Hi,

There are some functions use TransientStorageLib's tstore, tload functions.
What is the advantage of these functions over the classical methods ?

For example rather than saving temporary value we can set permanent value and read it from memory.

protocol/src/core/spoke/BalanceSheet.sol

Lines 263 to 270 in 88ccb68

	function overridePricePoolPerAsset(PoolId poolId, ShareClassId scId, AssetId assetId, D18 value)
	external
	payable
	isManager(poolId)
	{
	TransientStorageLib.tstore(keccak256(abi.encode("pricePoolPerAsset", poolId, scId, assetId)), value.raw());
	TransientStorageLib.tstore(keccak256(abi.encode("pricePoolPerAssetIsSet", poolId, scId, assetId)), true);
	}

[lemunozm]

Hi @BZAghalarov, the big difference is gas saving. We just store the value for the transaction, which is much more efficient than storing the value onchain.

Downside is that the value is reset after the transaction, but in these scenarios this is just what we want.