Reduce per tx execution allocations

[benaadams]

Changes

Saves 8.6MB of allocations per min; reduces worse case from smart contracts that do huge amounts of calls

• Reduce allocations by pooling StackAccessTracker collections
• Reduce allocations by pooling EvmState
• EvmState, pass large struct via in
• Change StackAccessTracker and EvmState to file level namespaces
• Rearranged parameters and assignment order to match layout order

EvmState is a super chonky class and currently allocated for every tx and every internal call (and this is after shrinking StackAccessTracker)

Type layout for 'EvmState'
Size: 368 bytes. Paddings: 10 bytes (%2 of empty space)
|==================================================================================|
| Object Header (8 bytes)                                                          |
|----------------------------------------------------------------------------------|
| Method Table Ptr (8 bytes)                                                       |
|==================================================================================|
|   0-7: Byte[] DataStack (8 bytes)                                                |
|----------------------------------------------------------------------------------|
|  8-15: Int32[] ReturnStack (8 bytes)                                             |
|----------------------------------------------------------------------------------|
| 16-23: Int64 <GasAvailable>k__BackingField (8 bytes)                             |
|----------------------------------------------------------------------------------|
| 24-31: Int64 <OutputDestination>k__BackingField (8 bytes)                        |
|----------------------------------------------------------------------------------|
| 32-39: Int64 <OutputLength>k__BackingField (8 bytes)                             |
|----------------------------------------------------------------------------------|
| 40-47: Int64 <Refund>k__BackingField (8 bytes)                                   |
|----------------------------------------------------------------------------------|
| 48-51: Int32 DataStackHead (4 bytes)                                             |
|----------------------------------------------------------------------------------|
| 52-55: Int32 ReturnStackHead (4 bytes)                                           |
|----------------------------------------------------------------------------------|
| 56-59: ExecutionType <ExecutionType>k__BackingField (4 bytes)                    |
| |================================|                                               |
| |   0-3: Int32 value__ (4 bytes) |                                               |
| |================================|                                               |
|----------------------------------------------------------------------------------|
| 60-63: Int32 <ProgramCounter>k__BackingField (4 bytes)                           |
|----------------------------------------------------------------------------------|
|    64: Boolean <IsTopLevel>k__BackingField (1 byte)                              |
|----------------------------------------------------------------------------------|
|    65: Boolean _canRestore (1 byte)                                              |
|----------------------------------------------------------------------------------|
|    66: Boolean <IsStatic>k__BackingField (1 byte)                                |
|----------------------------------------------------------------------------------|
|    67: Boolean <IsContinuation>k__BackingField (1 byte)                          |
|----------------------------------------------------------------------------------|
|    68: Boolean <IsCreateOnPreExistingAccount>k__BackingField (1 byte)            |
|----------------------------------------------------------------------------------|
|    69: Boolean _isDisposed (1 byte)                                              |
|----------------------------------------------------------------------------------|
| 70-71: padding (2 bytes)                                                         |
|----------------------------------------------------------------------------------|
| 72-103: EvmPooledMemory _memory (32 bytes)                                       |
| |=================================================|                              |
| |   0-7: Byte[] _memory (8 bytes)                 |                              |
| |-------------------------------------------------|                              |
| |  8-15: UInt64 _lastZeroedSize (8 bytes)         |                              |
| |-------------------------------------------------|                              |
| | 16-23: UInt64 <Length>k__BackingField (8 bytes) |                              |
| |-------------------------------------------------|                              |
| | 24-31: UInt64 <Size>k__BackingField (8 bytes)   |                              |
| |=================================================|                              |
|----------------------------------------------------------------------------------|
| 104-115: Snapshot <Snapshot>k__BackingField (12 bytes)                           |
| |=======================================================================|        |
| |   0-3: Int32 <StateSnapshot>k__BackingField (4 bytes)                 |        |
| |-----------------------------------------------------------------------|        |
| |  4-11: Storage <StorageSnapshot>k__BackingField (8 bytes)             |        |
| | |===================================================================| |        |
| | |   0-3: Int32 <PersistentStorageSnapshot>k__BackingField (4 bytes) | |        |
| | |-------------------------------------------------------------------| |        |
| | |   4-7: Int32 <TransientStorageSnapshot>k__BackingField (4 bytes)  | |        |
| | |===================================================================| |        |
| |=======================================================================|        |
|----------------------------------------------------------------------------------|
| 116-119: padding (4 bytes)                                                       |
|----------------------------------------------------------------------------------|
| 120-343: ExecutionEnvironment _env (224 bytes)                                   |
| |==============================================================================| |
| |   0-7: CodeInfo CodeInfo (8 bytes)                                           | |
| |------------------------------------------------------------------------------| |
| |  8-15: Address ExecutingAccount (8 bytes)                                    | |
| |------------------------------------------------------------------------------| |
| | 16-23: Address Caller (8 bytes)                                              | |
| |------------------------------------------------------------------------------| |
| | 24-31: Address CodeSource (8 bytes)                                          | |
| |------------------------------------------------------------------------------| |
| | 32-35: Int32 CallDepth (4 bytes)                                             | |
| |------------------------------------------------------------------------------| |
| | 36-39: padding (4 bytes)                                                     | |
| |------------------------------------------------------------------------------| |
| | 40-55: ReadOnlyMemory`1 InputData (16 bytes)                                 | |
| | |=================================|                                          | |
| | |   0-7: Object _object (8 bytes) |                                          | |
| | |---------------------------------|                                          | |
| | |  8-11: Int32 _index (4 bytes)   |                                          | |
| | |---------------------------------|                                          | |
| | | 12-15: Int32 _length (4 bytes)  |                                          | |
| | |=================================|                                          | |
| |------------------------------------------------------------------------------| |
| | 56-159: TxExecutionContext TxExecutionContext (104 bytes)                    | |
| | |==========================================================================| | |
| | |   0-7: Address <Origin>k__BackingField (8 bytes)                         | | |
| | |--------------------------------------------------------------------------| | |
| | |  8-15: Byte[][] <BlobVersionedHashes>k__BackingField (8 bytes)           | | |
| | |--------------------------------------------------------------------------| | |
| | | 16-23: ICodeInfoRepository <CodeInfoRepository>k__BackingField (8 bytes) | | |
| | |--------------------------------------------------------------------------| | |
| | | 24-71: BlockExecutionContext BlockExecutionContext (48 bytes)            | | |
| | | |===========================================================|            | | |
| | | |   0-7: BlockHeader <Header>k__BackingField (8 bytes)      |            | | |
| | | |-----------------------------------------------------------|            | | |
| | | |  8-47: Nullable`1 <BlobBaseFee>k__BackingField (40 bytes) |            | | |
| | | |===========================================================|            | | |
| | |--------------------------------------------------------------------------| | |
| | | 72-103: UInt256 <GasPrice>k__BackingField (32 bytes)                     | | |
| | | |============================|                                           | | |
| | | |   0-7: UInt64 u0 (8 bytes) |                                           | | |
| | | |----------------------------|                                           | | |
| | | |  8-15: UInt64 u1 (8 bytes) |                                           | | |
| | | |----------------------------|                                           | | |
| | | | 16-23: UInt64 u2 (8 bytes) |                                           | | |
| | | |----------------------------|                                           | | |
| | | | 24-31: UInt64 u3 (8 bytes) |                                           | | |
| | | |============================|                                           | | |
| | |==========================================================================| | |
| |------------------------------------------------------------------------------| |
| | 160-191: UInt256 TransferValue (32 bytes)                                    | |
| | |============================|                                               | |
| | |   0-7: UInt64 u0 (8 bytes) |                                               | |
| | |----------------------------|                                               | |
| | |  8-15: UInt64 u1 (8 bytes) |                                               | |
| | |----------------------------|                                               | |
| | | 16-23: UInt64 u2 (8 bytes) |                                               | |
| | |----------------------------|                                               | |
| | | 24-31: UInt64 u3 (8 bytes) |                                               | |
| | |============================|                                               | |
| |------------------------------------------------------------------------------| |
| | 192-223: UInt256 Value (32 bytes)                                            | |
| | |============================|                                               | |
| | |   0-7: UInt64 u0 (8 bytes) |                                               | |
| | |----------------------------|                                               | |
| | |  8-15: UInt64 u1 (8 bytes) |                                               | |
| | |----------------------------|                                               | |
| | | 16-23: UInt64 u2 (8 bytes) |                                               | |
| | |----------------------------|                                               | |
| | | 24-31: UInt64 u3 (8 bytes) |                                               | |
| | |============================|                                               | |
| |==============================================================================| |
|----------------------------------------------------------------------------------|
| 344-367: StackAccessTracker _accessTracker (24 bytes)                            |
| |===============================================|                                |
| |   0-7: TrackingState _trackingState (8 bytes) |                                |
| |-----------------------------------------------|                                |
| |  8-11: Int32 _addressesSnapshots (4 bytes)    |                                |
| |-----------------------------------------------|                                |
| | 12-15: Int32 _storageKeysSnapshots (4 bytes)  |                                |
| |-----------------------------------------------|                                |
| | 16-19: Int32 _destroyListSnapshots (4 bytes)  |                                |
| |-----------------------------------------------|                                |
| | 20-23: Int32 _logsSnapshots (4 bytes)         |                                |
| |===============================================|                                |
|==================================================================================|

Types of changes

What types of changes does your code introduce?

• Optimization

Testing

Requires testing

• No

[LukaszRozmej]

We should return RentFrame too

[benaadams]

We should return RentFrame too

Are returned when the Frames are unwound:

For exception

nethermind/src/Nethermind/Nethermind.Evm/VirtualMachine.cs

Lines 259 to 261 in 5c5c86e

	currentState.Dispose();
	currentState = _stateStack.Pop();
	currentState.IsContinuation = true;

For success:

nethermind/src/Nethermind/Nethermind.Evm/VirtualMachine.cs

Lines 326 to 330 in 5c5c86e

	using (EvmState previousState = currentState)
	{
	currentState = _stateStack.Pop();
	currentState.IsContinuation = true;
	currentState.GasAvailable += previousState.GasAvailable;