prysm-pulse/beacon-chain/state/stateutil/field_root_validator.go
Potuz f97db3b738
Different parallel hashing (#12639)
* Paralellize hashing of large lists

* add unit test

* add file

* do not parallelize on low processor count

* revert minimal proc count

---------

Co-authored-by: Nishant Das <nishdas93@gmail.com>
2023-07-21 20:36:20 -04:00

108 lines
3.4 KiB
Go

package stateutil
import (
"bytes"
"encoding/binary"
"runtime"
"sync"
"github.com/pkg/errors"
fieldparams "github.com/prysmaticlabs/prysm/v4/config/fieldparams"
"github.com/prysmaticlabs/prysm/v4/crypto/hash/htr"
"github.com/prysmaticlabs/prysm/v4/encoding/ssz"
ethpb "github.com/prysmaticlabs/prysm/v4/proto/prysm/v1alpha1"
"github.com/sirupsen/logrus"
)
const (
// number of field roots for the validator object.
validatorFieldRoots = 8
// Depth of tree representation of an individual
// validator.
// NumOfRoots = 2 ^ (TreeDepth)
// 8 = 2 ^ 3
validatorTreeDepth = 3
)
// ValidatorRegistryRoot computes the HashTreeRoot Merkleization of
// a list of validator structs according to the Ethereum
// Simple Serialize specification.
func ValidatorRegistryRoot(vals []*ethpb.Validator) ([32]byte, error) {
return validatorRegistryRoot(vals)
}
func validatorRegistryRoot(validators []*ethpb.Validator) ([32]byte, error) {
roots, err := OptimizedValidatorRoots(validators)
if err != nil {
return [32]byte{}, err
}
validatorsRootsRoot, err := ssz.BitwiseMerkleize(roots, uint64(len(roots)), fieldparams.ValidatorRegistryLimit)
if err != nil {
return [32]byte{}, errors.Wrap(err, "could not compute validator registry merkleization")
}
validatorsRootsBuf := new(bytes.Buffer)
if err := binary.Write(validatorsRootsBuf, binary.LittleEndian, uint64(len(validators))); err != nil {
return [32]byte{}, errors.Wrap(err, "could not marshal validator registry length")
}
// We need to mix in the length of the slice.
var validatorsRootsBufRoot [32]byte
copy(validatorsRootsBufRoot[:], validatorsRootsBuf.Bytes())
res := ssz.MixInLength(validatorsRootsRoot, validatorsRootsBufRoot[:])
return res, nil
}
func hashValidatorHelper(validators []*ethpb.Validator, roots [][32]byte, j int, groupSize int, wg *sync.WaitGroup) {
defer wg.Done()
for i := 0; i < groupSize; i++ {
fRoots, err := ValidatorFieldRoots(validators[j*groupSize+i])
if err != nil {
logrus.WithError(err).Error("could not get validator field roots")
return
}
for k, root := range fRoots {
roots[(j*groupSize+i)*validatorFieldRoots+k] = root
}
}
}
// OptimizedValidatorRoots uses an optimized routine with gohashtree in order to
// derive a list of validator roots from a list of validator objects.
func OptimizedValidatorRoots(validators []*ethpb.Validator) ([][32]byte, error) {
// Exit early if no validators are provided.
if len(validators) == 0 {
return [][32]byte{}, nil
}
wg := sync.WaitGroup{}
n := runtime.GOMAXPROCS(0)
rootsSize := len(validators) * validatorFieldRoots
groupSize := len(validators) / n
roots := make([][32]byte, rootsSize)
wg.Add(n - 1)
for j := 0; j < n-1; j++ {
go hashValidatorHelper(validators, roots, j, groupSize, &wg)
}
for i := (n - 1) * groupSize; i < len(validators); i++ {
fRoots, err := ValidatorFieldRoots(validators[i])
if err != nil {
return [][32]byte{}, errors.Wrap(err, "could not compute validators merkleization")
}
for k, root := range fRoots {
roots[i*validatorFieldRoots+k] = root
}
}
wg.Wait()
// A validator's tree can represented with a depth of 3. As log2(8) = 3
// Using this property we can lay out all the individual fields of a
// validator and hash them in single level using our vectorized routine.
for i := 0; i < validatorTreeDepth; i++ {
// Overwrite input lists as we are hashing by level
// and only need the highest level to proceed.
roots = htr.VectorizedSha256(roots)
}
return roots, nil
}