prysm-pulse/beacon-chain/state/stategen/service.go
terence tsao f2a3fadda7
Productionization new state service part 1 (#5230)
* Fixed last play methods

* Fixed a regression. Genesis case for state gen

* Comment

* Starting

* Update proto

* Remove boundary root usages

* Update migrate

* Clean up

* Remove unused db methods

* Kafta

* Kafta

* Update tests

* Comments

* Fix state summary tests

* Missed one pass through for kafta
2020-03-27 13:28:38 -07:00

82 lines
2.7 KiB
Go

package stategen
import (
"context"
"sync"
"github.com/prysmaticlabs/prysm/beacon-chain/cache"
"github.com/prysmaticlabs/prysm/beacon-chain/core/helpers"
"github.com/prysmaticlabs/prysm/beacon-chain/db"
"github.com/prysmaticlabs/prysm/beacon-chain/state"
"github.com/prysmaticlabs/prysm/shared/params"
"go.opencensus.io/trace"
)
const archivedInterval = 256
// State represents a management object that handles the internal
// logic of maintaining both hot and cold states in DB.
type State struct {
beaconDB db.NoHeadAccessDatabase
slotsPerArchivedPoint uint64
epochBoundarySlotToRoot map[uint64][32]byte
epochBoundaryLock sync.RWMutex
hotStateCache *cache.HotStateCache
splitInfo *splitSlotAndRoot
}
// This tracks the split point. The point where slot and the block root of
// cold and hot sections of the DB splits.
type splitSlotAndRoot struct {
slot uint64
root [32]byte
}
// New returns a new state management object.
func New(db db.NoHeadAccessDatabase) *State {
return &State{
beaconDB: db,
epochBoundarySlotToRoot: make(map[uint64][32]byte),
hotStateCache: cache.NewHotStateCache(),
splitInfo: &splitSlotAndRoot{slot: 0, root: params.BeaconConfig().ZeroHash},
slotsPerArchivedPoint: archivedInterval,
}
}
// Resume resumes a new state management object from previously saved finalized check point in DB.
func (s *State) Resume(ctx context.Context) (*state.BeaconState, error) {
ctx, span := trace.StartSpan(ctx, "stateGen.Resume")
defer span.End()
lastArchivedRoot := s.beaconDB.LastArchivedIndexRoot(ctx)
lastArchivedState, err := s.beaconDB.State(ctx, lastArchivedRoot)
if err != nil {
return nil, err
}
// Resume as genesis state if there's no last archived state.
if lastArchivedState == nil {
return s.beaconDB.GenesisState(ctx)
}
s.splitInfo = &splitSlotAndRoot{slot: lastArchivedState.Slot(), root: lastArchivedRoot}
// In case the finalized state slot was skipped.
slot := lastArchivedState.Slot()
if !helpers.IsEpochStart(slot) {
slot = helpers.StartSlot(helpers.SlotToEpoch(slot) + 1)
}
return lastArchivedState, nil
}
// This verifies the archive point frequency is valid. It checks the interval
// is a divisor of the number of slots per epoch. This ensures we have at least one
// archive point within range of our state root history when iterating
// backwards. It also ensures the archive points align with hot state summaries
// which makes it quicker to migrate hot to cold.
func verifySlotsPerArchivePoint(slotsPerArchivePoint uint64) bool {
return slotsPerArchivePoint > 0 &&
slotsPerArchivePoint%params.BeaconConfig().SlotsPerEpoch == 0
}