gaspersic/go-ethereum
1
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

[release/1.4.6] eth/downloader: implement concurrent header downloads

Browse Source 
(cherry picked from commit b40dc8a1da)
This commit is contained in:
Péter Szilágyi
2016-02-25 18:36:42 +02:00
parent 5fb29fd45f
commit 7df36e5ec1
4 changed files with 584 additions and 211 deletions
Download Patch File Download Diff File Expand all files Collapse all files

202
eth/downloader/queue.go
View File

@ -39,8 +39,8 @@ import (
)
var (
blockCacheLimit = 8192 // Maximum number of blocks to cache before throttling the download
maxInFlightStates = 4096 // Maximum number of state downloads to allow concurrently
blockCacheLimit = 16384 // Maximum number of blocks to cache before throttling the download
maxInFlightStates = 8192 // Maximum number of state downloads to allow concurrently
)
var (
@ -52,6 +52,7 @@ var (
// fetchRequest is a currently running data retrieval operation.
type fetchRequest struct {
Peer *peer // Peer to which the request was sent
From uint64 // [eth/62] Requested chain element index (used for skeleton fills only)
Hashes map[common.Hash]int // [eth/61] Requested hashes with their insertion index (priority)
Headers []*types.Header // [eth/62] Requested headers, sorted by request order
Time time.Time // Time when the request was made
@ -79,6 +80,17 @@ type queue struct {
headerHead common.Hash // [eth/62] Hash of the last queued header to verify order
// Headers are "special", they download in batches, supported by a skeleton chain
headerTaskPool map[uint64]*types.Header // [eth/62] Pending header retrieval tasks, mapping starting indexes to skeleton headers
headerTaskQueue *prque.Prque // [eth/62] Priority queue of the skeleton indexes to fetch the filling headers for
headerPeerMiss map[string]map[uint64]struct{} // [eth/62] Set of per-peer header batches known to be unavailable
headerPendPool map[string]*fetchRequest // [eth/62] Currently pending header retrieval operations
headerDonePool map[uint64]struct{} // [eth/62] Set of the completed header fetches
headerResults []*types.Header // [eth/62] Result cache accumulating the completed headers
headerOffset uint64 // [eth/62] Number of the first header in the result cache
headerContCh chan bool // [eth/62] Channel to notify when header download finishes
// All data retrievals below are based on an already assembles header chain
blockTaskPool map[common.Hash]*types.Header // [eth/62] Pending block (body) retrieval tasks, mapping hashes to headers
blockTaskQueue *prque.Prque // [eth/62] Priority queue of the headers to fetch the blocks (bodies) for
blockPendPool map[string]*fetchRequest // [eth/62] Currently pending block (body) retrieval operations
@ -113,6 +125,8 @@ func newQueue(stateDb ethdb.Database) *queue {
return &queue{
hashPool: make(map[common.Hash]int),
hashQueue: prque.New(),
headerPendPool: make(map[string]*fetchRequest),
headerContCh: make(chan bool),
blockTaskPool: make(map[common.Hash]*types.Header),
blockTaskQueue: prque.New(),
blockPendPool: make(map[string]*fetchRequest),
@ -149,6 +163,8 @@ func (q *queue) Reset() {
q.headerHead = common.Hash{}
q.headerPendPool = make(map[string]*fetchRequest)
q.blockTaskPool = make(map[common.Hash]*types.Header)
q.blockTaskQueue.Reset()
q.blockPendPool = make(map[string]*fetchRequest)
@ -178,6 +194,14 @@ func (q *queue) Close() {
q.active.Broadcast()
}
// PendingHeaders retrieves the number of header requests pending for retrieval.
func (q *queue) PendingHeaders() int {
q.lock.Lock()
defer q.lock.Unlock()
return q.headerTaskQueue.Size()
}
// PendingBlocks retrieves the number of block (body) requests pending for retrieval.
func (q *queue) PendingBlocks() int {
q.lock.Lock()
@ -205,6 +229,15 @@ func (q *queue) PendingNodeData() int {
return 0
}
// InFlightHeaders retrieves whether there are header fetch requests currently
// in flight.
func (q *queue) InFlightHeaders() bool {
q.lock.Lock()
defer q.lock.Unlock()
return len(q.headerPendPool) > 0
}
// InFlightBlocks retrieves whether there are block fetch requests currently in
// flight.
func (q *queue) InFlightBlocks() bool {
@ -317,6 +350,44 @@ func (q *queue) Schedule61(hashes []common.Hash, fifo bool) []common.Hash {
return inserts
}
// ScheduleSkeleton adds a batch of header retrieval tasks to the queue to fill
// up an already retrieved header skeleton.
func (q *queue) ScheduleSkeleton(from uint64, skeleton []*types.Header) {
q.lock.Lock()
defer q.lock.Unlock()
// No skeleton retrieval can be in progress, fail hard if so (huge implementation bug)
if q.headerResults != nil {
panic("skeleton assembly already in progress")
}
// Shedule all the header retrieval tasks for the skeleton assembly
q.headerTaskPool = make(map[uint64]*types.Header)
q.headerTaskQueue = prque.New()
q.headerPeerMiss = make(map[string]map[uint64]struct{}) // Reset availability to correct invalid chains
q.headerResults = make([]*types.Header, len(skeleton)*MaxHeaderFetch)
q.headerOffset = from
q.headerContCh = make(chan bool, 1)
for i, header := range skeleton {
index := from + uint64(i*MaxHeaderFetch)
q.headerTaskPool[index] = header
q.headerTaskQueue.Push(index, -float32(index))
}
}
// RetrieveHeaders retrieves the header chain assemble based on the scheduled
// skeleton.
func (q *queue) RetrieveHeaders() []*types.Header {
q.lock.Lock()
defer q.lock.Unlock()
headers := q.headerResults
q.headerResults = nil
return headers
}
// Schedule adds a set of headers for the download queue for scheduling, returning
// the new headers encountered.
func (q *queue) Schedule(headers []*types.Header, from uint64) []*types.Header {
@ -437,6 +508,46 @@ func (q *queue) countProcessableItems() int {
return len(q.resultCache)
}
// ReserveHeaders reserves a set of headers for the given peer, skipping any
// previously failed batches.
func (q *queue) ReserveHeaders(p *peer, count int) *fetchRequest {
q.lock.Lock()
defer q.lock.Unlock()
// Short circuit if the peer's already downloading something (sanity check to
// not corrupt state)
if _, ok := q.headerPendPool[p.id]; ok {
return nil
}
// Retrieve a batch of hashes, skipping previously failed ones
send, skip := uint64(0), []uint64{}
for send == 0 && !q.headerTaskQueue.Empty() {
from, _ := q.headerTaskQueue.Pop()
if q.headerPeerMiss[p.id] != nil {
if _, ok := q.headerPeerMiss[p.id][from.(uint64)]; ok {
skip = append(skip, from.(uint64))
continue
}
}
send = from.(uint64)
}
// Merge all the skipped batches back
for _, from := range skip {
q.headerTaskQueue.Push(from, -float32(from))
}
// Assemble and return the block download request
if send == 0 {
return nil
}
request := &fetchRequest{
Peer: p,
From: send,
Time: time.Now(),
}
q.headerPendPool[p.id] = request
return request
}
// ReserveBlocks reserves a set of block hashes for the given peer, skipping any
// previously failed download.
func (q *queue) ReserveBlocks(p *peer, count int) *fetchRequest {
@ -635,6 +746,11 @@ func (q *queue) reserveHeaders(p *peer, count int, taskPool map[common.Hash]*typ
return request, progress, nil
}
// CancelHeaders aborts a fetch request, returning all pending skeleton indexes to the queue.
func (q *queue) CancelHeaders(request *fetchRequest) {
q.cancel(request, q.headerTaskQueue, q.headerPendPool)
}
// CancelBlocks aborts a fetch request, returning all pending hashes to the queue.
func (q *queue) CancelBlocks(request *fetchRequest) {
q.cancel(request, q.hashQueue, q.blockPendPool)
@ -663,6 +779,9 @@ func (q *queue) cancel(request *fetchRequest, taskQueue *prque.Prque, pendPool m
q.lock.Lock()
defer q.lock.Unlock()
if request.From > 0 {
taskQueue.Push(request.From, -float32(request.From))
}
for hash, index := range request.Hashes {
taskQueue.Push(hash, float32(index))
}
@ -702,6 +821,15 @@ func (q *queue) Revoke(peerId string) {
}
}
// ExpireHeaders checks for in flight requests that exceeded a timeout allowance,
// canceling them and returning the responsible peers for penalisation.
func (q *queue) ExpireHeaders(timeout time.Duration) map[string]int {
q.lock.Lock()
defer q.lock.Unlock()
return q.expire(timeout, q.headerPendPool, q.headerTaskQueue, headerTimeoutMeter)
}
// ExpireBlocks checks for in flight requests that exceeded a timeout allowance,
// canceling them and returning the responsible peers for penalisation.
func (q *queue) ExpireBlocks(timeout time.Duration) map[string]int {
@ -753,6 +881,9 @@ func (q *queue) expire(timeout time.Duration, pendPool map[string]*fetchRequest,
timeoutMeter.Mark(1)
// Return any non satisfied requests to the pool
if request.From > 0 {
taskQueue.Push(request.From, -float32(request.From))
}
for hash, index := range request.Hashes {
taskQueue.Push(hash, float32(index))
}
@ -842,6 +973,73 @@ func (q *queue) DeliverBlocks(id string, blocks []*types.Block) (int, error) {
}
}
// DeliverHeaders injects a header retrieval response into the header results
// cache. This method either accepts all headers it received, or none of them
// if they do not map correctly to the skeleton.
func (q *queue) DeliverHeaders(id string, headers []*types.Header) (int, error) {
q.lock.Lock()
defer q.lock.Unlock()
// Short circuit if the data was never requested
request := q.headerPendPool[id]
if request == nil {
return 0, errNoFetchesPending
}
headerReqTimer.UpdateSince(request.Time)
delete(q.headerPendPool, id)
// Ensure headers can be mapped onto the skeleton chain
target := q.headerTaskPool[request.From].Hash()
accepted := len(headers) == MaxHeaderFetch
if accepted {
if headers[0].Number.Uint64() != request.From {
glog.V(logger.Detail).Infof("Peer %s: first header #%v [%x] broke chain ordering, expected %d", id, headers[0].Number, headers[0].Hash().Bytes()[:4], request.From)
accepted = false
} else if headers[len(headers)-1].Hash() != target {
glog.V(logger.Detail).Infof("Peer %s: last header #%v [%x] broke skeleton structure, expected %x", id, headers[len(headers)-1].Number, headers[len(headers)-1].Hash().Bytes()[:4], target[:4])
accepted = false
}
}
if accepted {
for i, header := range headers[1:] {
hash := header.Hash()
if want := request.From + 1 + uint64(i); header.Number.Uint64() != want {
glog.V(logger.Warn).Infof("Peer %s: header #%v [%x] broke chain ordering, expected %d", id, header.Number, hash[:4], want)
accepted = false
break
}
if headers[i].Hash() != header.ParentHash {
glog.V(logger.Warn).Infof("Peer %s: header #%v [%x] broke chain ancestry", id, header.Number, hash[:4])
accepted = false
break
}
}
}
// If the batch of headers wasn't accepted, mark as unavailable
if !accepted {
glog.V(logger.Detail).Infof("Peer %s: skeleton filling from header #%d not accepted", id, request.From)
miss := q.headerPeerMiss[id]
if miss == nil {
q.headerPeerMiss[id] = make(map[uint64]struct{})
miss = q.headerPeerMiss[id]
}
miss[request.From] = struct{}{}
q.headerTaskQueue.Push(request.From, -float32(request.From))
return 0, errors.New("delivery not accepted")
}
// Clean up a successful fetch, check for termination and return
copy(q.headerResults[request.From-q.headerOffset:], headers)
delete(q.headerTaskPool, request.From)
if len(q.headerTaskPool) == 0 {
q.headerContCh <- false
}
return len(headers), nil
}
// DeliverBodies injects a block body retrieval response into the results queue.
// The method returns the number of blocks bodies accepted from the delivery and
// also wakes any threads waiting for data delivery.