downloader: moved chunk ignoring. Fixes issue with catching up

This commit is contained in:
obscuren 2015-04-19 13:30:34 +02:00
parent 4340996572
commit c58918c84a
4 changed files with 44 additions and 31 deletions

@ -18,14 +18,15 @@ import (
)
const (
maxBlockFetch = 256 // Amount of max blocks to be fetched per chunk
minDesiredPeerCount = 5 // Amount of peers desired to start syncing
peerCountTimeout = 12 * time.Second // Amount of time it takes for the peer handler to ignore minDesiredPeerCount
blockTtl = 15 * time.Second // The amount of time it takes for a block request to time out
hashTtl = 20 * time.Second // The amount of time it takes for a hash request to time out
maxBlockFetch = 256 // Amount of max blocks to be fetched per chunk
peerCountTimeout = 12 * time.Second // Amount of time it takes for the peer handler to ignore minDesiredPeerCount
blockTtl = 20 * time.Second // The amount of time it takes for a block request to time out
hashTtl = 20 * time.Second // The amount of time it takes for a hash request to time out
)
var (
minDesiredPeerCount = 5 // Amount of peers desired to start syncing
errLowTd = errors.New("peer's TD is too low")
errBusy = errors.New("busy")
errUnknownPeer = errors.New("peer's unknown or unhealthy")
@ -127,11 +128,11 @@ out:
for {
select {
case <-d.newPeerCh:
itimer.Stop()
// Meet the `minDesiredPeerCount` before we select our best peer
if len(d.peers) < minDesiredPeerCount {
break
}
itimer.Stop()
d.selectPeer(d.peers.bestPeer())
case <-itimer.C:
@ -154,17 +155,18 @@ func (d *Downloader) selectPeer(p *peer) {
// Make sure it's doing neither. Once done we can restart the
// downloading process if the TD is higher. For now just get on
// with whatever is going on. This prevents unecessary switching.
if !d.isBusy() {
// selected peer must be better than our own
// XXX we also check the peer's recent hash to make sure we
// don't have it. Some peers report (i think) incorrect TD.
if p.td.Cmp(d.currentTd()) <= 0 || d.hasBlock(p.recentHash) {
return
}
glog.V(logger.Detail).Infoln("New peer with highest TD =", p.td)
d.syncCh <- syncPack{p, p.recentHash, false}
if d.isBusy() {
return
}
// selected peer must be better than our own
// XXX we also check the peer's recent hash to make sure we
// don't have it. Some peers report (i think) incorrect TD.
if p.td.Cmp(d.currentTd()) <= 0 || d.hasBlock(p.recentHash) {
return
}
glog.V(logger.Detail).Infoln("New peer with highest TD =", p.td)
d.syncCh <- syncPack{p, p.recentHash, false}
}
@ -282,6 +284,8 @@ out:
// If there are unrequested hashes left start fetching
// from the available peers.
if d.queue.hashPool.Size() > 0 {
was := d.queue.hashPool.Size()
fmt.Println("it was =", was)
availablePeers := d.peers.get(idleState)
for _, peer := range availablePeers {
// Get a possible chunk. If nil is returned no chunk
@ -301,13 +305,14 @@ out:
d.queue.put(chunk.hashes)
}
}
fmt.Println("it is =", d.queue.hashPool.Size())
// make sure that we have peers available for fetching. If all peers have been tried
// and all failed throw an error
if len(d.queue.fetching) == 0 {
d.queue.reset()
return fmt.Errorf("%v avaialable = %d. total = %d", errPeersUnavailable, len(availablePeers), len(d.peers))
return fmt.Errorf("%v peers avaialable = %d. total peers = %d. hashes needed = %d", errPeersUnavailable, len(availablePeers), len(d.peers), d.queue.hashPool.Size())
}
} else if len(d.queue.fetching) == 0 {

@ -73,7 +73,7 @@ func (dl *downloadTester) insertChain(blocks types.Blocks) error {
}
func (dl *downloadTester) getHashes(hash common.Hash) error {
dl.downloader.HashCh <- dl.hashes
dl.downloader.hashCh <- dl.hashes
return nil
}
@ -109,6 +109,8 @@ func TestDownload(t *testing.T) {
glog.SetV(logger.Detail)
glog.SetToStderr(true)
minDesiredPeerCount = 4
hashes := createHashes(0, 1000)
blocks := createBlocksFromHashes(hashes)
tester := newTester(t, hashes, blocks)
@ -123,7 +125,7 @@ success:
case <-tester.done:
break success
case <-time.After(10 * time.Second): // XXX this could actually fail on a slow computer
t.Error("timout")
t.Error("timeout")
}
}

@ -71,7 +71,7 @@ type peer struct {
td *big.Int
recentHash common.Hash
requested *set.Set
ignored *set.Set
getHashes hashFetcherFn
getBlocks blockFetcherFn
@ -86,7 +86,7 @@ func newPeer(id string, td *big.Int, hash common.Hash, getHashes hashFetcherFn,
getHashes: getHashes,
getBlocks: getBlocks,
state: idleState,
requested: set.New(),
ignored: set.New(),
}
}
@ -99,8 +99,6 @@ func (p *peer) fetch(chunk *chunk) error {
return errors.New("peer already fetching chunk")
}
p.requested.Merge(chunk.hashes)
// set working state
p.state = workingState
// convert the set to a fetchable slice
@ -137,5 +135,5 @@ func (p *peer) demote() {
func (p *peer) reset() {
p.state = idleState
p.requested.Clear()
p.ignored.Clear()
}

@ -56,16 +56,18 @@ func (c *queue) get(p *peer, max int) *chunk {
// Create a new set of hashes
hashes, i := set.New(), 0
c.hashPool.Each(func(v interface{}) bool {
// break on limit
if i == limit {
return false
}
// Skip any hashes that have previously been requested from the peer
if !p.requested.Has(v) {
hashes.Add(v)
i++
// skip any hashes that have previously been requested from the peer
if p.ignored.Has(v) {
return true
}
hashes.Add(v)
i++
return true
})
// if no hashes can be requested return a nil chunk
@ -79,7 +81,7 @@ func (c *queue) get(p *peer, max int) *chunk {
// Create a new chunk for the seperated hashes. The time is being used
// to reset the chunk (timeout)
chunk := &chunk{hashes, time.Now()}
chunk := &chunk{p, hashes, time.Now()}
// register as 'fetching' state
c.fetching[p.id] = chunk
@ -111,6 +113,12 @@ func (c *queue) deliver(id string, blocks []*types.Block) {
// If the chunk was never requested simply ignore it
if chunk != nil {
delete(c.fetching, id)
// check the length of the returned blocks. If the length of blocks is 0
// we'll assume the peer doesn't know about the chain.
if len(blocks) == 0 {
// So we can ignore the blocks we didn't know about
chunk.peer.ignored.Merge(chunk.hashes)
}
// seperate the blocks and the hashes
blockHashes := chunk.fetchedHashes(blocks)
@ -118,7 +126,6 @@ func (c *queue) deliver(id string, blocks []*types.Block) {
c.blockHashes.Merge(blockHashes)
// Add the blocks
c.blocks = append(c.blocks, blocks...)
// Add back whatever couldn't be delivered
c.hashPool.Merge(chunk.hashes)
c.fetchPool.Separate(chunk.hashes)
@ -134,6 +141,7 @@ func (c *queue) put(hashes *set.Set) {
}
type chunk struct {
peer *peer
hashes *set.Set
itime time.Time
}