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cmd, eth, les, node, pow: disk caching and progress reports

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This commit is contained in:
Péter Szilágyi
2017-03-09 15:50:14 +01:00
committed by Felix Lange
parent 567d41d936
commit 023670f6ba
8 changed files with 216 additions and 55 deletions
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pow/ethash.go
+95 -26
View File
@@ -17,12 +17,19 @@
package pow
import (
"bufio"
"bytes"
"errors"
"fmt"
"io/ioutil"
"math/big"
"os"
"path/filepath"
"sync"
"time"
"github.com/ethereum/go-ethereum/common"
"github.com/ethereum/go-ethereum/common/hexutil"
"github.com/ethereum/go-ethereum/log"
metrics "github.com/rcrowley/go-metrics"
)
@@ -36,6 +43,15 @@ var (
var (
// maxUint256 is a big integer representing 2^256-1
maxUint256 = new(big.Int).Exp(big.NewInt(2), big.NewInt(256), big.NewInt(0))
// sharedEthash is a full instance that can be shared between multiple users.
sharedEthash = NewFullEthash("", 3, 0, "", 0)
// algorithmRevision is the data structure version used for file naming.
algorithmRevision = 23
// dumpMagic is a dataset dump header to sanity check a data dump.
dumpMagic = hexutil.MustDecode("0xfee1deadbaddcafe")
)
// cache wraps an ethash cache with some metadata to allow easier concurrent use.
@@ -48,21 +64,65 @@ type cache struct {
}
// generate ensures that the cache content is generates.
func (c *cache) generate(test bool) {
func (c *cache) generate(dir string, limit int, test bool) {
c.once.Do(func() {
cacheSize := cacheSize(c.epoch*epochLength + 1)
// If we have a testing cache, generate and return
if test {
cacheSize = 1024
rawCache := generateCache(1024, seedHash(c.epoch*epochLength+1))
c.cache = prepare(uint64(len(rawCache)), bytes.NewReader(rawCache))
return
}
// Full cache generation is needed, check cache dir for existing data
size := cacheSize(c.epoch*epochLength + 1)
seed := seedHash(c.epoch*epochLength + 1)
path := filepath.Join(dir, fmt.Sprintf("cache-R%d-%x", algorithmRevision, seed))
logger := log.New("seed", hexutil.Bytes(seed))
if dir != "" {
dump, err := os.Open(path)
if err == nil {
logger.Info("Loading ethash cache from disk")
start := time.Now()
c.cache = prepare(size, bufio.NewReader(dump))
logger.Info("Loaded ethash cache from disk", "elapsed", common.PrettyDuration(time.Since(start)))
dump.Close()
return
}
}
// No previous disk cache was available, generate on the fly
rawCache := generateCache(size, seed)
c.cache = prepare(size, bytes.NewReader(rawCache))
// If a cache directory is given, attempt to serialize for next time
if dir != "" {
// Store the ethash cache to disk
start := time.Now()
if err := os.MkdirAll(filepath.Dir(path), os.ModePerm); err != nil {
logger.Error("Failed to create ethash cache dir", "err", err)
} else if err := ioutil.WriteFile(path, rawCache, os.ModePerm); err != nil {
logger.Error("Failed to write ethash cache to disk", "err", err)
} else {
logger.Info("Stored ethash cache to disk", "elapsed", common.PrettyDuration(time.Since(start)))
}
// Iterate over all previous instances and delete old ones
for ep := int(c.epoch) - limit; ep >= 0; ep-- {
seed := seedHash(uint64(ep)*epochLength + 1)
path := filepath.Join(dir, fmt.Sprintf("cache-R%d-%x", algorithmRevision, seed))
os.Remove(path)
}
}
rawCache := generateCache(cacheSize, seedHash(c.epoch*epochLength+1))
c.cache = prepare(uint64(len(rawCache)), bytes.NewReader(rawCache))
})
}
// Ethash is a PoW data struture implementing the ethash algorithm.
type Ethash struct {
cachedir string // Data directory to store the verification caches
dagdir string // Data directory to store full mining datasets
cachedir string // Data directory to store the verification caches
cachesinmem int // Number of caches to keep in memory
cachesondisk int // Number of caches to keep on disk
dagdir string // Data directory to store full mining datasets
dagsondisk int // Number of mining datasets to keep on disk
caches map[uint64]*cache // In memory caches to avoid regenerating too often
future *cache // Pre-generated cache for the estimated future epoch
@@ -71,15 +131,27 @@ type Ethash struct {
hashrate *metrics.StandardMeter // Meter tracking the average hashrate
tester bool // Flag whether to use a smaller test dataset
shared bool // Flag whether to use a global chared dataset
}
// NewFullEthash creates a full sized ethash PoW scheme.
func NewFullEthash(cachedir, dagdir string) PoW {
func NewFullEthash(cachedir string, cachesinmem, cachesondisk int, dagdir string, dagsondisk int) PoW {
if cachesinmem <= 0 {
log.Warn("One ethash cache must alwast be in memory", "requested", cachesinmem)
cachesinmem = 1
}
if cachedir != "" && cachesondisk > 0 {
log.Info("Disk storage enabled for ethash caches", "dir", cachedir, "count", cachesondisk)
}
if dagdir != "" && dagsondisk > 0 {
log.Info("Disk storage enabled for ethash DAGs", "dir", dagdir, "count", dagsondisk)
}
return &Ethash{
cachedir: cachedir,
dagdir: dagdir,
caches: make(map[uint64]*cache),
cachedir: cachedir,
cachesinmem: cachesinmem,
cachesondisk: cachesondisk,
dagdir: dagdir,
dagsondisk: dagsondisk,
caches: make(map[uint64]*cache),
}
}
@@ -87,18 +159,16 @@ func NewFullEthash(cachedir, dagdir string) PoW {
// purposes.
func NewTestEthash() PoW {
return &Ethash{
caches: make(map[uint64]*cache),
tester: true,
cachesinmem: 1,
caches: make(map[uint64]*cache),
tester: true,
}
}
// NewSharedEthash creates a full sized ethash PoW shared between all requesters
// running in the same process.
func NewSharedEthash() PoW {
return &Ethash{
caches: make(map[uint64]*cache),
shared: true,
}
return sharedEthash
}
// Verify implements PoW, checking whether the given block satisfies the PoW
@@ -140,7 +210,7 @@ func (ethash *Ethash) cache(block uint64) []uint32 {
current, future := ethash.caches[epoch], (*cache)(nil)
if current == nil {
// No in-memory cache, evict the oldest if the cache limit was reached
for len(ethash.caches) >= 3 {
for len(ethash.caches) >= ethash.cachesinmem {
var evict *cache
for _, cache := range ethash.caches {
if evict == nil || evict.used.After(cache.used) {
@@ -149,21 +219,21 @@ func (ethash *Ethash) cache(block uint64) []uint32 {
}
delete(ethash.caches, evict.epoch)
log.Debug("Evictinged ethash cache", "old", evict.epoch, "used", evict.used)
log.Debug("Evicted ethash cache", "epoch", evict.epoch, "used", evict.used)
}
// If we have the new cache pre-generated, use that, otherwise create a new one
if ethash.future != nil && ethash.future.epoch == epoch {
log.Debug("Using pre-generated cache", "epoch", epoch)
current, ethash.future = ethash.future, nil
} else {
log.Debug("Generating new ethash cache", "epoch", epoch)
log.Debug("Requiring new ethash cache", "epoch", epoch)
current = &cache{epoch: epoch}
}
ethash.caches[epoch] = current
// If we just used up the future cache, or need a refresh, regenerate
if ethash.future == nil || ethash.future.epoch <= epoch {
log.Debug("Pre-generating cache for the future", "epoch", epoch+1)
log.Debug("Requiring new future ethash cache", "epoch", epoch+1)
future = &cache{epoch: epoch + 1}
ethash.future = future
}
@@ -172,16 +242,15 @@ func (ethash *Ethash) cache(block uint64) []uint32 {
ethash.lock.Unlock()
// Wait for generation finish, bump the timestamp and finalize the cache
current.once.Do(func() {
current.generate(ethash.tester)
})
current.generate(ethash.cachedir, ethash.cachesondisk, ethash.tester)
current.lock.Lock()
current.used = time.Now()
current.lock.Unlock()
// If we exhusted the future cache, now's a goot time to regenerate it
if future != nil {
go future.generate(ethash.tester)
go future.generate(ethash.cachedir, ethash.cachesondisk, ethash.tester)
}
return current.cache
}
pow/ethash_algo.go
+25 -11
View File
@@ -45,12 +45,6 @@ const (
loopAccesses = 64 // Number of accesses in hashimoto loop
)
var (
// Metadata fields to be compatible with the C++ ethash
ethashRevision = 23 // Data structure version
ethashMagic = hexutil.MustDecode("0xfee1deadbaddcafe") // Dataset dump magic number
)
// cacheSize calculates and returns the size of the ethash verification cache that
// belongs to a certain block number. The cache size grows linearly, however, we
// always take the highest prime below the linearly growing threshold in order to
@@ -108,16 +102,33 @@ func seedHash(block uint64) []byte {
// set of 524288 64-byte values.
func generateCache(size uint64, seed []byte) []byte {
// Print some debug logs to allow analysis on low end devices
logger := log.New("size", size, "seed", hexutil.Bytes(seed))
logger.Debug("Generating ethash cache")
logger := log.New("seed", hexutil.Bytes(seed))
logger.Debug("Generating ethash verification cache")
defer func(start time.Time) {
logger.Debug("Generated ethash cache", "elapsed", common.PrettyDuration(time.Since(start)))
}(time.Now())
start := time.Now()
defer func() {
logger.Info("Generated ethash verification cache", "elapsed", common.PrettyDuration(time.Since(start)))
}()
// Calculate the number of thoretical rows (we'll store in one buffer nonetheless)
rows := int(size) / hashBytes
// Start a monitoring goroutine to report progress on low end devices
var progress uint32
done := make(chan struct{})
defer close(done)
go func() {
for {
select {
case <-done:
return
case <-time.After(3 * time.Second):
logger.Info("Generating ethash verification cache", "percentage", atomic.LoadUint32(&progress)*100/uint32(rows)/4, "elapsed", common.PrettyDuration(time.Since(start)))
}
}
}()
// Create a hasher to reuse between invocations
keccak512 := crypto.Keccak512Hasher()
@@ -126,6 +137,7 @@ func generateCache(size uint64, seed []byte) []byte {
copy(cache, keccak512(seed))
for offset := uint64(hashBytes); offset < size; offset += hashBytes {
copy(cache[offset:], keccak512(cache[offset-hashBytes:offset]))
atomic.AddUint32(&progress, 1)
}
// Use a low-round version of randmemohash
temp := make([]byte, hashBytes)
@@ -139,6 +151,8 @@ func generateCache(size uint64, seed []byte) []byte {
)
xorBytes(temp, cache[srcOff:srcOff+hashBytes], cache[xorOff:xorOff+hashBytes])
copy(cache[dstOff:], keccak512(temp))
atomic.AddUint32(&progress, 1)
}
}
return cache