diff options
Diffstat (limited to 'pow/ethash.go')
| -rw-r--r-- | pow/ethash.go | 26 |
1 files changed, 10 insertions, 16 deletions
diff --git a/pow/ethash.go b/pow/ethash.go index 1e577a587..9adc38540 100644 --- a/pow/ethash.go +++ b/pow/ethash.go @@ -428,7 +428,7 @@ 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) >= ethash.cachesinmem { + for len(ethash.caches) > 0 && len(ethash.caches) >= ethash.cachesinmem { var evict *cache for _, cache := range ethash.caches { if evict == nil || evict.used.After(cache.used) { @@ -480,22 +480,16 @@ func (ethash *Ethash) cache(block uint64) []uint32 { // Search implements PoW, attempting to find a nonce that satisfies the block's // difficulty requirements. func (ethash *Ethash) Search(block Block, stop <-chan struct{}) (uint64, []byte) { - // Extract some data from the block - var ( - hash = block.HashNoNonce().Bytes() - diff = block.Difficulty() - target = new(big.Int).Div(maxUint256, diff) - ) - // Retrieve the mining dataset - dataset, size := ethash.dataset(block.NumberU64()), datasetSize(block.NumberU64()) - - // Start generating random nonces until we abort or find a good one var ( + hash = block.HashNoNonce().Bytes() + diff = block.Difficulty() + target = new(big.Int).Div(maxUint256, diff) + dataset = ethash.dataset(block.NumberU64()) + rand = rand.New(rand.NewSource(time.Now().UnixNano())) + nonce = uint64(rand.Int63()) attempts int64 - - rand = rand.New(rand.NewSource(time.Now().UnixNano())) - nonce = uint64(rand.Int63()) ) + // Start generating random nonces until we abort or find a good one for { select { case <-stop: @@ -511,7 +505,7 @@ func (ethash *Ethash) Search(block Block, stop <-chan struct{}) (uint64, []byte) attempts = 0 } // Compute the PoW value of this nonce - digest, result := hashimotoFull(size, dataset, hash, nonce) + digest, result := hashimotoFull(dataset, hash, nonce) if new(big.Int).SetBytes(result).Cmp(target) <= 0 { return nonce, digest } @@ -532,7 +526,7 @@ func (ethash *Ethash) dataset(block uint64) []uint32 { current, future := ethash.datasets[epoch], (*dataset)(nil) if current == nil { // No in-memory dataset, evict the oldest if the dataset limit was reached - for len(ethash.datasets) >= ethash.dagsinmem { + for len(ethash.datasets) > 0 && len(ethash.datasets) >= ethash.dagsinmem { var evict *dataset for _, dataset := range ethash.datasets { if evict == nil || evict.used.After(dataset.used) { |