func TestCurrencyUnits(t *testing.T) {
tests := []struct {
in, out string
}{
{"1", "1 H"},
{"1000", "1000 H"},
{"100000000000", "100000000000 H"},
{"1000000000000", "1 pS"},
{"1234560000000", "1.235 pS"},
{"12345600000000", "12.35 pS"},
{"123456000000000", "123.5 pS"},
{"1000000000000000", "1 nS"},
{"1000000000000000000", "1 uS"},
{"1000000000000000000000", "1 mS"},
{"1000000000000000000000000", "1 SC"},
{"1000000000000000000000000000", "1 KS"},
{"1000000000000000000000000000000", "1 MS"},
{"1000000000000000000000000000000000", "1 GS"},
{"1000000000000000000000000000000000000", "1 TS"},
{"1234560000000000000000000000000000000", "1.235 TS"},
{"1234560000000000000000000000000000000000", "1235 TS"},
}
for _, test := range tests {
i, _ := new(big.Int).SetString(test.in, 10)
out := currencyUnits(types.NewCurrency(i))
if out != test.out {
t.Errorf("currencyUnits(%v): expected %v, got %v", test.in, test.out, out)
}
}
}
// RandomHosts will pull up to 'num' random hosts from the hostdb. There will
// be no repeats, but the length of the slice returned may be less than 'num',
// and may even be 0. The hosts that get returned first have the higher
// priority.
func (hdb *HostDB) RandomHosts(count int) (hosts []modules.HostSettings) {
id := hdb.mu.Lock()
defer hdb.mu.Unlock(id)
var removedEntries []*hostEntry
for len(hosts) < count {
if hdb.hostTree == nil || hdb.hostTree.weight.IsZero() {
break
}
randWeight, err := rand.Int(rand.Reader, hdb.hostTree.weight.Big())
if err != nil {
break
}
node, err := hdb.hostTree.nodeAtWeight(types.NewCurrency(randWeight))
if err != nil {
break
}
hosts = append(hosts, node.hostEntry.HostSettings)
node.removeNode()
delete(hdb.activeHosts, node.hostEntry.IPAddress)
// remove the entry from the hostdb so it won't be selected as a
// repeat.
removedEntries = append(removedEntries, node.hostEntry)
}
// Add back all of the entries that got removed.
for _, entry := range removedEntries {
hdb.insertNode(entry)
}
return hosts
}
// scanAmount scans a types.Currency from a string.
func scanAmount(amount string) (types.Currency, bool) {
// use SetString manually to ensure that amount does not contain
// multiple values, which would confuse fmt.Scan
i, ok := new(big.Int).SetString(amount, 10)
if !ok {
return types.Currency{}, ok
}
return types.NewCurrency(i), true
}
// hostconfigcmd is the handler for the command `siac host config [setting] [value]`.
// Modifies host settings.
func hostconfigcmd(param, value string) {
switch param {
// currency (convert to hastings)
case "collateralbudget", "maxcollateral", "mincontractprice":
hastings, err := parseCurrency(value)
if err != nil {
die("Could not parse "+param+":", err)
}
value = hastings
// currency/TB (convert to hastings/byte)
case "mindownloadbandwidthprice", "minuploadbandwidthprice":
hastings, err := parseCurrency(value)
if err != nil {
die("Could not parse "+param+":", err)
}
i, _ := new(big.Int).SetString(hastings, 10)
c := types.NewCurrency(i).Div(modules.BytesPerTerabyte)
value = c.String()
// currency/TB/month (convert to hastings/byte/block)
case "collateral", "minstorageprice":
hastings, err := parseCurrency(value)
if err != nil {
die("Could not parse "+param+":", err)
}
i, _ := new(big.Int).SetString(hastings, 10)
c := types.NewCurrency(i).Div(modules.BlockBytesPerMonthTerabyte)
value = c.String()
// other valid settings
case "acceptingcontracts", "maxdownloadbatchsize", "maxduration",
"maxrevisebatchsize", "netaddress", "windowsize":
// invalid settings
default:
die("\"" + param + "\" is not a host setting")
}
err := post("/host", param+"="+value)
if err != nil {
die("Could not update host settings:", err)
}
fmt.Println("Host settings updated.")
}
// Returns many pieces of readily available information
func (e *Explorer) Statistics() modules.ExplorerStatistics {
e.mu.RLock()
defer e.mu.RUnlock()
target, _ := e.cs.ChildTarget(e.currentBlock)
difficulty := types.NewCurrency(types.RootTarget.Int()).Div(types.NewCurrency(target.Int()))
currentBlock, exists := e.cs.BlockAtHeight(e.blockchainHeight)
if build.DEBUG && !exists {
panic("current block not found in consensus set")
}
return modules.ExplorerStatistics{
Height: e.blockchainHeight,
CurrentBlock: e.currentBlock,
Target: target,
Difficulty: difficulty,
MaturityTimestamp: currentBlock.Timestamp,
TotalCoins: types.CalculateNumSiacoins(e.blockchainHeight),
MinerPayoutCount: e.minerPayoutCount,
TransactionCount: e.transactionCount,
SiacoinInputCount: e.siacoinInputCount,
SiacoinOutputCount: e.siacoinOutputCount,
FileContractCount: e.fileContractCount,
FileContractRevisionCount: e.fileContractRevisionCount,
StorageProofCount: e.storageProofCount,
SiafundInputCount: e.siafundInputCount,
SiafundOutputCount: e.siafundOutputCount,
MinerFeeCount: e.minerFeeCount,
ArbitraryDataCount: e.arbitraryDataCount,
TransactionSignatureCount: e.transactionSignatureCount,
ActiveContractCount: e.activeContractCount,
ActiveContractCost: e.activeContractCost,
ActiveContractSize: e.activeContractSize,
TotalContractCost: e.totalContractCost,
TotalContractSize: e.totalContractSize,
}
}
// RandomHosts will pull up to 'n' random hosts from the hostdb. There will be
// no repeats, but the length of the slice returned may be less than 'n', and
// may even be 0. The hosts that get returned first have the higher priority.
// Hosts specified in 'ignore' will not be considered; pass 'nil' if no
// blacklist is desired.
func (hdb *HostDB) RandomHosts(n int, ignore []modules.NetAddress) (hosts []modules.HostDBEntry) {
hdb.mu.Lock()
defer hdb.mu.Unlock()
if hdb.isEmpty() {
return
}
// These will be restored after selection is finished.
var removedEntries []*hostEntry
// Remove hosts that we want to ignore.
for _, addr := range ignore {
node, exists := hdb.activeHosts[addr]
if !exists {
continue
}
node.removeNode()
delete(hdb.activeHosts, addr)
removedEntries = append(removedEntries, node.hostEntry)
}
// Pick a host, remove it from the tree, and repeat until we have n hosts
// or the tree is empty.
for len(hosts) < n && !hdb.isEmpty() {
randWeight, err := rand.Int(rand.Reader, hdb.hostTree.weight.Big())
if err != nil {
build.Critical("rand.Int is returning an error:", err)
break
}
node, err := hdb.hostTree.nodeAtWeight(types.NewCurrency(randWeight))
if err != nil {
build.Critical("nodeAtWeight is returning and error:", err)
break
}
// Only return the host if they are accepting contracts.
if node.hostEntry.HostDBEntry.AcceptingContracts {
hosts = append(hosts, node.hostEntry.HostDBEntry)
}
removedEntries = append(removedEntries, node.hostEntry)
node.removeNode()
delete(hdb.activeHosts, node.hostEntry.NetAddress)
}
// Add back all of the entries that got removed.
for i := range removedEntries {
hdb.insertNode(removedEntries[i])
}
return hosts
}
// randomHosts will pull up to 'n' random hosts from the hostdb. There will be
// no repeats, but the length of the slice returned may be less than 'n', and
// may even be 0. The hosts that get returned first have the higher priority.
// Hosts specified in 'ignore' will not be considered; pass 'nil' if no
// blacklist is desired.
func (hdb *HostDB) randomHosts(n int, ignore []modules.NetAddress) (hosts []modules.HostSettings) {
if hdb.isEmpty() {
return
}
// These will be restored after selection is finished.
var removedEntries []*hostEntry
// Remove hosts that we want to ignore.
for _, addr := range ignore {
node, exists := hdb.activeHosts[addr]
if !exists {
continue
}
node.removeNode()
delete(hdb.activeHosts, addr)
removedEntries = append(removedEntries, node.hostEntry)
}
// Pick a host, remove it from the tree, and repeat until we have n hosts
// or the tree is empty.
for len(hosts) < n && !hdb.isEmpty() {
randWeight, err := rand.Int(rand.Reader, hdb.hostTree.weight.Big())
if err != nil {
break
}
node, err := hdb.hostTree.nodeAtWeight(types.NewCurrency(randWeight))
if err != nil {
break
}
hosts = append(hosts, node.hostEntry.HostSettings)
node.removeNode()
delete(hdb.activeHosts, node.hostEntry.NetAddress)
removedEntries = append(removedEntries, node.hostEntry)
}
// Add back all of the entries that got removed.
for i := range removedEntries {
hdb.insertNode(removedEntries[i])
}
return hosts
}
// uniformTreeVerification checks that everything makes sense in the tree given
// the number of entries that the tree is supposed to have and also given that
// every entropy has the same weight.
func (hdbt *hdbTester) uniformTreeVerification(numEntries int) error {
// Check that the weight of the hostTree is what is expected.
expectedWeight := types.NewCurrency64(uint64(numEntries)).Mul(hdbt.hostdb.hostTree.hostEntry.weight)
if hdbt.hostdb.hostTree.weight.Cmp(expectedWeight) != 0 {
return errors.New("expected weight is incorrect")
}
// Check that the length of activeHosts and the count of hostTree are
// consistent.
if len(hdbt.hostdb.activeHosts) != numEntries {
return errors.New("unexpected number of active hosts")
}
// Select many random hosts and do naive statistical analysis on the
// results.
if !testing.Short() {
// Pull a bunch of random hosts and count how many times we pull each
// host.
selectionMap := make(map[modules.NetAddress]int)
expected := 100
for i := 0; i < expected*numEntries; i++ {
entries := hdbt.hostdb.RandomHosts(1)
if len(entries) == 0 {
return errors.New("no hosts!")
}
selectionMap[entries[0].IPAddress] = selectionMap[entries[0].IPAddress] + 1
}
// See if each host was selected enough times.
errorBound := 64 // Pretty large, but will still detect if something is seriously wrong.
for _, count := range selectionMap {
if count < expected-errorBound || count > expected+errorBound {
return errors.New("error bound was breached")
}
}
}
// Try removing an re-adding all hosts.
var removedEntries []*hostEntry
for {
if hdbt.hostdb.hostTree.weight.IsZero() {
break
}
randWeight, err := rand.Int(rand.Reader, hdbt.hostdb.hostTree.weight.Big())
if err != nil {
break
}
node, err := hdbt.hostdb.hostTree.nodeAtWeight(types.NewCurrency(randWeight))
if err != nil {
break
}
node.removeNode()
delete(hdbt.hostdb.activeHosts, node.hostEntry.IPAddress)
// remove the entry from the hostdb so it won't be selected as a
// repeat.
removedEntries = append(removedEntries, node.hostEntry)
}
for _, entry := range removedEntries {
hdbt.hostdb.insertNode(entry)
}
return nil
}
package hostdb
import (
"math/big"
"github.com/NebulousLabs/Sia/types"
)
var (
// Because most weights would otherwise be fractional, we set the base
// weight to 10^80 to give ourselves lots of precision when determing the
// weight of a host
baseWeight = types.NewCurrency(new(big.Int).Exp(big.NewInt(10), big.NewInt(150), nil))
)
// calculateHostWeight returns the weight of a host according to the settings of
// the host database entry. Currently, only the price is considered.
func calculateHostWeight(entry hostEntry) (weight types.Currency) {
// If the price is 0, just return the base weight to avoid divide by zero.
price := entry.Price
if price.IsZero() {
return baseWeight
}
// Divide the base weight by the price to the fifth power.
return baseWeight.Div(price).Div(price).Div(price).Div(price).Div(price)
}