Cache targetHex per endpoint

go-pool/stratum/miner.go

@@ -66,7 +66,7 @@ func (cs *Session) getJob(t *BlockTemplate) *JobReplyData {
 	job := &Job{id: strconv.FormatUint(id, 10), extraNonce: extraNonce, height: t.height, difficulty: cs.difficulty}
 	job.submissions = make(map[string]struct{})
 	cs.pushJob(job)
-	reply := &JobReplyData{JobId: job.id, Blob: blob, Target: cs.targetHex}
+	reply := &JobReplyData{JobId: job.id, Blob: blob, Target: cs.endpoint.targetHex}
 	return reply
 }
 

go-pool/stratum/stratum.go

@@ -38,6 +38,7 @@ type Endpoint struct {
 	config      *pool.Port
 	instanceId  []byte
 	extraNonce  uint32
+	targetHex   string
 	jobSequence uint64
 }
 
@@ -50,8 +51,6 @@ type Session struct {
 	difficulty      int64
 	validJobs       []*Job
 	lastBlockHeight int64
-	target          uint32
-	targetHex       string
 }
 
 const (
@@ -127,6 +126,7 @@ func NewEndpoint(cfg *pool.Port) *Endpoint {
 	if err != nil {
 		log.Fatalf("Can't seed with random bytes: %v", err)
 	}
+	e.targetHex = util.GetTargetHex(e.config.Difficulty)
 	return e
 }
 
@@ -176,9 +176,6 @@ func (e *Endpoint) Listen(s *StratumServer) {
 }
 
 func (s *StratumServer) handleClient(cs *Session, e *Endpoint) {
-	_, targetHex := util.GetTargetHex(e.config.Difficulty)
-	cs.targetHex = targetHex
-
 	connbuff := bufio.NewReaderSize(cs.conn, MaxReqSize)
 	s.setDeadline(cs.conn)
 

go-pool/util/util.go

@@ -1,8 +1,6 @@
 package util
 
 import (
-	"bytes"
-	"encoding/binary"
 	"encoding/hex"
 	"math/big"
 	"time"
@@ -22,24 +20,14 @@ func MakeTimestamp() int64 {
 	return time.Now().UnixNano() / int64(time.Millisecond)
 }
 
-func GetTargetHex(diff int64) (uint32, string) {
+func GetTargetHex(diff int64) string {
 	padded := make([]byte, 32)
 
-	diff2 := new(big.Int)
-	diff2.SetInt64(int64(diff))
-
-	diff3 := new(big.Int)
-	diff3 = diff3.Div(Diff1, diff2)
-
-	diffBuff := diff3.Bytes()
+	diffBuff := new(big.Int).Div(Diff1, big.NewInt(diff)).Bytes()
 	copy(padded[32-len(diffBuff):], diffBuff)
 	buff := padded[0:4]
-	var target uint32
-	targetBuff := bytes.NewReader(buff)
-	binary.Read(targetBuff, binary.LittleEndian, &target)
 	targetHex := hex.EncodeToString(reverse(buff))
-
-	return target, targetHex
+	return targetHex
 }
 
 func GetHashDifficulty(hashBytes []byte) *big.Int {