From c9c437cb3bb0098a2cac12544f915f35645c8e8e Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?=C5=81ukasz=20Magiera?= <magik6k@gmail.com>
Date: Sat, 25 Jan 2020 12:15:28 +0100
Subject: [PATCH] sealing: Parallel CommP calc in pledge sector

---
 storage/sealing/garbage.go | 54 ++++++++++++++++++++++++++++++++++----
 1 file changed, 49 insertions(+), 5 deletions(-)

diff --git a/storage/sealing/garbage.go b/storage/sealing/garbage.go
index 1c3925671..a6b439258 100644
--- a/storage/sealing/garbage.go
+++ b/storage/sealing/garbage.go
@@ -6,14 +6,61 @@ import (
 	"io"
 	"math"
 	"math/rand"
+	"runtime"
+	"sync"
 
 	sectorbuilder "github.com/filecoin-project/go-sectorbuilder"
+	"github.com/hashicorp/go-multierror"
 	"golang.org/x/xerrors"
 
 	"github.com/filecoin-project/lotus/chain/actors"
 	"github.com/filecoin-project/lotus/chain/types"
 )
 
+func (m *Sealing) fastPledgeCommitment(size uint64, parts uint64) (commP [sectorbuilder.CommLen]byte, err error) {
+	piece := sectorbuilder.UserBytesForSectorSize((size / 127 + size) / parts)
+	out := make([]sectorbuilder.PublicPieceInfo, parts)
+	var lk sync.Mutex
+
+	var wg sync.WaitGroup
+	wg.Add(int(parts))
+	for i := uint64(0); i < parts; i++ {
+		go func(i uint64) {
+			defer wg.Done()
+
+			commP, perr := sectorbuilder.GeneratePieceCommitment(io.LimitReader(rand.New(rand.NewSource(42 + int64(i))), int64(piece)), piece)
+
+			lk.Lock()
+			if perr != nil {
+				err = multierror.Append(err, perr)
+			}
+			out[i] = sectorbuilder.PublicPieceInfo{
+				Size:  piece,
+				CommP: commP,
+			}
+			lk.Unlock()
+		}(i)
+	}
+	wg.Wait()
+
+	if err != nil {
+		return [32]byte{}, err
+	}
+
+	return sectorbuilder.GenerateDataCommitment(m.sb.SectorSize(), out)
+}
+
+func (m *Sealing) pledgeReader(size uint64, parts uint64) io.Reader {
+	piece := sectorbuilder.UserBytesForSectorSize((size / 127 + size) / parts)
+
+	readers := make([]io.Reader, parts)
+	for i := range readers {
+		readers[i] = io.LimitReader(rand.New(rand.NewSource(42 + int64(i))), int64(piece))
+	}
+
+	return io.MultiReader(readers...)
+}
+
 func (m *Sealing) pledgeSector(ctx context.Context, sectorID uint64, existingPieceSizes []uint64, sizes ...uint64) ([]Piece, error) {
 	if len(sizes) == 0 {
 		return nil, nil
@@ -21,10 +68,7 @@ func (m *Sealing) pledgeSector(ctx context.Context, sectorID uint64, existingPie
 
 	deals := make([]actors.StorageDealProposal, len(sizes))
 	for i, size := range sizes {
-		release := m.sb.RateLimit()
-		commP, err := sectorbuilder.GeneratePieceCommitment(io.LimitReader(rand.New(rand.NewSource(42)), int64(size)), size)
-		release()
-
+		commP, err := m.fastPledgeCommitment(size, uint64(runtime.NumCPU()))
 		if err != nil {
 			return nil, err
 		}
@@ -81,7 +125,7 @@ func (m *Sealing) pledgeSector(ctx context.Context, sectorID uint64, existingPie
 	out := make([]Piece, len(sizes))
 
 	for i, size := range sizes {
-		ppi, err := m.sb.AddPiece(size, sectorID, io.LimitReader(rand.New(rand.NewSource(42)), int64(size)), existingPieceSizes)
+		ppi, err := m.sb.AddPiece(size, sectorID, m.pledgeReader(size, uint64(runtime.NumCPU())), existingPieceSizes)
 		if err != nil {
 			return nil, err
 		}