From 63178ce982c9bcdf46f8cf282e90c1d4ecd7bbcd Mon Sep 17 00:00:00 2001
From: Steven Allen <steven@stebalien.com>
Date: Sat, 12 Jun 2021 11:44:38 -0700
Subject: [PATCH] feat(lotus-sim): daily capacity growth

---
 cmd/lotus-sim/info.go | 52 +++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 52 insertions(+)

diff --git a/cmd/lotus-sim/info.go b/cmd/lotus-sim/info.go
index f21adb304..591e35c80 100644
--- a/cmd/lotus-sim/info.go
+++ b/cmd/lotus-sim/info.go
@@ -93,6 +93,7 @@ var infoSimCommand = &cli.Command{
 	Subcommands: []*cli.Command{
 		infoCommitGasSimCommand,
 		infoWindowPostBandwidthSimCommand,
+		infoCapacityGrowthSimCommand,
 	},
 	Action: func(cctx *cli.Context) error {
 		node, err := open(cctx)
@@ -158,6 +159,57 @@ var infoWindowPostBandwidthSimCommand = &cli.Command{
 	},
 }
 
+var infoCapacityGrowthSimCommand = &cli.Command{
+	Name:        "capacity-growth",
+	Description: "List daily capacity growth over the course of the simulation starting at the end.",
+	Action: func(cctx *cli.Context) error {
+		node, err := open(cctx)
+		if err != nil {
+			return err
+		}
+		defer node.Close()
+
+		sim, err := node.LoadSim(cctx.Context, cctx.String("simulation"))
+		if err != nil {
+			return err
+		}
+
+		firstEpoch := sim.GetStart().Height()
+		ts := sim.GetHead()
+		lastPower, err := getTotalPower(cctx.Context, sim.StateManager, ts)
+		if err != nil {
+			return err
+		}
+		lastHeight := ts.Height()
+
+		for ts.Height() > firstEpoch && cctx.Err() == nil {
+			ts, err = sim.Chainstore.LoadTipSet(ts.Parents())
+			if err != nil {
+				return err
+			}
+			newEpoch := ts.Height()
+			if newEpoch != firstEpoch && newEpoch+builtin.EpochsInDay > lastHeight {
+				continue
+			}
+
+			newPower, err := getTotalPower(cctx.Context, sim.StateManager, ts)
+			if err != nil {
+				return err
+			}
+
+			growthRate := big.Div(
+				big.Mul(big.Sub(lastPower.RawBytePower, newPower.RawBytePower),
+					big.NewInt(builtin.EpochsInDay)),
+				big.NewInt(int64(lastHeight-newEpoch)),
+			)
+			lastPower = newPower
+			lastHeight = newEpoch
+			fmt.Fprintf(cctx.App.Writer, "%s/day\n", types.SizeStr(growthRate))
+		}
+		return cctx.Err()
+	},
+}
+
 var infoCommitGasSimCommand = &cli.Command{
 	Name:        "commit-gas",
 	Description: "Output information about the gas for commits",