From ee41547c52f97b82aeab6bf50070a2597e8bab20 Mon Sep 17 00:00:00 2001
From: vyzo <vyzo@hackzen.org>
Date: Fri, 3 Dec 2021 11:50:35 +0200
Subject: [PATCH] add logic for supressing compaction near upgrade boundaries

---
 blockstore/splitstore/splitstore.go         | 32 ++++++++++++++++++++-
 blockstore/splitstore/splitstore_compact.go | 16 +++++++++++
 2 files changed, 47 insertions(+), 1 deletion(-)

diff --git a/blockstore/splitstore/splitstore.go b/blockstore/splitstore/splitstore.go
index 0e34fe952..e0366512f 100644
--- a/blockstore/splitstore/splitstore.go
+++ b/blockstore/splitstore/splitstore.go
@@ -18,6 +18,8 @@ import (
 
 	"github.com/filecoin-project/go-state-types/abi"
 	bstore "github.com/filecoin-project/lotus/blockstore"
+	"github.com/filecoin-project/lotus/build"
+	"github.com/filecoin-project/lotus/chain/stmgr"
 	"github.com/filecoin-project/lotus/chain/types"
 	"github.com/filecoin-project/lotus/metrics"
 
@@ -47,6 +49,9 @@ var (
 	enableDebugLog = false
 	// set this to true if you want to track origin stack traces in the write log
 	enableDebugLogWriteTraces = false
+
+	// upgradeBoundary is the boundary before and after an upgrade where we supress compaction
+	upgradeBoundary = build.Finality
 )
 
 func init() {
@@ -98,6 +103,12 @@ type ChainAccessor interface {
 	SubscribeHeadChanges(change func(revert []*types.TipSet, apply []*types.TipSet) error)
 }
 
+// upgradeRange is a precomputed epoch range during which we shouldn't compact so as to not
+// interfere with an upgrade
+type upgradeRange struct {
+	start, end abi.ChainEpoch
+}
+
 // hotstore is the interface that must be satisfied by the hot blockstore; it is an extension
 // of the Blockstore interface with the traits we need for compaction.
 type hotstore interface {
@@ -125,6 +136,8 @@ type SplitStore struct {
 	cold  bstore.Blockstore
 	hot   hotstore
 
+	upgrades []upgradeRange
+
 	markSetEnv  MarkSetEnv
 	markSetSize int64
 
@@ -463,10 +476,27 @@ func (s *SplitStore) isWarm() bool {
 }
 
 // State tracking
-func (s *SplitStore) Start(chain ChainAccessor) error {
+func (s *SplitStore) Start(chain ChainAccessor, us stmgr.UpgradeSchedule) error {
 	s.chain = chain
 	curTs := chain.GetHeaviestTipSet()
 
+	// precompute the upgrade boundaries
+	s.upgrades = make([]upgradeRange, 0, len(us))
+	for _, upgrade := range us {
+		boundary := upgrade.Height
+		for _, pre := range upgrade.PreMigrations {
+			preMigrationBoundary := upgrade.Height - pre.StartWithin
+			if preMigrationBoundary < boundary {
+				boundary = preMigrationBoundary
+			}
+		}
+
+		upgradeStart := boundary - upgradeBoundary
+		upgradeEnd := upgrade.Height + upgradeBoundary
+
+		s.upgrades = append(s.upgrades, upgradeRange{start: upgradeStart, end: upgradeEnd})
+	}
+
 	// should we warmup
 	warmup := false
 
diff --git a/blockstore/splitstore/splitstore_compact.go b/blockstore/splitstore/splitstore_compact.go
index 4ff38a5fb..3a1fda202 100644
--- a/blockstore/splitstore/splitstore_compact.go
+++ b/blockstore/splitstore/splitstore_compact.go
@@ -99,6 +99,12 @@ func (s *SplitStore) HeadChange(_, apply []*types.TipSet) error {
 		return nil
 	}
 
+	if s.isNearUpgrade(epoch) {
+		// we are near an upgrade epoch, supress compaction
+		atomic.StoreInt32(&s.compacting, 0)
+		return nil
+	}
+
 	if epoch-s.baseEpoch > CompactionThreshold {
 		// it's time to compact -- prepare the transaction and go!
 		s.beginTxnProtect()
@@ -121,6 +127,16 @@ func (s *SplitStore) HeadChange(_, apply []*types.TipSet) error {
 	return nil
 }
 
+func (s *SplitStore) isNearUpgrade(epoch abi.ChainEpoch) bool {
+	for _, upgrade := range s.upgrades {
+		if epoch >= upgrade.start && epoch <= upgrade.end {
+			return true
+		}
+	}
+
+	return false
+}
+
 // transactionally protect incoming tipsets
 func (s *SplitStore) protectTipSets(apply []*types.TipSet) {
 	s.txnLk.RLock()