From a4218cd6f416c9448298c219fdac442bd82961ec Mon Sep 17 00:00:00 2001
From: Cathal Coffey <coffey.cathal@gmail.com>
Date: Sun, 31 Jan 2021 18:27:34 +0000
Subject: [PATCH] Progress should print HeartbeatLag

---
 doc/hooks.md         | 1 +
 go/base/context.go   | 4 ++++
 go/logic/hooks.go    | 1 +
 go/logic/migrator.go | 3 ++-
 4 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/doc/hooks.md b/doc/hooks.md
index 4c49c85..91e1311 100644
--- a/doc/hooks.md
+++ b/doc/hooks.md
@@ -66,6 +66,7 @@ The following variables are available on all hooks:
 - `GH_OST_ESTIMATED_ROWS` - estimated total rows in table
 - `GH_OST_COPIED_ROWS` - number of rows copied by `gh-ost`
 - `GH_OST_INSPECTED_LAG` - lag in seconds (floating point) of inspected server
+- `GH_OST_HEARTBEAT_LAG` - lag in seconds (floating point) of heartbeat
 - `GH_OST_PROGRESS` - progress pct ([0..100], floating point) of migration
 - `GH_OST_MIGRATED_HOST`
 - `GH_OST_INSPECTED_HOST`
diff --git a/go/base/context.go b/go/base/context.go
index 3026dc5..cc8e9cc 100644
--- a/go/base/context.go
+++ b/go/base/context.go
@@ -455,6 +455,10 @@ func (this *MigrationContext) MarkRowCopyEndTime() {
 	this.RowCopyEndTime = time.Now()
 }
 
+func (this *MigrationContext) GetCurrentHeartbeatLagDuration() time.Duration {
+	return time.Duration(atomic.LoadInt64(&this.CurrentHeartbeatLag))
+}
+
 func (this *MigrationContext) GetCurrentLagDuration() time.Duration {
 	return time.Duration(atomic.LoadInt64(&this.CurrentLag))
 }
diff --git a/go/logic/hooks.go b/go/logic/hooks.go
index fa5011e..9f119be 100644
--- a/go/logic/hooks.go
+++ b/go/logic/hooks.go
@@ -64,6 +64,7 @@ func (this *HooksExecutor) applyEnvironmentVariables(extraVariables ...string) [
 	env = append(env, fmt.Sprintf("GH_OST_INSPECTED_HOST=%s", this.migrationContext.GetInspectorHostname()))
 	env = append(env, fmt.Sprintf("GH_OST_EXECUTING_HOST=%s", this.migrationContext.Hostname))
 	env = append(env, fmt.Sprintf("GH_OST_INSPECTED_LAG=%f", this.migrationContext.GetCurrentLagDuration().Seconds()))
+	env = append(env, fmt.Sprintf("GH_OST_HEARTBEAT_LAG=%f", this.migrationContext.GetCurrentHeartbeatLagDuration().Seconds()))
 	env = append(env, fmt.Sprintf("GH_OST_PROGRESS=%f", this.migrationContext.GetProgressPct()))
 	env = append(env, fmt.Sprintf("GH_OST_HOOKS_HINT=%s", this.migrationContext.HooksHintMessage))
 	env = append(env, fmt.Sprintf("GH_OST_HOOKS_HINT_OWNER=%s", this.migrationContext.HooksHintOwner))
diff --git a/go/logic/migrator.go b/go/logic/migrator.go
index 83e4228..aae3cb3 100644
--- a/go/logic/migrator.go
+++ b/go/logic/migrator.go
@@ -980,13 +980,14 @@ func (this *Migrator) printStatus(rule PrintStatusRule, writers ...io.Writer) {
 
 	currentBinlogCoordinates := *this.eventsStreamer.GetCurrentBinlogCoordinates()
 
-	status := fmt.Sprintf("Copy: %d/%d %.1f%%; Applied: %d; Backlog: %d/%d; Time: %+v(total), %+v(copy); streamer: %+v; Lag: %.2fs, State: %s; ETA: %s",
+	status := fmt.Sprintf("Copy: %d/%d %.1f%%; Applied: %d; Backlog: %d/%d; Time: %+v(total), %+v(copy); streamer: %+v; Lag: %.2fs, HeartbeatLag: %.2fs, State: %s; ETA: %s",
 		totalRowsCopied, rowsEstimate, progressPct,
 		atomic.LoadInt64(&this.migrationContext.TotalDMLEventsApplied),
 		len(this.applyEventsQueue), cap(this.applyEventsQueue),
 		base.PrettifyDurationOutput(elapsedTime), base.PrettifyDurationOutput(this.migrationContext.ElapsedRowCopyTime()),
 		currentBinlogCoordinates,
 		this.migrationContext.GetCurrentLagDuration().Seconds(),
+		this.migrationContext.GetCurrentHeartbeatLagDuration().Seconds(),
 		state,
 		eta,
 	)