feat: enhance logging and performance metrics for migration processes

cmd/go_migrate/loader.go

@@ -3,6 +3,7 @@ package main
 import (
 	"context"
 	"fmt"
+	"time"
 
 	"github.com/jackc/pgx/v5"
 	"github.com/jackc/pgx/v5/pgxpool"
@@ -22,12 +23,17 @@ func fakeLoader(job MigrationJob, columns []ColumnType, in <-chan [][]any) {
 }
 
 func loadRowsPostgres(ctx context.Context, job MigrationJob, columns []ColumnType, db *pgxpool.Pool, in <-chan []UnknownRowValues) error {
+	chunkCount := 0
+	totalRowsLoaded := 0
+
 	for rows := range in {
+		chunkStartTime := time.Now()
 		identifier := pgx.Identifier{job.Schema, job.Table}
 		colNames := Map(columns, func(col ColumnType) string {
 			return col.name
 		})
 
+		copyStartTime := time.Now()
 		_, err := db.CopyFrom(
 			ctx,
 			identifier,
@@ -38,6 +44,15 @@ func loadRowsPostgres(ctx context.Context, job MigrationJob, columns []ColumnTyp
 		if err != nil {
 			return err
 		}
+
+		chunkCount++
+		totalRowsLoaded += len(rows)
+		copyDuration := time.Since(copyStartTime)
+		chunkDuration := time.Since(chunkStartTime)
+		rowsPerSec := float64(len(rows)) / chunkDuration.Seconds()
+
+		log.Infof("Loaded chunk #%d: %d rows in %v (copy: %v, %.0f rows/sec) - Total: %d rows",
+			chunkCount, len(rows), chunkDuration, copyDuration, rowsPerSec, totalRowsLoaded)
 	}
 
 	return nil