resumabble pg-fill

cmd/pg-fill/main.go

@@ -29,15 +29,17 @@ func run(ctx context.Context) error {
 	}
 
 	return with.PSQL(ctx, *c, func(pg *sql.DB) error {
-		report := func() error {
-			var n2 uint64
+		presently := func() int {
+			var n2 int
 			if row := pg.QueryRowContext(ctx, `SELECT pg_total_relation_size('fill_with_data')/1024/1024`); row.Err() != nil {
-				return row.Err()
+				return 0
 			} else if err := row.Scan(&n2); err != nil {
-				return err
+				return 0
 			}
-			log.Printf("filled %vMiB of requested %vMiB", n2, *n)
-			return nil
+			return n2
+		}
+		report := func() {
+			log.Printf("filled %vMiB of requested %vMiB", presently(), *n)
 		}
 
 		go with.Every(ctx, 5*time.Second, func() {
@@ -53,7 +55,7 @@ func run(ctx context.Context) error {
 
 		// https://gist.github.com/ololobus/5b25c432f208d7eb31051a5f238dffff
 		// 2e6=1GB, so 2e6/8=12MB
-		for i := 0; i < (*n)/12; i++ {
+		for i := presently(); i < (*n)/12; i++ {
 			for ctx.Err() == nil {
 				if _, err := pg.ExecContext(ctx, `
 			   	INSERT INTO fill_with_data (x, y, z)
@@ -72,6 +74,7 @@ func run(ctx context.Context) error {
 			}
 		}
 
-		return report()
+		report()
+		return nil
 	})
 }