- if err := v.os.Rename(tmpfile.Name(), bpath); err != nil {
- err = fmt.Errorf("error renaming %s to %s: %s", tmpfile.Name(), bpath, err)
- v.os.Remove(tmpfile.Name())
- return err
+ // ext4 uses a low-precision clock and effectively backdates
+ // files by up to 10 ms, sometimes across a 1-second boundary,
+ // which produces confusing results in logs and tests. We
+ // avoid this by setting the output file's timestamps
+ // explicitly, using a higher resolution clock.
+ ts := time.Now()
+ v.os.stats.TickOps("utimes")
+ v.os.stats.Tick(&v.os.stats.UtimesOps)
+ if err = os.Chtimes(tmpfile.Name(), ts, ts); err != nil {
+ return fmt.Errorf("error setting timestamps on %s: %s", tmpfile.Name(), err)
+ }
+ if err = v.os.Rename(tmpfile.Name(), bpath); err != nil {
+ return fmt.Errorf("error renaming %s to %s: %s", tmpfile.Name(), bpath, err)