
The "fsync" level already flushes drive write caches on Windows (as does "fdatasync"), so it only confuses matters to have an apparently higher level that isn't actually different at all. That leaves "fsync_writethrough" only for macOS, where it actually does something different. Reviewed-by: Magnus Hagander <magnus@hagander.net> Discussion: https://postgr.es/m/CA%2BhUKGJ2CG2SouPv2mca2WCTOJxYumvBARRcKPraFMB6GSEMcA%40mail.gmail.com