Messages in this thread | | | Date | Thu, 5 Oct 2023 10:10:45 -0700 | Subject | Re: [PATCH 10/21] block: Add fops atomic write support | From | Bart Van Assche <> |
| |
On 10/4/23 11:17, Martin K. Petersen wrote: > > Hi Bart! > >> In other words, also for the above example it is guaranteed that >> writes of a single logical block (512 bytes) are atomic, no matter >> what value is reported as the ATOMIC TRANSFER LENGTH GRANULARITY. > > There is no formal guarantee that a disk drive sector > read-modify-write operation results in a readable sector after a > power failure. We have definitely seen blocks being mangled in the > field.
Aren't block devices expected to use a capacitor that provides enough power to handle power failures cleanly?
How about blacklisting block devices that mangle blocks if a power failure occurs? I think such block devices are not compatible with journaling filesystems nor with log-structured filesystems.
Thanks,
Bart.
| |