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I've 100% had issues with UFS, it's a simple filesystem and subsceptible to corruption. ZFS meanwhile is a different beast altogether which is designed to ensur

I've 100% had issues with UFS, it's a simple filesystem and subsceptible to corruption. ZFS meanwhile is a different beast altogether which is designed to ensure data integrity at all costs.

adrian_b 3y ago
UFS without soft updates is easily susceptible to corruption. The "soft updates" option must be chosen when the disk is formatted for good reliability. As I have said, 20 years ago "soft updates" in UFS worked better than journaling in the other contemporaneous file systems. Nowadays it is likely that this is no longer true. I am still using FreeBSD in servers, but unlike 20 years ago I can afford UPSes so I no longer see often crashes due to power outages, even if I had one incident some time ago with a battery that had not been replaced yet after the UPS had warned that this is necessary, and when a power outage happened, the UPS worked for less than a minute and the power was cut before system shutdown. Even in this case there was no file system corruption on UFS. Even with this good recent experience, today I would no longer trust UFS like 20 years ago, because it is said the current FreeBSD maintainers no longer understand the convoluted code that implements "soft updates" in UFS, and in any case most of their file system maintenance and development work is directed at ZFS now.
- throw0101d 3y ago
  A journal(-like) mechanism was added to soft-upates by McKusick in the 2010 timeframe: * https://www.youtube.com/watch?v=_NuhRkiInvA https://www.youtube.com/watch?v=_NuhRkiInvA (BSDCan) * https://www.mckusick.com/softdep/suj.pdf https://www.mckusick.com/softdep/suj.pdf Which also allows snapshots: * https://freebsdfoundation.org/project/snapshots-on-filesystems-using-journaled-soft-updates/ https://freebsdfoundation.org/project/snapshots-on-filesyste... See also "Journaling versus Soft Updates: Asynchronous Meta-data Protection in File Systems": * https://www.seltzer.com/assets/publications/Journaling-versus-Soft-Updates-Asynchronous-Metadata-Protection-in-File-Systems.html https://www.seltzer.com/assets/publications/Journaling-versu...
- tiffanyh 3y ago
  OpenBSD recently decided to turn OFF soft update, by default. https://undeadly.org/cgi?action=article;sid=20230706044554 https://undeadly.org/cgi?action=article;sid=20230706044554
  - ptx 3y ago
    Although, according to the link, not because there's anything wrong with it, but because other changes they want to make to the filesystem code would risk breaking soft updates.
  - sillywalk 3y ago
    FTA: Log message: Make softdep mounts a no-op Softdep is a significant impediment to progressing in the vfs layer so we plan to get it out of the way. It is too clever for us to continue maintaining as it is.
- clausecker 3y ago
  UFS on FreeBSD is still maintained bz Kirk McKusick, the inventor of soft updates. It's the other BSDs that have trouble as they can't rely on Kirk's expertise.
hulitu 3y ago
ZFS had its own data corruption bug some months ago. TBH, this was a big minus. You really don't expect such things from a filesystem which is in production for years and whos aim is data integrity. Now, to its defence, it is only used by FreeBSD and some nishe linux distributions, so it does not get much testing.
- abrookewood 3y ago
  Well maybe you missed the news about the bug in EXT4 ... https://news.ycombinator.com/item?id=38585189 https://news.ycombinator.com/item?id=38585189

I've 100% had issues with UFS, it's a simple filesystem and subsceptible to corruption. ZFS meanwhile is a different beast altogether which is designed to ensure data integrity at all costs.

adrian_b 3y ago

UFS without soft updates is easily susceptible to corruption. The "soft updates" option must be chosen when the disk is formatted for good reliability. As I have said, 20 years ago "soft updates" in UFS worked better than journaling in the other contemporaneous file systems. Nowadays it is likely that this is no longer true. I am still using FreeBSD in servers, but unlike 20 years ago I can afford UPSes so I no longer see often crashes due to power outages, even if I had one incident some time ago with a battery that had not been replaced yet after the UPS had warned that this is necessary, and when a power outage happened, the UPS worked for less than a minute and the power was cut before system shutdown. Even in this case there was no file system corruption on UFS. Even with this good recent experience, today I would no longer trust UFS like 20 years ago, because it is said the current FreeBSD maintainers no longer understand the convoluted code that implements "soft updates" in UFS, and in any case most of their file system maintenance and development work is directed at ZFS now.

throw0101d 3y ago
A journal(-like) mechanism was added to soft-upates by McKusick in the 2010 timeframe: * https://www.youtube.com/watch?v=_NuhRkiInvA https://www.youtube.com/watch?v=_NuhRkiInvA (BSDCan) * https://www.mckusick.com/softdep/suj.pdf https://www.mckusick.com/softdep/suj.pdf Which also allows snapshots: * https://freebsdfoundation.org/project/snapshots-on-filesystems-using-journaled-soft-updates/ https://freebsdfoundation.org/project/snapshots-on-filesyste... See also "Journaling versus Soft Updates: Asynchronous Meta-data Protection in File Systems": * https://www.seltzer.com/assets/publications/Journaling-versus-Soft-Updates-Asynchronous-Metadata-Protection-in-File-Systems.html https://www.seltzer.com/assets/publications/Journaling-versu...
tiffanyh 3y ago
OpenBSD recently decided to turn OFF soft update, by default. https://undeadly.org/cgi?action=article;sid=20230706044554 https://undeadly.org/cgi?action=article;sid=20230706044554
- ptx 3y ago
  Although, according to the link, not because there's anything wrong with it, but because other changes they want to make to the filesystem code would risk breaking soft updates.
- sillywalk 3y ago
  FTA: Log message: Make softdep mounts a no-op Softdep is a significant impediment to progressing in the vfs layer so we plan to get it out of the way. It is too clever for us to continue maintaining as it is.
clausecker 3y ago
UFS on FreeBSD is still maintained bz Kirk McKusick, the inventor of soft updates. It's the other BSDs that have trouble as they can't rely on Kirk's expertise.

hulitu 3y ago

ZFS had its own data corruption bug some months ago. TBH, this was a big minus. You really don't expect such things from a filesystem which is in production for years and whos aim is data integrity. Now, to its defence, it is only used by FreeBSD and some nishe linux distributions, so it does not get much testing.

abrookewood 3y ago
Well maybe you missed the news about the bug in EXT4 ... https://news.ycombinator.com/item?id=38585189 https://news.ycombinator.com/item?id=38585189