If you need to run software/servers with any kind of data consistency/reliability on OS X this is definitely something you should be aware of and will be a footgun if you're used to Linux.

Macs in datacentres are becoming increasingly common for CI, MDM, etc.

I’d rather solve for redundant power than worry about this. It’s really only critical if you’re running a database. Who runs a database on macOS?

Every single iOS app using Core Data (which runs SQLite under the hood)

People doing CI? Or MDM?

Not sure how either of those would be critically impacted by a 1-2 second data loss in a power failure.

I believe it’s at least 5s. Marcan didn’t specify how long it was, but gave an example of at least 5s. That could cause a device to think it’s allowed to do something via MDM but not actually have a record in the database allowing it to do so.

You don't just lose seconds of data. When you drop seconds of writes, that can effectively corrupt any data or metadata that was touched during that time period. Which means you can lose data that had been safe.

> CI

Perhaps.

> MDM

I’m sure my IT department’s spyware will recover just fine.

The OS itself contains hundreds of databases.

And with those hundreds of databases, we’re only learning about this behavior now instead of any of the previous decades where abundant errors would have caused a conversation.

Doesn’t seem like an issue worthy of hundreds of HN comments and upvotes, just people raising a stink over a non-issue.

If in a hundred times someone loses power, their system is corrupted once, it’s a choice whether you accept that or not. I do not. I want quality and quality is an system that does not get corrupted.

I've used Macs for years and never been aware of it.

Note: the tweeter couldn't provoke actual problems under any sort of normal usage. To make data loss show up he had to use weird USB hacks. If you know you have a battery and can forcibly shut down the machine 'cleanly' it's not really clear what the need for a hard fsync is.

"Macs in datacentres are becoming increasingly common for CI, MDM, etc."

CI machines are the definition of disposable data. Nobody is running Oracle on macOS and Apple don't care about that market.

These days, best practice for data consistency / reliability in that environment, IIUC, is to write to multiple redundant shards and checksum, not to assume any particular field-pattern spat at the hard drive will make for a reliability guarantee.

"never encountered any problems whatsoever?"

And how do you know they didn't, did you do a poll?

How many people had random files dissapear or get corrupted or settings get reset and probzbly thought they must have done something wrong?