Power protected SLOGs... Great. But what about power protected SATA controller?

[SwisherSweet]

If a SLOG has power protection, does that mean that any data in the SSD's buffer that wasn't writen to durable storage when the card lost power would be written using power backup?

What about data that is stuck in the SATA controller's buffer, assuming it has one? Wouldn't that data be lost? If a SATA controller buffers data prior to shipping it to the SATA disk, there's still a change to loose data during sudden power loss, right?

 

[Ericloewe]

The difference is that the HBA doesn't tell the OS that a write has been finished. Or it shouldn't - RAID controllers may do that, hence why they have backup batteries.