Safe Windows hibernation on completing a sync

[Alan1951]

I keep an external HDD connected to my Windows 10 machine and use FFS to back up to it and then hibernate the machine on completion.

I have read that shutdown would be safer because there is some risk of Windows failing to recognise my drive as external, so that Windows does not flush its system file cache to the drive before hibernating, which could lead to a severe problem under certain circumstances.

I'm not aware that this has ever happened to me, but I understand that a Windows application can request Windows to flush its write operations to disk immediately.

Can anyone confirm that FFS requests Windows to do this before completing a synchronisation?

If I've understood correctly, disk write caching is another layer of caching that operates on a drive's internal cache under the control of its firmware. If so, would disabling "write caching on the disk" in the external drive's properties in Device Manager make backup even more resilient, at the cost of lower write speed?

[Alan1951]

My question is irrelevant, as the default removal policy for any external drive in its Device Manager properties is Quick Removal, which "Disables write caching on the device and in Windows", so I will simply stick with that.

[xCSxXenon]

That is the default, yes. That is why you can't "eject" external drives usually. USB sticks are different though, but ejecting is mainly a way to see if the drive is still in use rather than ejecting.

[Alan1951]

Thank you, xCSxXenon! That all makes sense. :)