In Windows 7, using the Device Manager, bringing up the properties of a disk, and going to the Policies tab, there are 2 switch items. The write cache, which this question it not about.
[X] Turn off Windows write-cache buffer flushing on the device <--- this one only!
Microsoft puts a disclaimer on the tab for that item. "To prevent data loss, do not select this checkbox unless the device has a separate power supply that allows the device to flush its buffer in case of a power loss."
In simple terms , what does this change for file writing, file saving, file copying?
1. Changing write actions for paranoid programs: (fact or fiction)
Does it change the way write flushes work for a program that Forces a cache flush to occur? Some programs are very intent on finishing the write, without speculating, are these programs able to continue thier protective writing, or does this change for those programs also?
2. Types of programs effected:
What are the types of actions/programs that would or would not be efffected by the change? Type, some programs stream, some do quick write outs, some are continuous, some are protective (or any other type you could define in simple terms).
3. Did You see anything, or a benchmark even:
If the setting is on, what are the observable changes in writing? Any loose examples of an observed change in behavior. or observed no change in behavior?
4. What is the holdup or delay :
We know most of these actions are very fast on most computers, The data will eventualy be written. Relative to the the speed of the drive, is the ammount of time significant?
For the purposes of my question, the risk that exists is not one of the questions, if you would like to cover it , it would not get in the way.
What does "Write cache buffer flushing" mean is almost a dupe of this, but the link is for a different OS. Although the A has some info , even the term used in the link is not the same. It also does not answer the most significant things that a user would want to know, that I have tried to outline here.