Re: Disk write cache (Was: Hyper-Threading Vulnerability)

Alan Cox
2005-05-16T14:58:36Z

> I have heard rumors about this, but all OEM manuals I looked at for
> drives I bought or recommended simply stated that the block currently
> being written at power loss can become damaged (with write cache off),
> and that the drive can lose the full write cache at power loss (with
> write cache on) so this looks like daydreaming manifested as rumor.

IBM drives definitely used to trash the sector in this case. They newer
ones either don't or recover from it presumably because people took that
to be a drive failure and returned it. Sometimes the people win ;)

> flashes its cache to NVRAM, or uses rotational energy to save its cache
> on the platters, please name brand and model and where I can download
> the material that documents this behavior.

I am not aware of any IDE drive with these properties.