Miles Nordin wrote:
Since this discussion is taking place in the context of someone removing a USB stick I think you're confusing the issue by dragging in other technologies. Let's keep this in the context of the posts preceding it which is how USB devices are treated. I would argue that one of the first design goals in an environment where you can expect people who are not computer professionals to be interfacing with computers is to make sure that the appropriate safeties are in place and that the system does not behave in a manner which a reasonable person might find unexpected.gm> That implies that ZFS will have to detect removable devices gm> and treat them differently than fixed devices.please, no more of this garbage, no more hidden unchangeable automatic condescending behavior. The whole format vs rmformat mess is just ridiculous. And software and hardware developers alike have both proven themselves incapable of settling on a definition of ``removeable'' that fits with actual use-cases like: FC/iSCSI; hot-swappable SATA; adapters that have removeable sockets on both ends like USB-to-SD, firewire CD-ROM's, SATA/SAS port multipliers, and so on.
This is common practice for any sort of professional engineering effort. As an example, you aren't going to go out there and find yourself a chainsaw being sold new without a guard. It might be removable, but the default is to include it. Why? Well because there is a considerable chance of damage to the user without it. Likewise with a file system on a device which might cache a data write for as long as thirty seconds while being easily removable. In this case, the user may write the file and seconds later remove the device. Many folks out there behave in this manner.
It really doesn't matter to them that they have a copy of the last save they did two hours ago, what they want and expect is that the most recent data they saved actually be on the USB stick for the to retrieve. What you are suggesting is that it is better to lose that data when it could have been avoided. I would personally suggest that it is better to have default behavior which is not surprising along with more advanced behavior for those who have bothered to read the manual. In Windows case, the write cache can be turned on, it is not "unchangeable" and those who have educated themselves use it. I seldom turn it on unless I'm doing heavy I/O to a USB hard drive, otherwise the performance difference is just not that great.
Regards, Greg _______________________________________________ zfs-discuss mailing list zfs-discuss@opensolaris.org http://mail.opensolaris.org/mailman/listinfo/zfs-discuss
