Stefan writes: > I seem to remember, that drives of that time required the write cache > to be enabled to get any speed-up from tagged commands. This was no > risk with SCSI drives, since the cache did not make the drives lye > about command completion (i.e. the status for the write was only > returned when the cached data had been written to disk, independently > of the write cache enable).
Interesting. Is there a way to tell, other than coming up with some way to actually test it, whether a particular drive waits until the data has been written to non-volatile memory (the platters in conventional disks) before sending the command completion message? I'm having thoughts of putting sensing resistors in the disk's power cable, attaching an oscilloscope, and displaying the timing of data on the data cable along with power usage from seeking. _______________________________________________ freebsd-hackers@freebsd.org mailing list http://lists.freebsd.org/mailman/listinfo/freebsd-hackers To unsubscribe, send any mail to "freebsd-hackers-unsubscr...@freebsd.org"
