> > While I don't have the relevant hardware, this sounds like a hardware > limitation, not a regression. I suspect that the LED is active whenever > a command is outstanding; with NCQ allowed to queue more than 1 command > at a time, Linux is keeping the drive fed with commands so that there > are always outstanding commands, and thus the light never goes inactive > during disk activity. > > As a result, you never see the LED intensity vary, as the drive never > idles waiting for a new command, but is constantly processing commands > as fast as it can. Allowing the drive to idle would get you the > "flickering" you want, at the expense of the performance gain NCQ > provides. Frans reported that the LED stays on during disk activity, so it looks like the drive always unbusy. I need to check with the HW guys how the activity LED behaves in NCQ mode. I suspect that this disk responds immediately to new commands telling the host "I got the command and it will be handled later", this response clears the ports ATA busy bit. If the activity LED reflects only the state of that bit in NCQ mode, then that could explain the behavior that Frans described. - saeed -- To unsubscribe from this list: send the line "unsubscribe linux-ide" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
