On Tue, 2014-08-12 at 07:55 +0200, Can Jeuleers wrote: > On 08/12/2014 03:21 AM, Larkin Lowrey wrote: > > Also, leaving spin-up to the controller is > > also not so hot since some controllers spin-up the drives sequentially > > rather than in parallel. > > Sequential spin-up is a feature to some, because it avoids large power > spikes. I vaguely recall older drives had a jumper to set a delayed spin up so they stayed in a low power (possibly un-spun up) mode when power was applied and only woke up when a command was received (I think any command, not a specific "wake up" one). Also as mentioned some controllers may also only wake drives one after the other, likewise mdriad does not care about the underlying hardware/driver stack, only that it eventually responds, and even then I believe it will happily wait till the end of time if no response or error is propagated up the stack; hence the time out in scsi_device stack not in the mdraid. > -- > To unsubscribe from this list: send the line "unsubscribe linux-raid" in > the body of a message to majordomo@xxxxxxxxxxxxxxx > More majordomo info at http://vger.kernel.org/majordomo-info.html > -- To unsubscribe from this list: send the line "unsubscribe linux-raid" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
