OpenZFS on OS X

From reading the man page on zpool I understand that it's not possible to start two scrubs and have them run simultaneous.

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Because scrubbing and resilvering are I/O-intensive operations, ZFS only allows one  at  a  time.
If  a  scrub  is already  in progress, the "zpool scrub" command terminates it and starts a new scrub.

Maybe this is stupid but unless potentially disastrous it would make sense to me to scrub both my pools at the same time.
If the reason is not technical but only about system load and performance, is there any way of forcing two simultaneous scrubs?

I routinely scrub 3 pools at the same time no issues on a lowly code duo e8400 with 8gb ram. 2 12tb pools and a 4tb pool. Some on sata sockets, some on 1068 and one 8drive pool on 1x pcie seats card.

Ok, I guess if that's the case then the man page doesn't reflect the actual functionality.
It says when a scrub is started it will automatically stop any other scrub.
Well, I'll give it a go..

RobRehnmark wrote:Ok, I guess if that's the case then the man page doesn't reflect the actual functionality.
It says when a scrub is started it will automatically stop any other scrub.
Well, I'll give it a go..

I believe, it is meant for "scrubbing the same pool". If you start a scrub for poolA, then forget that you did and try to start a scrub for the same poolA again, it will automatically cancel the on-going scrub and start the new one.

Tip wrote:

RobRehnmark wrote:Ok, I guess if that's the case then the man page doesn't reflect the actual functionality.
It says when a scrub is started it will automatically stop any other scrub.
Well, I'll give it a go..

I believe, it is meant for "scrubbing the same pool". If you start a scrub for poolA, then forget that you did and try to start a scrub for the same poolA again, it will automatically cancel the on-going scrub and start the new one.

Yes, it seems so.
Maybe that could be clarified in the man page?
As it is now it's not technically correct.