SOLVED USB boot drive - performance penalty? What are the disadvantages?

[flashdrive]

I am using a 3 mirror USB boot drive setup.

I have read that the system pool is being transfered to the first data pool of the system.

What is the benefit of having an SSD boot device in terms of network transfer speed?

What kind of data is being constantly written to the boot drive?

My goal is to check if the USB boot drive is somewhat of a bottleneck.

 

[sretalla]

What is the benefit of having an SSD boot device in terms of network transfer speed?

If you're transferring data that's on the boot pool... some. Otherwise, none.

What kind of data is being constantly written to the boot drive?

Not much if you have left the system dataset on your data pool as will automatically have been moved there... with an SSD, it would be fine to move it back there, but don't do that with USB.

My goal is to check if the USB boot drive is somewhat of a bottleneck.

Unlikely. You can look at the reports and see if it's being overworked, but that would be something specific to your system as I've never seen it be the case.

 

[danb35]

I have read that the system pool is being transfered to the first data pool of the system.

The .system dataset starts on the boot pool, and is moved to the first data pool when that pool is created. It then stays there, unless you move it through the GUI. It's been that way for a long time--I can't say exactly how long, but early into the 11.x series at least. Unless you've moved .system back to the boot pool, there wouldn't be any regular data transfer to or from that pool. and the large majority of what's on it (what's being used, anyway) is going to live in RAM.

The only place where boot pool performance is going to affect performance is (1) when booting the system, (2) when installing an upgrade, and (3) when making changes to system settings (as the config database lives on the boot pool).

 

[flashdrive]

Thank you @sretalla and @danb35 for your insights.

I will stick with the USB boot pool then.