Running default in Target Mode

[Pyriphlegethon]

Would there be a performance hit to running a 2017 iMac from my MBP set in target disk mode? I prefer only having to keep apps and their settings, preferences, updates, plugins, etc maintained on a single machine, in this case the MBP. I'm hoping to use my MBP as my primary machine and then plug the iMac into it so I get the same user experience when on the iMac but with access to more powerful iMac hardware when the iMac is available to me.

This may seem odd, but I've been tracking my time and I lose an incredible amount of efficiency due to having to maintain two different setups.

 

[trsblader]

EDIT: misread OP

 

[Pyriphlegethon]

2017 iMacs do not support target display mode. According to Apple documents, the last iMacs to support this were 2014 models.

Wait, you're referring to "target display mode". I'm referring to "target disk mode". Two different things, right?

 

[trsblader]

Wait, you're referring to "target display mode". I'm referring to "target disk mode". Two different things, right?

...and that’s why you don’t reply to threads first thing in the morning. That one’s on me.

 

[Pyriphlegethon]

...and that’s why you don’t reply to threads first thing in the morning. That one’s on me.

No worries. I appreciate the fact that you responded. I think my best bet might just be to test target mode vs booting from an external disk vs internal startup disk and just see if performance is affected for the things I'd need it for. The reality is that I haven't yet bought the iMac or Mac Pro I intend to try this setup with so I think I'll just have to buy, test and return if it doesn't work. I'm still on the old 2010 Mac which doesn't lend to testing performance of an external startup disk with its high speed FW800 ports...

I should note, that, testing this on an older iMac and my 2014 MBP, a disk speed test of the MBP drive is much faster when run natively than when run from the iMac using the MBP in target disk mode. Not looking promising.

 

[redheeler]

No worries. I appreciate the fact that you responded. I think my best bet might just be to test target mode vs booting from an external disk vs internal startup disk and just see if performance is affected for the things I'd need it for. The reality is that I haven't yet bought the iMac or Mac Pro I intend to try this setup with so I think I'll just have to buy, test and return if it doesn't work. I'm still on the old 2010 Mac which doesn't lend to testing performance of an external startup disk with its high speed FW800 ports...

I should note, that, testing this on an older iMac and my 2014 MBP, a disk speed test of the MBP drive is much faster when run natively than when run from the iMac using the MBP in target disk mode. Not looking promising.

Connecting the 2014 MacBook Pro to a newer iMac via Thunderbolt 2 should result in comparable performance with much less of a bottleneck, but over the old FireWire 800 connection found on your 2010 iMac it is severely bottlenecked compared to its native performance. However, keep in mind that the SSDs in the newer SSD-only iMacs are faster the one in your 2014 MacBook Pro, so regardless you will lose out on some performance when buying a new iMac or iMac Pro with SSD-only storage and using the 2014 MacBook Pro in Target Disk Mode instead of the iMac's built-in SSD.

Should also add that I recommend waiting until after WWDC before buying a new iMac, as it is possible the new 2018 models will be announced.

 

[Pyriphlegethon]

Connecting the 2014 MacBook Pro to a newer iMac via Thunderbolt 2 should result in comparable performance with much less of a bottleneck, but over the old FireWire 800 connection found on your 2010 iMac it is severely bottlenecked compared to its native performance. However, keep in mind that the SSDs in the newer SSD-only iMacs are faster the one in your 2014 MacBook Pro, so regardless you will lose out on some performance when buying a new iMac or iMac Pro with SSD-only storage and using the 2014 MacBook Pro in Target Disk Mode instead of the iMac's built-in SSD.

Should also add that I recommend waiting until after WWDC before buying a new iMac, as it is possible the new 2018 models will be announced.

Thanks for your reply. I do understand that a new iMac's SSD runs at theoretically higher speeds than older non-SSD drives. The peculiar thing is that, like I mentioned, when I speed test my MBP's internal startup drive on its own I get very good speed, but when testing that exact same drive from the iMac (MBP in target disk mode) the speed drops enormously. I can't figure out why.

Using the FW800 Mac Pro was a joke And I do plan to wait until next month to upgrade. If Apple introduces a non-expandable Mac "pro" available in two years and running on ARM I may be done with the company anyway. But fingers crossed for a real Mac Pro and a laptop with more than 16GB of RAM!