Originally Posted by Marvin
It's not like people will daisy-chain 7 devices off each port if they have 6 ports - who even daisy chains 2 devices? If you have 32Gbps/6 = 5Gbps per port, you can easily have say 3 x 30" displays, a capture card and a RAID array connected. If people go overboard with it, the devices just won't have enough bandwidth but it's their own fault and they just unplug something. Also, it can be hooked into a PCI 3.0 slot.
I think it will be the end for multiple internal expansion slots, especially when it hits 100Gbps (or when you get multiple ports from a 100Gbps+ source). Computer technology just has to match usage scenarios and examples saturating 100Gbps are going to be pretty flakey.
People won't have 6 TB ports in the near future. What can be hooked to what PCIe 3.0 slot? So now it's TB ports and PCIe slots on the same computer? So the MP isn't dead yet?
Wow. Still not getting it. Let's talk about today or this year or even early next year, Thunderbolt at 10Gb/s, because you won't see 100Gb/s Light Peak before 2020 (that's Intel's own forecast), and you don't know when TB will move to v2 either. Those bi-directional 10Gb/s channels don't appear for thin air, but from the PCIe lanes available on the cpu/chipset of the computer.
For the next few months we will see only one Thunderbolt port on computers, two on very few designs.
- Because each TB port uses 4x PCIe 2.0 lanes.
How many PCIe 2.0 lanes found on mainstream cpus?
What about if I want a dedicated gpu connected to the cpu?
1- no Thunderbolt.
2- TB on the chipset that already uses some PCIe lanes for other tasks and a slower link to the cpu, performance will be poor.
3- use 8x for the gpu and up to 8x for TB controller(s), that's what Apple did for the 15/17" MBPs
So, for the next few months people will only have one TB port to play with, they will daisy chain a lot. A typical setup in audio will be:
MacBook Pro - Storage - audio interface - DSP processing - display (optional, but nice to have)
That's what you will see in most digital audio workstations like the MP, but internally. Typically, you'll have multiple drives, the gpu, one i/o card and up to 2 DSP cards (Apogee + UAD-2, for example), or up to three combo i/o-DSP cards (Pro Tools HD).
And that's already something you can often see with FW: multiple storage units + audio interface, even sometimes a FW DSP unit (there are few of them, but they exist).
I don't except the iMac to get more than one TB port either, it has the same limitations as the MBP. The only design that could receive two TB controllers/ports is the Mac mini server (integrated graphics, two display outputs and HDMI useless, 16x unused PCIe lanes on the cpu to play with). So daisy-chaining will be very common.
Just try to realize that 6 TB ports mean 24x PCIe 2.0 lanes used (just for data, not including PCIe lanes for the gpus). Only Xeon and very high-end desktop cpus offer that many lanes. For you that means that only workstations/servers/very high-end desktop will be able to offer that many TB ports. So they compete with themselves?
When/If, one day, there are enough Thunderbolt devices (in a wide price range) to make FW really obsolete, then we will probably get 2 TB ports on MBPs, iMacs,... But it will take some time.
When, one day, TB reaches v2 (20Gb/s), it will also need 2 times the number of lanes (or lanes twice as fast), so the problem will be similar (how many lanes on the cpu, how many for the gpu,...). Intel will offer PCIe 3.0 on Xeons later this year, and will start offering it on some mainstream cpus in 2012, so maybe Intel will launch TB v2 in 2013.