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Notes of Interest on Thunderbolt and MacBook Pro

mjteix said:
The technical brief also states that:

The Thunderbolt protocol physical layer is responsible for link maintenance including hot-plug detection, and data encoding to provide highly efficient data transfer.

A novel time synchronization protocol that allows all the Thunderbolt products connected in a domain to synchronize their time within 8ns of each other.

And by leveraging the inherently tight timing synchronization (within 8ns across 7 hops downstream from a host) and low latencies of Thunderbolt technology, broadcast-quality media can be produced using Thunderbolt products.
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That doesn' t mean developers have nothing to do, but I think that Intel has done its job. Just as with every technology, the implementation also needs to be done properly.
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First, hot-plug detection of the Thunderbolt connections does not imply proper hot-plug operation of the PCIe devices downstream - that's up to the 3rd party device drivers for those devices.

Second, having time synchronization of 8 nsec does not mean that you have latencies of 8 nsec.

In fact, it's bloody impossible to have latencies that low. Seven hops with 1m cables would have one-way latencies of at least 23 nsec - simply based on the speed of light. Look up "Grace Hopper nanosecond"....

You may be optimistic. I've developed and supported device drivers, so I have a more cautious view about what can happen when the bus latencies and timings change radically.

Couple that with the fact that very few 3rd party devices drivers have been developed for Apple OSX, and Margo Channing's famous misquote comes to mind:

"Fasten your seat belts, it's going to be a bumpy ride."
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After seeing just how small and fragile the Thunderbolt port looks,
I'm going on the side of caution.

Even if Apple says the port can be hot plugged, I'm not taking any chances.
The machine is getting shut down before I connect anything direct
into this critical port.

Just one accidental power spike or even a static discharge with so much
circuitry connected internally, I'm just not taking any chances on a $2400.00
machine.
 
that's one worry I wouldn't have

FFTT said:
Just one accidental power spike or even a static discharge with so much circuitry connected internally, I'm just not taking any chances on a $2400.00 machine.
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It's really not much of a change from the old mDP - which went straight to the GPU, chipset, or even the CPU package itself. Or an eSATA port that goes to the chipset, or Ethernet.

The engineering is pretty solid for protecting the chips from spikes - we've come a long ways from the days when plugging in a PS2 keyboard while the machine was running could fry the motherboard.
 
firestarter said:
Sounds like Intel was trying to integrate TB into USB, but the USB Implementers Forum were having none of it (as well they might - they see USB3 as the way forward).

The downside with working openly is slowness. How long would it have taken to bring TB to market if it had to go through an open review process.

As a partner Apple is ideal. They have the money, market volume and engineering skill to collaborate and help Intel put together a final product.
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My understanding is exactly that. They wanted to integrate it into USB which would have made things real easy, but the USB people simply would not allow it.

Seems like a weird response from A standards committee... I know they want to protect USB3, but their protectionism is short-sighted.
 
marksman said:
My understanding is exactly that. They wanted to integrate it into USB which would have made things real easy, but the USB people simply would not allow it.

Seems like a weird response from A standards committee... I know they want to protect USB3, but their protectionism is short-sighted.
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From where does this "understanding" come? Did Intel or Apple say that?

Putting the LightPeak optical leads on the "key" part of the USB connector did seem like a clever idea - although it would cause some fragmentation (confusion) about USB ports.

On the other hand, is it not possible that the real reason for the mDP connection is that when optical was abandoned, there wasn't any way to compatibly put enough additional wires in a USB port? (Four or eight conductors already, with all in use. Thunderbolt would seem to need six to ten conductors.)

Of course, on the Internet it's easier to spread a conspiracy theory than a rational explanation. ;)
 
USB sucks, I hate how you can't tell which way you are plugging it in. I imagine the optical connectors are more fragile too so you could run into problems when you mash it in the wrong way the 1000th time.
 
SilianRail said:
USB sucks, I hate how you can't tell which way you are plugging it in. I imagine the optical connectors are more fragile too so you could run into problems when you mash it in the wrong way the 1000th time.
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Let us know how well a mini-DisplayPort plug works after you "mash it in the wrong way the 1000th time". ;)

Seriously, though, look at your USB plug.

One side has a seam on the metal shield. That side is the bottom. (If you have a vertical USB port, you'll have to remember whether "left or right" is "top or bottom".)

You can also look for the USB glyph (the three tined fork) - that's on the top. I usually find that the seam on the metal shield is easier to find.
 
AidenShaw said:
First, hot-plug detection of the Thunderbolt connections does not imply proper hot-plug operation of the PCIe devices downstream - that's up to the 3rd party device drivers for those devices.

Second, having time synchronization of 8 nsec does not mean that you have latencies of 8 nsec.

In fact, it's bloody impossible to have latencies that low. Seven hops with 1m cables would have one-way latencies of at least 23 nsec - simply based on the speed of light. Look up "Grace Hopper nanosecond"....

You may be optimistic. I've developed and supported device drivers, so I have a more cautious view about what can happen when the bus latencies and timings change radically.

Couple that with the fact that very few 3rd party devices drivers have been developed for Apple OSX, and Margo Channing's famous misquote comes to mind:
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LOL, guess you have to be of a certain age to remember that film. One of the best.
 
AidenShaw said:
Let us know how well a mini-DisplayPort plug works after you "mash it in the wrong way the 1000th time". ;)

Seriously, though, look at your USB plug.

One side has a seam on the metal shield. That side is the bottom. (If you have a vertical USB port, you'll have to remember whether "left or right" is "top or bottom".)

You can also look for the USB glyph (the three tined fork) - that's on the top. I usually find that the seam on the metal shield is easier to find.
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Waaayyy too involved. :eek: You gotta make devices for the least common denominator. ;)
 
SilianRail said:
Waaayyy too involved. :eek: You gotta make devices for the least common denominator. ;)
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I hope that the LCD folks won't be buying Thunderbolt devices. The clueless meet the bleeding edge - recipe for disaster.

And, by the way, most of the LCD folks can figure out how to insert a USB cable/device. ;)
 
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jacksonkeller said:
LOL, guess you have to be of a certain age to remember that film. One of the best.
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Or, you need to be aware of and appreciate the classics of cinema - the films that have shaped what we see today.
____

Anyway, on topic, I have little doubt that by Apple OSX 10.7.2 and the "summer 2012" MacBook Pro systems that Thunderbolt will be quite solid, and there will only be a few circumstances where connecting or disconnecting a Thunderbolt device will cause a kernel panic.
 
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Bodypainter said:
whow, i am impressed. now i can copy a 4 GB file in 5 seconds, wherelse it used to take 50 seconds before. my life has now changed. i really need the new mac book, because i copy 4 GB files every day!
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Different people have different needs. Try pushing around a mere 50GB worth of dSLR photo/video over USB (or even FW) after most shoots (2x-4x that for a big shoot), and you'll quickly be looking for alternatives.


djrobsd said:
No add on cards for backwards compatibility? Wow, that's going to crush any existing system sales of Mac Pros, and other apple systems not yet updated to Thunderbolt... Not to mention the PC market as well... People will just wait now.
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This same factor (if really true) also puts pretty much an instant freeze on all Mac Pro sales in 2011...Thunderbolt (and obstruction? to upgrades to legacy hardware) have effectively EOL'ed all of Apple's unsold Mac Pro's. An upgrade can't come soon enough - - but the Xeon version of Sandy Bridge won't be out for probably another 6 months...a long, cold summer for Mac Pro retail sales is ahead...we'll watch & see if an Apple decision is made on the fate of the Mac Pro "truck" without acknowledging this (currently) poor timing that kills it.


-hh
 
AidenShaw said:
Anyway, on topic, I have little doubt that by Apple OSX 10.7.2 and the "summer 2012" MacBook Pro systems that Thunderbolt will be quite solid, and there will only be a few circumstances where connecting or disconnecting a Thunderbolt device will cause a kernel panic.
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Can you post links to documented incidents of TB disconnects causing kernel panics or are you making this stuff up?


-hh said:
Different people have different needs. Try pushing around a mere 50GB worth of dSLR photo/video over USB (or even FW) after most shoots (2x-4x that for a big shoot), and you'll quickly be looking for alternatives.
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Exactly. Maybe Bodypainter has never backed his system up. How long does it take to back up a 2TB drive to an external using USB?
 
But the Mac Pro already has PCIe slots....

-hh said:
This same factor (if really true) also puts pretty much an instant freeze on all Mac Pro sales in 2011...Thunderbolt (and obstruction? to upgrades to legacy hardware) have effectively EOL'ed all of Apple's unsold Mac Pro's.
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On the other hand, since the Mac Pro already has internal PCIe slots, it's less dependent on having daisy-chained external PCIe slots.

And, since there are exactly zero Thunderbolt devices on the market, it's not like there's any gizmo that you can use with a MacBook that you can't use with a Mac Pro.

However, if the third party vendors of audio/video professional tools abandon PCIe cards for Thunderbolt devices, a Mac Pro with several Thunderbolt ports can't come soon enough.

As far as storage, though, the Mac Pro is in fine shape today. A fibre channel card gives you high speed access to tons of TB of storage today.

It's also quite unlikely that within 6 months there will be a lot of Thunderbird devices on the market. If the "Sandy Xeon" Mac Pro has Thunderbird, it will probably show up at about the same time as the devices to use it.

I still have trouble understanding the Thunderbolt hype - it's an unseen, untested interface with zero products available. It looks interesting for the future, but today it is diddly squat. (http://en.wikipedia.org/wiki/Diddly_squat)


firestarter said:
Can you post links to documented incidents of TB disconnects causing kernel panics or are you making this stuff up?
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Can you post links to documented incidents of TB disconnects not causing kernel panics? ;)

No, because there are *no* Thunderbolt devices on the market.

One of my tenets of computer engineering is that "things which have not been tested do not work". Thunderbolt has not been tested in the real world with production devices. One should expect some "teething pains". Feel free to spend your money to alpha test Intel's new interface. I'll wait on the sidelines for now.
 
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AidenShaw said:
Can you post links to documented incidents of TB disconnects not causing kernel panics? ;)

No, because there are *no* Thunderbolt devices on the market.
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You're just making stuff up then. How dull.

One of my tenets of computer engineering is that "things which have not been tested do not work". Thunderbolt has not been tested in the real world with production devices. One should expect some "teething pains". Feel free to spend your money to alpha test Intel's new interface. I'll wait on the sidelines for now.
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Intel and Apple don't gross billions of dollars in sales by releasing untested gear. So if it's all the same, I think I'd trust their engineering teams over your 'tenet'.
 
firestarter said:
You're just making stuff up then. How dull.
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And you have faith, rather than facts.

Since there are no Thunderbolt products available today, neither you nor I can "make up" stories about success or failures with Thunderbolt. Put your money down, buy a new Apple, and enjoy the gamble that it will actually work.

Or go to Las Vegas, and throw your money away there.


firestarter said:
Intel and Apple don't gross billions of dollars in sales by releasing untested gear. So if it's all the same, I think I'd trust their engineering teams over your 'tenet'.
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Look up "Pentium floating point bug", or "chipsets for Sandy Bridge CPUs recalled for SATA bugs".

How could Apple possibly have tested Thunderbolt with off-the-shelf Thunderbolt products - since there are *no* Thunderbolt products on the shelves?

As I said, enjoy doing the alpha testing of Thunderbolt for Intel and Apple - I'll be watching from the sidelines.
 
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firestarter said:
Intel and Apple don't gross billions of dollars in sales by releasing untested gear. So if it's all the same, I think I'd trust their engineering teams over your 'tenet'.
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The risk of deploying something new is never zero.

Typically, the more revolutionary the change, the higher the risk ... and thus also, the level of investment to its preflight testing as risk mitigators.

As outsiders, we're never going to know what the assessed risks were, unless someone who was on the "inside" (and on an NDA) decides that they're free (legally or otherwise) to disclose the gory details to the public. At best, we can infer expectations based upon past performance.


-hh
 
AidenShaw said:
Oh. Wow.
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They probably did not want to run into DMI 2.0 bottlenecks. It reminds me of the PLX switching nonsense on P55 to accommodate dual GPUs along with USB 3.0 and SATA 6 Gbps. It would get bad an start eating into your GPU lanes. x8 bandwidth is more than enough for even the most powerful GPUs (Tom's Hardware and TechPowerUp! have done plenty of lane scaling investigations.) but I am sure we do not like to see it.
 
I can't imagine the plethora of TB accessories that some of you are predicting. It's going to be a while before a significant market exists for TB products, because as of right now, only the current line of MacBook Pros can even use them. That's a mighty small market to pour resources into building peripherals for. I don't see more than 2 or 3 coming out in the next year...I still think USB 3.0 would have been a better new port because peripherals already exist for them.
 
class77 said:
I still think USB 3.0 would have been a better new port because peripherals already exist for them.
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That was never going to happen because Intel doesn't support USB 3 with Sandy Bridge. So we need to deal with the situation we have and that is Thunderbolt. If you want USB 3, hopefully there'll be Thunderbolt adapters released to allow you to use it.
 
I was looking for Dell's U2711 before TB was announced.
Now I don't know if I should wait or not.
All info is quite fuzzy and most of all, no info on real products and no schedules about them.
If Dell would include TB hub in following model, I could wait for it.
If separate hub would be cheap enough, I could buy it.
If the hub would include usb3 & eSATA(p) it would be really useful.
If none of these happens, I could buy the display now.

I understand that Apple is against bd, but I can't get what they have against usb3.
Saving a dollar per computer?
Just trying to convince the audience that hardware specs don't matter, when state-of-the-art-for-the-rest-of-us is already so good without them?
Sad...

Will there be TB graphical cards or not?
Apple has teached as that single products and features does not mean anything, you need to think the whole ecosystem and in that perspective TB is still waporware.
 
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