4 ms·

This is some pretty exciting stuff. I read the wikis about the autopilot processing units and these ML accelerators and its honestly mind bogglingly exciting.

by idclip 7y ago

new_realist 7y ago
It’s slightly less powerful than NVIDIA’s self driving offering.
- dragontamer 7y ago
  "Powerful" is ambiguous in this context. There's TFlops (especially 8-bit vs 16-bit), there's memory bandwidth, there's cache locality, and there's simple benchmarks like ResNet-50. I haven't seen any real comparison between Nvidia and Tesla's neural processor. But I'd be interested in any comparison (even synthetic) to give an idea of the rough numbers. I'd expect these chips to be way slower than a desktop running a 500W GPU of course, but what numbers are we looking at exactly?
- gibolt 7y ago
  For the energy consumption per computation, it is supposedly ~10x better. That matters a lot when you have to account for a limited battery/range and cooling/extra hardware adding complexity to the car.
  - dragontamer 7y ago
    Personally speaking, I never liked this line of thinking. A Tesla has ~70 kW-hrs of energy, and its motor uses all of that power in 5-hours (5-hours x 60 miles per hour == 300 miles). Just round numbers for an estimate. For those paying attention, that's roughly 14,000 watts of power (again: round estimate, but we're probably +/- within a magnitude). Do you really care if your computer makes you use 14100 watts of power or 14500 watts of power?
    - steve_musk 7y ago
      Sure if you’re driving only on the highway. What about driving around the city at 5-20 mph? Tesla’s end goal is to have autopilot do everything, so if they are serious about it then it makes sense to consider the impact at non-highway speeds. Let’s say you are driving at an average speed of 20 mph - then by your estimate you’re using ~4666 watts. So if your chip is 500W it’s a significant portion of the power budget.
      - dragontamer 7y ago
        > What about driving around the city Autopilot is highway only for now. I'd expect the chip to be off, at least with the current version, if you are on city roads. But sure, if you're driving on city roads, lets really math it out. You have 70kW-hrs and maybe you're going 20 mph. Lets call that 4600 Watts of energy usage. Lets say you have a 500-Watt computer, for a total of 5100 Watts. You can run your car for literally 13-hours at that power-usage. 70 kW-hrs is a lot of energy storage. A 4600 Watt power-usage results in ~15 hours of runtime instead. Not a big change. And these are estimates only, I don't actually know what the energy-consumption metrics are for city vs highway. But these "poor calculations" are still good enough to realize that even a 500W computer is well within the power-budget of a 70,000 Watt-hr battery pack. ---------- Absolute worst case scenario (for the computer): you are going 0 MPH. Parked in a parking lot using only the computer. That means 100% of the power usage goes into the computer. What happens with a 500W computer? Well, 70 kW-hrs can last 140 hrs at 500Ws of usage, that's over a workweek: over 5 days of computer usage. Are we seriously worried about the miniscule power usage of the car's computer system when a 70 kW-hr battery is in the car?
        pests 7y ago
        Highway only? My roommate has one, I don't think he's ever not using autopilot even on side streets. He might only use the brake or accelerator a few times in a whole days driving.
        dragontamer 7y ago

This is some pretty exciting stuff. I read the wikis about the autopilot processing units and these ML accelerators and its honestly mind bogglingly exciting.

by idclip 7y ago

This is some pretty exciting stuff. I read the wikis about the autopilot processing units and these ML accelerators and its honestly mind bogglingly exciting.

new_realist 7y ago

It’s slightly less powerful than NVIDIA’s self driving offering.

dragontamer 7y ago
"Powerful" is ambiguous in this context. There's TFlops (especially 8-bit vs 16-bit), there's memory bandwidth, there's cache locality, and there's simple benchmarks like ResNet-50. I haven't seen any real comparison between Nvidia and Tesla's neural processor. But I'd be interested in any comparison (even synthetic) to give an idea of the rough numbers. I'd expect these chips to be way slower than a desktop running a 500W GPU of course, but what numbers are we looking at exactly?
gibolt 7y ago
For the energy consumption per computation, it is supposedly ~10x better. That matters a lot when you have to account for a limited battery/range and cooling/extra hardware adding complexity to the car.
- dragontamer 7y ago
  Personally speaking, I never liked this line of thinking. A Tesla has ~70 kW-hrs of energy, and its motor uses all of that power in 5-hours (5-hours x 60 miles per hour == 300 miles). Just round numbers for an estimate. For those paying attention, that's roughly 14,000 watts of power (again: round estimate, but we're probably +/- within a magnitude). Do you really care if your computer makes you use 14100 watts of power or 14500 watts of power?
  - steve_musk 7y ago
    Sure if you’re driving only on the highway. What about driving around the city at 5-20 mph? Tesla’s end goal is to have autopilot do everything, so if they are serious about it then it makes sense to consider the impact at non-highway speeds. Let’s say you are driving at an average speed of 20 mph - then by your estimate you’re using ~4666 watts. So if your chip is 500W it’s a significant portion of the power budget.
    - dragontamer 7y ago
      > What about driving around the city Autopilot is highway only for now. I'd expect the chip to be off, at least with the current version, if you are on city roads. But sure, if you're driving on city roads, lets really math it out. You have 70kW-hrs and maybe you're going 20 mph. Lets call that 4600 Watts of energy usage. Lets say you have a 500-Watt computer, for a total of 5100 Watts. You can run your car for literally 13-hours at that power-usage. 70 kW-hrs is a lot of energy storage. A 4600 Watt power-usage results in ~15 hours of runtime instead. Not a big change. And these are estimates only, I don't actually know what the energy-consumption metrics are for city vs highway. But these "poor calculations" are still good enough to realize that even a 500W computer is well within the power-budget of a 70,000 Watt-hr battery pack. ---------- Absolute worst case scenario (for the computer): you are going 0 MPH. Parked in a parking lot using only the computer. That means 100% of the power usage goes into the computer. What happens with a 500W computer? Well, 70 kW-hrs can last 140 hrs at 500Ws of usage, that's over a workweek: over 5 days of computer usage. Are we seriously worried about the miniscule power usage of the car's computer system when a 70 kW-hr battery is in the car?
      - pests 7y ago
        Highway only? My roommate has one, I don't think he's ever not using autopilot even on side streets. He might only use the brake or accelerator a few times in a whole days driving.
        dragontamer 7y ago